Work again on bug 269966.

I think this time we do have a robust fix.  I added tests that do fail after
John Hunter's example, so if this one ever tries to return, we should catch
it right away.

Very, very nasty bug...

IPython/tests/refbug.py

@@ -0,0 +1,38 b''
+"""Minimal script to reproduce our nasty reference counting bug.
+
+The problem is related to https://bugs.launchpad.net/ipython/+bug/269966
+
+The original fix for that appeared to work, but JD Hunter found a matplotlib
+example which, when run twice in a row, would break.  The problem were
+references held by open figures to internals of Tkinter.
+
+This code reproduces the problem that John saw, without matplotlib.  We can
+thus use it for our test suite.
+"""
+
+#-----------------------------------------------------------------------------
+# Module imports
+#-----------------------------------------------------------------------------
+import sys
+
+from IPython import ipapi
+
+#-----------------------------------------------------------------------------
+# Globals
+#-----------------------------------------------------------------------------
+ip = ipapi.get()
+
+if not '_refbug_cache' in ip.user_ns:
+    ip.user_ns['_refbug_cache'] = []
+
+
+aglobal = 'Hello'
+def f():
+    return aglobal
+
+cache = ip.user_ns['_refbug_cache']
+cache.append(f)
+
+def call_f():
+    for func in cache:
+        print 'lowercased:',func().lower()

IPython/tests/test_fakemodule.py

@@ -0,0 +1,17 b''
+"""Tests for the FakeModule objects.
+"""
+
+import nose.tools as nt
+
+from IPython.FakeModule import FakeModule, init_fakemod_dict
+
+# Make a fakemod and check a few properties
+def test_mk_fakemod():
+    fm = FakeModule()
+    yield nt.assert_true,fm
+    yield nt.assert_true,lambda : hasattr(fm,'__file__')
+
+def test_mk_fakemod_fromdict():
+    """Test making a FakeModule object with initial data"""
+    fm = FakeModule(dict(hello=True))
+    nt.assert_true(fm.hello)

IPython/FakeModule.py

@@ -1,42 +1,66 b''
 # -*- coding: utf-8 -*-
 """
 Class which mimics a module.
 
 Needed to allow pickle to correctly resolve namespaces during IPython
 sessions.
 """
 
 #*****************************************************************************
 #       Copyright (C) 2002-2004 Fernando Perez. <[e-mail]>
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #*****************************************************************************
 
 import types
 
+def init_fakemod_dict(fm,adict=None):
+    """Initialize a FakeModule instance __dict__.
+
+    Kept as a standalone function and not a method so the FakeModule API can
+    remain basically empty.
+
+    This should be considered for private IPython use, used in managing
+    namespaces for %run.
+
+    Parameters
+    ----------
+
+    fm : FakeModule instance
+
+    adict : dict, optional
+    """
+
+    dct = {}
+    # It seems pydoc (and perhaps others) needs any module instance to
+    # implement a __nonzero__ method, so we add it if missing:
+    dct.setdefault('__nonzero__',lambda : True)
+    dct.setdefault('__file__',__file__)
+
+    if adict is not None:
+        dct.update(adict)
+
+    # Hard assignment of the object's __dict__.  This is nasty but deliberate.
+    fm.__dict__.clear()
+    fm.__dict__.update(dct)
+
+
 class FakeModule(types.ModuleType):
     """Simple class with attribute access to fake a module.
 
     This is not meant to replace a module, but to allow inserting a fake
     module in sys.modules so that systems which rely on run-time module
     importing (like shelve and pickle) work correctly in interactive IPython
     sessions.
 
     Do NOT use this code for anything other than this IPython private hack."""
 
     def __init__(self,adict=None):
         
         # tmp to force __dict__ instance creation, else self.__dict__ fails
         self.__iptmp = None
-        
-        # It seems pydoc (and perhaps others) needs any module instance to
-        # implement a __nonzero__ method, so we add it if missing:
-        self.__dict__.setdefault('__nonzero__',lambda : True)
-        self.__dict__.setdefault('__file__',__file__)
-
         # cleanup our temp trick
         del self.__iptmp
-
-        if adict is not None:
-            self.__dict__.update(adict)
+        # Now, initialize the actual data in the instance dict.
+        init_fakemod_dict(self,adict)

IPython/Magic.py

@@ -1,3442 +1,3447 b''
 # -*- coding: utf-8 -*-
 """Magic functions for InteractiveShell.
 """
 
 #*****************************************************************************
 #       Copyright (C) 2001 Janko Hauser <[e-mail]> and
 #       Copyright (C) 2001-2006 Fernando Perez <[e-mail]>
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #*****************************************************************************
 
 #****************************************************************************
 # Modules and globals
 
 # Python standard modules
 import __builtin__
 import bdb
 import inspect
 import os
 import pdb
 import pydoc
 import sys
 import re
 import tempfile
 import time
 import cPickle as pickle
 import textwrap
 from cStringIO import StringIO
 from getopt import getopt,GetoptError
 from pprint import pprint, pformat
 
 # cProfile was added in Python2.5
 try:
     import cProfile as profile
     import pstats
 except ImportError:
     # profile isn't bundled by default in Debian for license reasons
     try:
         import profile,pstats
     except ImportError:
         profile = pstats = None
 
 # Homebrewed
 import IPython
 from IPython import Debugger, OInspect, wildcard
 from IPython.FakeModule import FakeModule
 from IPython.Itpl import Itpl, itpl, printpl,itplns
 from IPython.PyColorize import Parser
 from IPython.ipstruct import Struct
 from IPython.macro import Macro
 from IPython.genutils import *
 from IPython import platutils
 import IPython.generics
 import IPython.ipapi
 from IPython.ipapi import UsageError
 from IPython.testing import decorators as testdec
 
 #***************************************************************************
 # Utility functions
 def on_off(tag):
     """Return an ON/OFF string for a 1/0 input. Simple utility function."""
     return ['OFF','ON'][tag]
 
 class Bunch: pass
 
 def compress_dhist(dh):
     head, tail = dh[:-10], dh[-10:]
 
     newhead = []
     done = set()
     for h in head:
         if h in done:
             continue
         newhead.append(h)
         done.add(h)
 
     return newhead + tail        
         
 
 #***************************************************************************
 # Main class implementing Magic functionality
 class Magic:
     """Magic functions for InteractiveShell.
 
     Shell functions which can be reached as %function_name. All magic
     functions should accept a string, which they can parse for their own
     needs. This can make some functions easier to type, eg `%cd ../`
     vs. `%cd("../")`
 
     ALL definitions MUST begin with the prefix magic_. The user won't need it
     at the command line, but it is is needed in the definition. """
 
     # class globals
     auto_status = ['Automagic is OFF, % prefix IS needed for magic functions.',
                    'Automagic is ON, % prefix NOT needed for magic functions.']
 
     #......................................................................
     # some utility functions
 
     def __init__(self,shell):
         
         self.options_table = {}
         if profile is None:
             self.magic_prun = self.profile_missing_notice
         self.shell = shell
 
         # namespace for holding state we may need
         self._magic_state = Bunch()
 
     def profile_missing_notice(self, *args, **kwargs):
         error("""\
 The profile module could not be found. It has been removed from the standard
 python packages because of its non-free license. To use profiling, install the
 python-profiler package from non-free.""")
 
     def default_option(self,fn,optstr):
         """Make an entry in the options_table for fn, with value optstr"""
 
         if fn not in self.lsmagic():
             error("%s is not a magic function" % fn)
         self.options_table[fn] = optstr
 
     def lsmagic(self):
         """Return a list of currently available magic functions.
 
         Gives a list of the bare names after mangling (['ls','cd', ...], not
         ['magic_ls','magic_cd',...]"""
 
         # FIXME. This needs a cleanup, in the way the magics list is built.
         
         # magics in class definition
         class_magic = lambda fn: fn.startswith('magic_') and \
                       callable(Magic.__dict__[fn])
         # in instance namespace (run-time user additions)
         inst_magic =  lambda fn: fn.startswith('magic_') and \
                      callable(self.__dict__[fn])
         # and bound magics by user (so they can access self):
         inst_bound_magic =  lambda fn: fn.startswith('magic_') and \
                            callable(self.__class__.__dict__[fn])
         magics = filter(class_magic,Magic.__dict__.keys()) + \
                  filter(inst_magic,self.__dict__.keys()) + \
                  filter(inst_bound_magic,self.__class__.__dict__.keys())
         out = []
         for fn in set(magics):
             out.append(fn.replace('magic_','',1))
         out.sort()
         return out
     
     def extract_input_slices(self,slices,raw=False):
         """Return as a string a set of input history slices.
 
         Inputs:
 
           - slices: the set of slices is given as a list of strings (like
           ['1','4:8','9'], since this function is for use by magic functions
           which get their arguments as strings.
 
         Optional inputs:
 
           - raw(False): by default, the processed input is used.  If this is
           true, the raw input history is used instead.
 
         Note that slices can be called with two notations:
 
         N:M -> standard python form, means including items N...(M-1).
 
         N-M -> include items N..M (closed endpoint)."""
 
         if raw:
             hist = self.shell.input_hist_raw
         else:
             hist = self.shell.input_hist
 
         cmds = []
         for chunk in slices:
             if ':' in chunk:
                 ini,fin = map(int,chunk.split(':'))
             elif '-' in chunk:
                 ini,fin = map(int,chunk.split('-'))
                 fin += 1
             else:
                 ini = int(chunk)
                 fin = ini+1
             cmds.append(hist[ini:fin])
         return cmds
         
     def _ofind(self, oname, namespaces=None):
         """Find an object in the available namespaces.
 
         self._ofind(oname) -> dict with keys: found,obj,ospace,ismagic
 
         Has special code to detect magic functions.
         """
         
         oname = oname.strip()
 
         alias_ns = None
         if namespaces is None:
             # Namespaces to search in:
             # Put them in a list. The order is important so that we
             # find things in the same order that Python finds them.
             namespaces = [ ('Interactive', self.shell.user_ns),
                            ('IPython internal', self.shell.internal_ns),
                            ('Python builtin', __builtin__.__dict__),
                            ('Alias', self.shell.alias_table),
                            ]
             alias_ns = self.shell.alias_table
 
         # initialize results to 'null'
         found = 0; obj = None;  ospace = None;  ds = None;
         ismagic = 0; isalias = 0; parent = None
 
         # Look for the given name by splitting it in parts.  If the head is
         # found, then we look for all the remaining parts as members, and only
         # declare success if we can find them all.
         oname_parts = oname.split('.')
         oname_head, oname_rest = oname_parts[0],oname_parts[1:]
         for nsname,ns in namespaces:
             try:
                 obj = ns[oname_head]
             except KeyError:
                 continue
             else:
                 #print 'oname_rest:', oname_rest  # dbg
                 for part in oname_rest:
                     try:
                         parent = obj
                         obj = getattr(obj,part)
                     except:
                         # Blanket except b/c some badly implemented objects
                         # allow __getattr__ to raise exceptions other than
                         # AttributeError, which then crashes IPython.
                         break
                 else:
                     # If we finish the for loop (no break), we got all members
                     found = 1
                     ospace = nsname
                     if ns == alias_ns:
                         isalias = 1
                     break  # namespace loop
 
         # Try to see if it's magic
         if not found:
             if oname.startswith(self.shell.ESC_MAGIC):
                 oname = oname[1:]
             obj = getattr(self,'magic_'+oname,None)
             if obj is not None:
                 found = 1
                 ospace = 'IPython internal'
                 ismagic = 1
 
         # Last try: special-case some literals like '', [], {}, etc:
         if not found and oname_head in ["''",'""','[]','{}','()']:
             obj = eval(oname_head)
             found = 1
             ospace = 'Interactive'
             
         return {'found':found, 'obj':obj, 'namespace':ospace,
                 'ismagic':ismagic, 'isalias':isalias, 'parent':parent}
     
     def arg_err(self,func):
         """Print docstring if incorrect arguments were passed"""
         print 'Error in arguments:'
         print OInspect.getdoc(func)
 
     def format_latex(self,strng):
         """Format a string for latex inclusion."""
 
         # Characters that need to be escaped for latex:
         escape_re = re.compile(r'(%|_|\$|#|&)',re.MULTILINE)
         # Magic command names as headers:
         cmd_name_re = re.compile(r'^(%s.*?):' % self.shell.ESC_MAGIC,
                                  re.MULTILINE)
         # Magic commands 
         cmd_re = re.compile(r'(?P<cmd>%s.+?\b)(?!\}\}:)' % self.shell.ESC_MAGIC,
                             re.MULTILINE)
         # Paragraph continue
         par_re = re.compile(r'\\$',re.MULTILINE)
 
         # The "\n" symbol
         newline_re = re.compile(r'\\n')
 
         # Now build the string for output:
         #strng = cmd_name_re.sub(r'\n\\texttt{\\textsl{\\large \1}}:',strng)
         strng = cmd_name_re.sub(r'\n\\bigskip\n\\texttt{\\textbf{ \1}}:',
                                 strng)
         strng = cmd_re.sub(r'\\texttt{\g<cmd>}',strng)
         strng = par_re.sub(r'\\\\',strng)
         strng = escape_re.sub(r'\\\1',strng)
         strng = newline_re.sub(r'\\textbackslash{}n',strng)
         return strng
 
     def format_screen(self,strng):
         """Format a string for screen printing.
 
         This removes some latex-type format codes."""
         # Paragraph continue
         par_re = re.compile(r'\\$',re.MULTILINE)
         strng = par_re.sub('',strng)
         return strng
 
     def parse_options(self,arg_str,opt_str,*long_opts,**kw):
         """Parse options passed to an argument string.
 
         The interface is similar to that of getopt(), but it returns back a
         Struct with the options as keys and the stripped argument string still
         as a string.
 
         arg_str is quoted as a true sys.argv vector by using shlex.split.
         This allows us to easily expand variables, glob files, quote
         arguments, etc.
 
         Options:
           -mode: default 'string'. If given as 'list', the argument string is
           returned as a list (split on whitespace) instead of a string.
 
           -list_all: put all option values in lists. Normally only options
           appearing more than once are put in a list.
 
           -posix (True): whether to split the input line in POSIX mode or not,
           as per the conventions outlined in the shlex module from the
           standard library."""
  
         # inject default options at the beginning of the input line
         caller = sys._getframe(1).f_code.co_name.replace('magic_','')
         arg_str = '%s %s' % (self.options_table.get(caller,''),arg_str)
         
         mode = kw.get('mode','string')
         if mode not in ['string','list']:
             raise ValueError,'incorrect mode given: %s' % mode
         # Get options
         list_all = kw.get('list_all',0)
         posix = kw.get('posix',True)
 
         # Check if we have more than one argument to warrant extra processing:
         odict = {}  # Dictionary with options
         args = arg_str.split()
         if len(args) >= 1:
             # If the list of inputs only has 0 or 1 thing in it, there's no
             # need to look for options
             argv = arg_split(arg_str,posix)
             # Do regular option processing
             try:
                 opts,args = getopt(argv,opt_str,*long_opts)
             except GetoptError,e:
                 raise UsageError('%s ( allowed: "%s" %s)' % (e.msg,opt_str, 
                                         " ".join(long_opts)))
             for o,a in opts:
                 if o.startswith('--'):
                     o = o[2:]
                 else:
                     o = o[1:]
                 try:
                     odict[o].append(a)
                 except AttributeError:
                     odict[o] = [odict[o],a]
                 except KeyError:
                     if list_all:
                         odict[o] = [a]
                     else:
                         odict[o] = a
 
         # Prepare opts,args for return
         opts = Struct(odict)
         if mode == 'string':
             args = ' '.join(args)
 
         return opts,args
     
     #......................................................................
     # And now the actual magic functions
 
     # Functions for IPython shell work (vars,funcs, config, etc)
     def magic_lsmagic(self, parameter_s = ''):
         """List currently available magic functions."""
         mesc = self.shell.ESC_MAGIC
         print 'Available magic functions:\n'+mesc+\
               ('  '+mesc).join(self.lsmagic())
         print '\n' + Magic.auto_status[self.shell.rc.automagic]
         return None
         
     def magic_magic(self, parameter_s = ''):
         """Print information about the magic function system.
         
         Supported formats: -latex, -brief, -rest        
         """
 
         mode = ''
         try:
             if parameter_s.split()[0] == '-latex':
                 mode = 'latex'
             if parameter_s.split()[0] == '-brief':
                 mode = 'brief'
             if parameter_s.split()[0] == '-rest':
                 mode = 'rest'
                 rest_docs = []
         except:
             pass
 
         magic_docs = []
         for fname in self.lsmagic():
             mname = 'magic_' + fname
             for space in (Magic,self,self.__class__):
                 try:
                     fn = space.__dict__[mname]
                 except KeyError:
                     pass
                 else:
                     break
             if mode == 'brief':
                 # only first line
                 if fn.__doc__:                    
                     fndoc = fn.__doc__.split('\n',1)[0]
                 else:
                     fndoc = 'No documentation'
             else:
                 if fn.__doc__:
                     fndoc = fn.__doc__.rstrip()       
                 else:
                     fndoc = 'No documentation'
                 
                 
             if mode == 'rest':
                 rest_docs.append('**%s%s**::\n\n\t%s\n\n' %(self.shell.ESC_MAGIC,
                                                     fname,fndoc))
                 
             else:
                 magic_docs.append('%s%s:\n\t%s\n' %(self.shell.ESC_MAGIC,
                                                     fname,fndoc))
                 
         magic_docs = ''.join(magic_docs)
 
         if mode == 'rest':
             return "".join(rest_docs)
         
         if mode == 'latex':
             print self.format_latex(magic_docs)
             return
         else:
             magic_docs = self.format_screen(magic_docs)
         if mode == 'brief':
             return magic_docs
         
         outmsg = """
 IPython's 'magic' functions
 ===========================
 
 The magic function system provides a series of functions which allow you to
 control the behavior of IPython itself, plus a lot of system-type
 features. All these functions are prefixed with a % character, but parameters
 are given without parentheses or quotes.
 
 NOTE: If you have 'automagic' enabled (via the command line option or with the
 %automagic function), you don't need to type in the % explicitly.  By default,
 IPython ships with automagic on, so you should only rarely need the % escape.
 
 Example: typing '%cd mydir' (without the quotes) changes you working directory
 to 'mydir', if it exists.
 
 You can define your own magic functions to extend the system. See the supplied
 ipythonrc and example-magic.py files for details (in your ipython
 configuration directory, typically $HOME/.ipython/).
 
 You can also define your own aliased names for magic functions. In your
 ipythonrc file, placing a line like:
 
   execute __IPYTHON__.magic_pf = __IPYTHON__.magic_profile
 
 will define %pf as a new name for %profile.
 
 You can also call magics in code using the ipmagic() function, which IPython
 automatically adds to the builtin namespace.  Type 'ipmagic?' for details.
 
 For a list of the available magic functions, use %lsmagic. For a description
 of any of them, type %magic_name?, e.g. '%cd?'.
 
 Currently the magic system has the following functions:\n"""
 
         mesc = self.shell.ESC_MAGIC
         outmsg = ("%s\n%s\n\nSummary of magic functions (from %slsmagic):"
                   "\n\n%s%s\n\n%s" % (outmsg,
                                      magic_docs,mesc,mesc,
                                      ('  '+mesc).join(self.lsmagic()),
                                      Magic.auto_status[self.shell.rc.automagic] ) )
 
         page(outmsg,screen_lines=self.shell.rc.screen_length)
   
 
     def magic_autoindent(self, parameter_s = ''):
         """Toggle autoindent on/off (if available)."""
 
         self.shell.set_autoindent()
         print "Automatic indentation is:",['OFF','ON'][self.shell.autoindent]
 
 
     def magic_automagic(self, parameter_s = ''):
         """Make magic functions callable without having to type the initial %.
 
         Without argumentsl toggles on/off (when off, you must call it as
         %automagic, of course).  With arguments it sets the value, and you can
         use any of (case insensitive):
 
          - on,1,True: to activate
 
          - off,0,False: to deactivate.
 
         Note that magic functions have lowest priority, so if there's a
         variable whose name collides with that of a magic fn, automagic won't
         work for that function (you get the variable instead). However, if you
         delete the variable (del var), the previously shadowed magic function
         becomes visible to automagic again."""
 
         rc = self.shell.rc
         arg = parameter_s.lower()
         if parameter_s in ('on','1','true'):
             rc.automagic = True
         elif parameter_s in ('off','0','false'):
             rc.automagic = False
         else:
             rc.automagic = not rc.automagic
         print '\n' + Magic.auto_status[rc.automagic]
 
     @testdec.skip_doctest
     def magic_autocall(self, parameter_s = ''):
         """Make functions callable without having to type parentheses.
 
         Usage:
 
            %autocall [mode]
 
         The mode can be one of: 0->Off, 1->Smart, 2->Full.  If not given, the
         value is toggled on and off (remembering the previous state).
 
         In more detail, these values mean:
 
         0 -> fully disabled
 
         1 -> active, but do not apply if there are no arguments on the line.
 
         In this mode, you get:
 
         In [1]: callable
         Out[1]: <built-in function callable>
 
         In [2]: callable 'hello'
         ------> callable('hello')
         Out[2]: False
 
         2 -> Active always.  Even if no arguments are present, the callable
         object is called:
 
         In [2]: float
         ------> float()
         Out[2]: 0.0
 
         Note that even with autocall off, you can still use '/' at the start of
         a line to treat the first argument on the command line as a function
         and add parentheses to it:
 
         In [8]: /str 43
         ------> str(43)
         Out[8]: '43'
 
         # all-random (note for auto-testing)
         """
 
         rc = self.shell.rc
 
         if parameter_s:
             arg = int(parameter_s)
         else:
             arg = 'toggle'
 
         if not arg in (0,1,2,'toggle'):
             error('Valid modes: (0->Off, 1->Smart, 2->Full')
             return
 
         if arg in (0,1,2):
             rc.autocall = arg
         else: # toggle
             if rc.autocall:
                 self._magic_state.autocall_save = rc.autocall
                 rc.autocall = 0
             else:
                 try:
                     rc.autocall = self._magic_state.autocall_save
                 except AttributeError:
                     rc.autocall = self._magic_state.autocall_save = 1
 
         print "Automatic calling is:",['OFF','Smart','Full'][rc.autocall]
 
     def magic_system_verbose(self, parameter_s = ''):
         """Set verbose printing of system calls.
 
         If called without an argument, act as a toggle"""
 
         if parameter_s:
             val = bool(eval(parameter_s))
         else:
             val = None
             
         self.shell.rc_set_toggle('system_verbose',val)
         print "System verbose printing is:",\
               ['OFF','ON'][self.shell.rc.system_verbose]
 
 
     def magic_page(self, parameter_s=''):
         """Pretty print the object and display it through a pager.
         
         %page [options] OBJECT
 
         If no object is given, use _ (last output).
         
         Options:
 
           -r: page str(object), don't pretty-print it."""
 
         # After a function contributed by Olivier Aubert, slightly modified.
 
         # Process options/args
         opts,args = self.parse_options(parameter_s,'r')
         raw = 'r' in opts
 
         oname = args and args or '_'
         info = self._ofind(oname)
         if info['found']:
             txt = (raw and str or pformat)( info['obj'] )
             page(txt)
         else:
             print 'Object `%s` not found' % oname
 
     def magic_profile(self, parameter_s=''):
         """Print your currently active IPyhton profile."""
         if self.shell.rc.profile:
             printpl('Current IPython profile: $self.shell.rc.profile.')
         else:
             print 'No profile active.'
 
     def magic_pinfo(self, parameter_s='', namespaces=None):
         """Provide detailed information about an object.
     
         '%pinfo object' is just a synonym for object? or ?object."""
     
         #print 'pinfo par: <%s>' % parameter_s  # dbg
     
         
         # detail_level: 0 -> obj? , 1 -> obj??
         detail_level = 0
         # We need to detect if we got called as 'pinfo pinfo foo', which can
         # happen if the user types 'pinfo foo?' at the cmd line.
         pinfo,qmark1,oname,qmark2 = \
                re.match('(pinfo )?(\?*)(.*?)(\??$)',parameter_s).groups()
         if pinfo or qmark1 or qmark2:
             detail_level = 1
         if "*" in oname:
             self.magic_psearch(oname)
         else:
             self._inspect('pinfo', oname, detail_level=detail_level,
                           namespaces=namespaces)
 
     def magic_pdef(self, parameter_s='', namespaces=None):
         """Print the definition header for any callable object.
 
         If the object is a class, print the constructor information."""
         self._inspect('pdef',parameter_s, namespaces)
 
     def magic_pdoc(self, parameter_s='', namespaces=None):
         """Print the docstring for an object.
 
         If the given object is a class, it will print both the class and the
         constructor docstrings."""
         self._inspect('pdoc',parameter_s, namespaces)
 
     def magic_psource(self, parameter_s='', namespaces=None):
         """Print (or run through pager) the source code for an object."""
         self._inspect('psource',parameter_s, namespaces)
 
     def magic_pfile(self, parameter_s=''):
         """Print (or run through pager) the file where an object is defined.
 
         The file opens at the line where the object definition begins. IPython
         will honor the environment variable PAGER if set, and otherwise will
         do its best to print the file in a convenient form.
 
         If the given argument is not an object currently defined, IPython will
         try to interpret it as a filename (automatically adding a .py extension
         if needed). You can thus use %pfile as a syntax highlighting code
         viewer."""
 
         # first interpret argument as an object name
         out = self._inspect('pfile',parameter_s)
         # if not, try the input as a filename
         if out == 'not found':
             try:
                 filename = get_py_filename(parameter_s)
             except IOError,msg:
                 print msg
                 return
             page(self.shell.inspector.format(file(filename).read()))
 
     def _inspect(self,meth,oname,namespaces=None,**kw):
         """Generic interface to the inspector system.
 
         This function is meant to be called by pdef, pdoc & friends."""
 
         #oname = oname.strip()
         #print '1- oname: <%r>' % oname  # dbg
         try:
             oname = oname.strip().encode('ascii')
             #print '2- oname: <%r>' % oname  # dbg
         except UnicodeEncodeError:
             print 'Python identifiers can only contain ascii characters.'
             return 'not found'
             
         info = Struct(self._ofind(oname, namespaces))
         
         if info.found:
             try:
                 IPython.generics.inspect_object(info.obj)
                 return
             except IPython.ipapi.TryNext:
                 pass
             # Get the docstring of the class property if it exists.
             path = oname.split('.')
             root = '.'.join(path[:-1])
             if info.parent is not None:
                 try:
                     target = getattr(info.parent, '__class__') 
                     # The object belongs to a class instance. 
                     try: 
                         target = getattr(target, path[-1])
                         # The class defines the object. 
                         if isinstance(target, property):
                             oname = root + '.__class__.' + path[-1]
                             info = Struct(self._ofind(oname))
                     except AttributeError: pass
                 except AttributeError: pass
                         
             pmethod = getattr(self.shell.inspector,meth)
             formatter = info.ismagic and self.format_screen or None
             if meth == 'pdoc':
                 pmethod(info.obj,oname,formatter)
             elif meth == 'pinfo':
                 pmethod(info.obj,oname,formatter,info,**kw)
             else:
                 pmethod(info.obj,oname)
         else:
             print 'Object `%s` not found.' % oname
             return 'not found'  # so callers can take other action
         
     def magic_psearch(self, parameter_s=''):
         """Search for object in namespaces by wildcard.
 
         %psearch [options] PATTERN [OBJECT TYPE]
 
         Note: ? can be used as a synonym for %psearch, at the beginning or at
         the end: both a*? and ?a* are equivalent to '%psearch a*'.  Still, the
         rest of the command line must be unchanged (options come first), so
         for example the following forms are equivalent
 
         %psearch -i a* function
         -i a* function?
         ?-i a* function
 
         Arguments:
         
           PATTERN
 
           where PATTERN is a string containing * as a wildcard similar to its
           use in a shell.  The pattern is matched in all namespaces on the
           search path. By default objects starting with a single _ are not
           matched, many IPython generated objects have a single
           underscore. The default is case insensitive matching. Matching is
           also done on the attributes of objects and not only on the objects
           in a module.
 
           [OBJECT TYPE]
 
           Is the name of a python type from the types module. The name is
           given in lowercase without the ending type, ex. StringType is
           written string. By adding a type here only objects matching the
           given type are matched. Using all here makes the pattern match all
           types (this is the default).
 
         Options:
 
           -a: makes the pattern match even objects whose names start with a
           single underscore.  These names are normally ommitted from the
           search.
 
           -i/-c: make the pattern case insensitive/sensitive.  If neither of
           these options is given, the default is read from your ipythonrc
           file.  The option name which sets this value is
           'wildcards_case_sensitive'.  If this option is not specified in your
           ipythonrc file, IPython's internal default is to do a case sensitive
           search.
 
           -e/-s NAMESPACE: exclude/search a given namespace.  The pattern you
           specifiy can be searched in any of the following namespaces:
           'builtin', 'user', 'user_global','internal', 'alias', where
           'builtin' and 'user' are the search defaults.  Note that you should
           not use quotes when specifying namespaces.
 
           'Builtin' contains the python module builtin, 'user' contains all
           user data, 'alias' only contain the shell aliases and no python
           objects, 'internal' contains objects used by IPython.  The
           'user_global' namespace is only used by embedded IPython instances,
           and it contains module-level globals.  You can add namespaces to the
           search with -s or exclude them with -e (these options can be given
           more than once).
     
         Examples:
        
         %psearch a*            -> objects beginning with an a
         %psearch -e builtin a* -> objects NOT in the builtin space starting in a
         %psearch a* function   -> all functions beginning with an a
         %psearch re.e*         -> objects beginning with an e in module re
         %psearch r*.e*         -> objects that start with e in modules starting in r
         %psearch r*.* string   -> all strings in modules beginning with r
 
         Case sensitve search:
        
         %psearch -c a*         list all object beginning with lower case a
 
         Show objects beginning with a single _:
        
         %psearch -a _*         list objects beginning with a single underscore"""
         try:
             parameter_s = parameter_s.encode('ascii')
         except UnicodeEncodeError:
             print 'Python identifiers can only contain ascii characters.'
             return
 
         # default namespaces to be searched
         def_search = ['user','builtin']
 
         # Process options/args
         opts,args = self.parse_options(parameter_s,'cias:e:',list_all=True)
         opt = opts.get
         shell = self.shell
         psearch = shell.inspector.psearch
 
         # select case options
         if opts.has_key('i'):
             ignore_case = True
         elif opts.has_key('c'):
             ignore_case = False
         else:
             ignore_case = not shell.rc.wildcards_case_sensitive
 
         # Build list of namespaces to search from user options
         def_search.extend(opt('s',[]))
         ns_exclude = ns_exclude=opt('e',[])
         ns_search = [nm for nm in def_search if nm not in ns_exclude]
         
         # Call the actual search
         try:
             psearch(args,shell.ns_table,ns_search,
                     show_all=opt('a'),ignore_case=ignore_case)
         except:
             shell.showtraceback()
 
     def magic_who_ls(self, parameter_s=''):
         """Return a sorted list of all interactive variables.
 
         If arguments are given, only variables of types matching these
         arguments are returned."""
 
         user_ns = self.shell.user_ns
         internal_ns = self.shell.internal_ns
         user_config_ns = self.shell.user_config_ns
         out = []
         typelist = parameter_s.split()
 
         for i in user_ns:
             if not (i.startswith('_') or i.startswith('_i')) \
                    and not (i in internal_ns or i in user_config_ns):
                 if typelist:
                     if type(user_ns[i]).__name__ in typelist:
                         out.append(i)
                 else:
                     out.append(i)
         out.sort()
         return out
         
     def magic_who(self, parameter_s=''):
         """Print all interactive variables, with some minimal formatting.
 
         If any arguments are given, only variables whose type matches one of
         these are printed.  For example:
 
           %who function str
 
         will only list functions and strings, excluding all other types of
         variables.  To find the proper type names, simply use type(var) at a
         command line to see how python prints type names.  For example:
 
           In [1]: type('hello')\\
           Out[1]: <type 'str'>
 
         indicates that the type name for strings is 'str'.
 
         %who always excludes executed names loaded through your configuration
         file and things which are internal to IPython.
 
         This is deliberate, as typically you may load many modules and the
         purpose of %who is to show you only what you've manually defined."""
 
         varlist = self.magic_who_ls(parameter_s)
         if not varlist:
             if parameter_s:
                 print 'No variables match your requested type.'
             else:
                 print 'Interactive namespace is empty.'
             return
 
         # if we have variables, move on...
         count = 0
         for i in varlist:
             print i+'\t',
             count += 1
             if count > 8:
                 count = 0
                 print
         print
 
     def magic_whos(self, parameter_s=''):
         """Like %who, but gives some extra information about each variable.
 
         The same type filtering of %who can be applied here.
 
         For all variables, the type is printed. Additionally it prints:
         
           - For {},[],(): their length.
 
           - For numpy and Numeric arrays, a summary with shape, number of
           elements, typecode and size in memory.
 
           - Everything else: a string representation, snipping their middle if
           too long."""
         
         varnames = self.magic_who_ls(parameter_s)
         if not varnames:
             if parameter_s:
                 print 'No variables match your requested type.'
             else:
                 print 'Interactive namespace is empty.'
             return
 
         # if we have variables, move on...
 
         # for these types, show len() instead of data:
         seq_types = [types.DictType,types.ListType,types.TupleType]
 
         # for numpy/Numeric arrays, display summary info
         try:
             import numpy
         except ImportError:
             ndarray_type = None
         else:
             ndarray_type = numpy.ndarray.__name__
         try:
             import Numeric
         except ImportError:
             array_type = None
         else:
             array_type = Numeric.ArrayType.__name__
 
         # Find all variable names and types so we can figure out column sizes
         def get_vars(i):
             return self.shell.user_ns[i]
         
         # some types are well known and can be shorter
         abbrevs = {'IPython.macro.Macro' : 'Macro'}
         def type_name(v):
             tn = type(v).__name__
             return abbrevs.get(tn,tn)
             
         varlist = map(get_vars,varnames)
 
         typelist = []
         for vv in varlist:
             tt = type_name(vv)
 
             if tt=='instance':
                 typelist.append( abbrevs.get(str(vv.__class__),
                                              str(vv.__class__)))
             else:
                 typelist.append(tt)
 
         # column labels and # of spaces as separator
         varlabel = 'Variable'
         typelabel = 'Type'
         datalabel = 'Data/Info'
         colsep = 3
         # variable format strings
         vformat    = "$vname.ljust(varwidth)$vtype.ljust(typewidth)"
         vfmt_short = '$vstr[:25]<...>$vstr[-25:]'
         aformat    = "%s: %s elems, type `%s`, %s bytes"
         # find the size of the columns to format the output nicely
         varwidth = max(max(map(len,varnames)), len(varlabel)) + colsep
         typewidth = max(max(map(len,typelist)), len(typelabel)) + colsep
         # table header
         print varlabel.ljust(varwidth) + typelabel.ljust(typewidth) + \
               ' '+datalabel+'\n' + '-'*(varwidth+typewidth+len(datalabel)+1)
         # and the table itself
         kb = 1024
         Mb = 1048576  # kb**2
         for vname,var,vtype in zip(varnames,varlist,typelist):
             print itpl(vformat),
             if vtype in seq_types:
                 print len(var)
             elif vtype in [array_type,ndarray_type]:
                 vshape = str(var.shape).replace(',','').replace(' ','x')[1:-1]
                 if vtype==ndarray_type:
                     # numpy
                     vsize  = var.size
                     vbytes = vsize*var.itemsize
                     vdtype = var.dtype
                 else:
                     # Numeric
                     vsize  = Numeric.size(var)
                     vbytes = vsize*var.itemsize()
                     vdtype = var.typecode()
                     
                 if vbytes < 100000:
                     print aformat % (vshape,vsize,vdtype,vbytes)
                 else:
                     print aformat % (vshape,vsize,vdtype,vbytes),
                     if vbytes < Mb:
                         print '(%s kb)' % (vbytes/kb,)
                     else:
                         print '(%s Mb)' % (vbytes/Mb,)
             else:
                 try:
                     vstr = str(var)
                 except UnicodeEncodeError:
                     vstr = unicode(var).encode(sys.getdefaultencoding(),
                                                'backslashreplace')
                 vstr = vstr.replace('\n','\\n')
                 if len(vstr) < 50:
                     print vstr
                 else:
                     printpl(vfmt_short)
                 
     def magic_reset(self, parameter_s=''):
         """Resets the namespace by removing all names defined by the user.
 
         Input/Output history are left around in case you need them.
 
         Parameters
         ----------
           -y : force reset without asking for confirmation.
 
         Examples
         --------
         In [6]: a = 1
 
         In [7]: a
         Out[7]: 1
 
         In [8]: 'a' in _ip.user_ns
         Out[8]: True
 
         In [9]: %reset -f
 
         In [10]: 'a' in _ip.user_ns
         Out[10]: False
         """
 
         if parameter_s == '-f':
             ans = True
         else:
             ans = self.shell.ask_yes_no(
                 "Once deleted, variables cannot be recovered. Proceed (y/[n])? ")
         if not ans:
             print 'Nothing done.'
             return
         user_ns = self.shell.user_ns
         for i in self.magic_who_ls():
             del(user_ns[i])
             
         # Also flush the private list of module references kept for script
         # execution protection
         self.shell.clear_main_mod_cache()
 
     def magic_logstart(self,parameter_s=''):
         """Start logging anywhere in a session.
 
         %logstart [-o|-r|-t] [log_name [log_mode]]
 
         If no name is given, it defaults to a file named 'ipython_log.py' in your
         current directory, in 'rotate' mode (see below).
 
         '%logstart name' saves to file 'name' in 'backup' mode.  It saves your
         history up to that point and then continues logging.
 
         %logstart takes a second optional parameter: logging mode. This can be one
         of (note that the modes are given unquoted):\\
           append: well, that says it.\\
           backup: rename (if exists) to name~ and start name.\\
           global: single logfile in your home dir, appended to.\\
           over  : overwrite existing log.\\
           rotate: create rotating logs name.1~, name.2~, etc.
 
         Options:
 
           -o: log also IPython's output.  In this mode, all commands which
           generate an Out[NN] prompt are recorded to the logfile, right after
           their corresponding input line.  The output lines are always
           prepended with a '#[Out]# ' marker, so that the log remains valid
           Python code.
 
           Since this marker is always the same, filtering only the output from
           a log is very easy, using for example a simple awk call:
 
             awk -F'#\\[Out\\]# ' '{if($2) {print $2}}' ipython_log.py
 
           -r: log 'raw' input.  Normally, IPython's logs contain the processed
           input, so that user lines are logged in their final form, converted
           into valid Python.  For example, %Exit is logged as
           '_ip.magic("Exit").  If the -r flag is given, all input is logged
           exactly as typed, with no transformations applied.
 
           -t: put timestamps before each input line logged (these are put in
           comments)."""
         
         opts,par = self.parse_options(parameter_s,'ort')
         log_output = 'o' in opts
         log_raw_input = 'r' in opts
         timestamp = 't' in opts
 
         rc = self.shell.rc
         logger = self.shell.logger
 
         # if no args are given, the defaults set in the logger constructor by
         # ipytohn remain valid
         if par:
             try:
                 logfname,logmode = par.split()
             except:
                 logfname = par
                 logmode = 'backup'
         else:
             logfname = logger.logfname
             logmode = logger.logmode
         # put logfname into rc struct as if it had been called on the command
         # line, so it ends up saved in the log header Save it in case we need
         # to restore it...
         old_logfile = rc.opts.get('logfile','')  
         if logfname:
             logfname = os.path.expanduser(logfname)
         rc.opts.logfile = logfname
         loghead = self.shell.loghead_tpl % (rc.opts,rc.args)
         try:
             started  = logger.logstart(logfname,loghead,logmode,
                                        log_output,timestamp,log_raw_input)
         except:
             rc.opts.logfile = old_logfile
             warn("Couldn't start log: %s" % sys.exc_info()[1])
         else:
             # log input history up to this point, optionally interleaving
             # output if requested
 
             if timestamp:
                 # disable timestamping for the previous history, since we've
                 # lost those already (no time machine here).
                 logger.timestamp = False
 
             if log_raw_input:
                 input_hist = self.shell.input_hist_raw
             else:
                 input_hist = self.shell.input_hist
                 
             if log_output:
                 log_write = logger.log_write
                 output_hist = self.shell.output_hist
                 for n in range(1,len(input_hist)-1):
                     log_write(input_hist[n].rstrip())
                     if n in output_hist:
                         log_write(repr(output_hist[n]),'output')
             else:
                 logger.log_write(input_hist[1:])
             if timestamp:
                 # re-enable timestamping
                 logger.timestamp = True
                 
             print ('Activating auto-logging. '
                    'Current session state plus future input saved.')
             logger.logstate()
 
     def magic_logstop(self,parameter_s=''):
         """Fully stop logging and close log file.
 
         In order to start logging again, a new %logstart call needs to be made,
         possibly (though not necessarily) with a new filename, mode and other
         options."""
         self.logger.logstop()
 
     def magic_logoff(self,parameter_s=''):
         """Temporarily stop logging.
 
         You must have previously started logging."""
         self.shell.logger.switch_log(0)
         
     def magic_logon(self,parameter_s=''):
         """Restart logging.
 
         This function is for restarting logging which you've temporarily
         stopped with %logoff. For starting logging for the first time, you
         must use the %logstart function, which allows you to specify an
         optional log filename."""
         
         self.shell.logger.switch_log(1)
     
     def magic_logstate(self,parameter_s=''):
         """Print the status of the logging system."""
 
         self.shell.logger.logstate()
         
     def magic_pdb(self, parameter_s=''):
         """Control the automatic calling of the pdb interactive debugger.
 
         Call as '%pdb on', '%pdb 1', '%pdb off' or '%pdb 0'. If called without
         argument it works as a toggle.
 
         When an exception is triggered, IPython can optionally call the
         interactive pdb debugger after the traceback printout. %pdb toggles
         this feature on and off.
 
         The initial state of this feature is set in your ipythonrc
         configuration file (the variable is called 'pdb').
 
         If you want to just activate the debugger AFTER an exception has fired,
         without having to type '%pdb on' and rerunning your code, you can use
         the %debug magic."""
 
         par = parameter_s.strip().lower()
 
         if par:
             try:
                 new_pdb = {'off':0,'0':0,'on':1,'1':1}[par]
             except KeyError:
                 print ('Incorrect argument. Use on/1, off/0, '
                        'or nothing for a toggle.')
                 return
         else:
             # toggle
             new_pdb = not self.shell.call_pdb
 
         # set on the shell
         self.shell.call_pdb = new_pdb
         print 'Automatic pdb calling has been turned',on_off(new_pdb)
 
     def magic_debug(self, parameter_s=''):
         """Activate the interactive debugger in post-mortem mode.
 
         If an exception has just occurred, this lets you inspect its stack
         frames interactively.  Note that this will always work only on the last
         traceback that occurred, so you must call this quickly after an
         exception that you wish to inspect has fired, because if another one
         occurs, it clobbers the previous one.
 
         If you want IPython to automatically do this on every exception, see
         the %pdb magic for more details.
         """
         
         self.shell.debugger(force=True)
 
     @testdec.skip_doctest
     def magic_prun(self, parameter_s ='',user_mode=1,
                    opts=None,arg_lst=None,prog_ns=None):
 
         """Run a statement through the python code profiler.
 
         Usage:
           %prun [options] statement
 
         The given statement (which doesn't require quote marks) is run via the
         python profiler in a manner similar to the profile.run() function.
         Namespaces are internally managed to work correctly; profile.run
         cannot be used in IPython because it makes certain assumptions about
         namespaces which do not hold under IPython.
 
         Options:
 
         -l <limit>: you can place restrictions on what or how much of the
         profile gets printed. The limit value can be:
 
           * A string: only information for function names containing this string
           is printed.
 
           * An integer: only these many lines are printed.
 
           * A float (between 0 and 1): this fraction of the report is printed
           (for example, use a limit of 0.4 to see the topmost 40% only).
 
         You can combine several limits with repeated use of the option. For
         example, '-l __init__ -l 5' will print only the topmost 5 lines of
         information about class constructors.
 
         -r: return the pstats.Stats object generated by the profiling. This
         object has all the information about the profile in it, and you can
         later use it for further analysis or in other functions.
 
        -s <key>: sort profile by given key. You can provide more than one key
         by using the option several times: '-s key1 -s key2 -s key3...'. The
         default sorting key is 'time'.
 
         The following is copied verbatim from the profile documentation
         referenced below:
 
         When more than one key is provided, additional keys are used as
         secondary criteria when the there is equality in all keys selected
         before them.
         
         Abbreviations can be used for any key names, as long as the
         abbreviation is unambiguous.  The following are the keys currently
         defined:
 
                 Valid Arg       Meaning
                   "calls"      call count
                   "cumulative" cumulative time
                   "file"       file name
                   "module"     file name
                   "pcalls"     primitive call count
                   "line"       line number
                   "name"       function name
                   "nfl"        name/file/line
                   "stdname"    standard name
                   "time"       internal time
 
         Note that all sorts on statistics are in descending order (placing
         most time consuming items first), where as name, file, and line number
         searches are in ascending order (i.e., alphabetical). The subtle
         distinction between "nfl" and "stdname" is that the standard name is a
         sort of the name as printed, which means that the embedded line
         numbers get compared in an odd way.  For example, lines 3, 20, and 40
         would (if the file names were the same) appear in the string order
         "20" "3" and "40".  In contrast, "nfl" does a numeric compare of the
         line numbers.  In fact, sort_stats("nfl") is the same as
         sort_stats("name", "file", "line").
 
         -T <filename>: save profile results as shown on screen to a text
         file. The profile is still shown on screen.
 
         -D <filename>: save (via dump_stats) profile statistics to given
         filename. This data is in a format understod by the pstats module, and
         is generated by a call to the dump_stats() method of profile
         objects. The profile is still shown on screen.
 
         If you want to run complete programs under the profiler's control, use
         '%run -p [prof_opts] filename.py [args to program]' where prof_opts
         contains profiler specific options as described here.
         
         You can read the complete documentation for the profile module with::
         
           In [1]: import profile; profile.help()
         """
 
         opts_def = Struct(D=[''],l=[],s=['time'],T=[''])
         # protect user quote marks
         parameter_s = parameter_s.replace('"',r'\"').replace("'",r"\'")
         
         if user_mode:  # regular user call
             opts,arg_str = self.parse_options(parameter_s,'D:l:rs:T:',
                                               list_all=1)
             namespace = self.shell.user_ns
         else:  # called to run a program by %run -p
             try:
                 filename = get_py_filename(arg_lst[0])
             except IOError,msg:
                 error(msg)
                 return
 
             arg_str = 'execfile(filename,prog_ns)'
             namespace = locals()
 
         opts.merge(opts_def)
         
         prof = profile.Profile()
         try:
             prof = prof.runctx(arg_str,namespace,namespace)
             sys_exit = ''
         except SystemExit:
             sys_exit = """*** SystemExit exception caught in code being profiled."""
 
         stats = pstats.Stats(prof).strip_dirs().sort_stats(*opts.s)
 
         lims = opts.l
         if lims:
             lims = []  # rebuild lims with ints/floats/strings
             for lim in opts.l:
                 try:
                     lims.append(int(lim))
                 except ValueError:
                     try:
                         lims.append(float(lim))
                     except ValueError:
                         lims.append(lim)
                     
         # Trap output.
         stdout_trap = StringIO()
 
         if hasattr(stats,'stream'):
             # In newer versions of python, the stats object has a 'stream'
             # attribute to write into.
             stats.stream = stdout_trap
             stats.print_stats(*lims)
         else:
             # For older versions, we manually redirect stdout during printing
             sys_stdout = sys.stdout
             try:
                 sys.stdout = stdout_trap
                 stats.print_stats(*lims)
             finally:
                 sys.stdout = sys_stdout
                 
         output = stdout_trap.getvalue()
         output = output.rstrip()
 
         page(output,screen_lines=self.shell.rc.screen_length)
         print sys_exit,
 
         dump_file = opts.D[0]
         text_file = opts.T[0]
         if dump_file:
             prof.dump_stats(dump_file)
             print '\n*** Profile stats marshalled to file',\
                   `dump_file`+'.',sys_exit
         if text_file:
             pfile = file(text_file,'w')
             pfile.write(output)
             pfile.close()
             print '\n*** Profile printout saved to text file',\
                   `text_file`+'.',sys_exit
 
         if opts.has_key('r'):
             return stats
         else:
             return None
 
     @testdec.skip_doctest
     def magic_run(self, parameter_s ='',runner=None,
                   file_finder=get_py_filename):
         """Run the named file inside IPython as a program.
 
         Usage:\\
           %run [-n -i -t [-N<N>] -d [-b<N>] -p [profile options]] file [args]
         
         Parameters after the filename are passed as command-line arguments to
         the program (put in sys.argv). Then, control returns to IPython's
         prompt.
 
         This is similar to running at a system prompt:\\
           $ python file args\\
         but with the advantage of giving you IPython's tracebacks, and of
         loading all variables into your interactive namespace for further use
         (unless -p is used, see below).
 
         The file is executed in a namespace initially consisting only of
         __name__=='__main__' and sys.argv constructed as indicated. It thus
         sees its environment as if it were being run as a stand-alone program
         (except for sharing global objects such as previously imported
         modules). But after execution, the IPython interactive namespace gets
         updated with all variables defined in the program (except for __name__
         and sys.argv). This allows for very convenient loading of code for
         interactive work, while giving each program a 'clean sheet' to run in.
 
         Options:
         
         -n: __name__ is NOT set to '__main__', but to the running file's name
         without extension (as python does under import).  This allows running
         scripts and reloading the definitions in them without calling code
         protected by an ' if __name__ == "__main__" ' clause.
 
         -i: run the file in IPython's namespace instead of an empty one. This
         is useful if you are experimenting with code written in a text editor
         which depends on variables defined interactively.
 
         -e: ignore sys.exit() calls or SystemExit exceptions in the script
         being run.  This is particularly useful if IPython is being used to
         run unittests, which always exit with a sys.exit() call.  In such
         cases you are interested in the output of the test results, not in
         seeing a traceback of the unittest module.
 
         -t: print timing information at the end of the run.  IPython will give
         you an estimated CPU time consumption for your script, which under
         Unix uses the resource module to avoid the wraparound problems of
         time.clock().  Under Unix, an estimate of time spent on system tasks
         is also given (for Windows platforms this is reported as 0.0).
 
         If -t is given, an additional -N<N> option can be given, where <N>
         must be an integer indicating how many times you want the script to
         run.  The final timing report will include total and per run results.
 
         For example (testing the script uniq_stable.py):
 
             In [1]: run -t uniq_stable
 
             IPython CPU timings (estimated):\\
               User  :    0.19597 s.\\
               System:        0.0 s.\\
 
             In [2]: run -t -N5 uniq_stable
 
             IPython CPU timings (estimated):\\
             Total runs performed: 5\\
               Times :      Total       Per run\\
               User  :   0.910862 s,  0.1821724 s.\\
               System:        0.0 s,        0.0 s.
 
         -d: run your program under the control of pdb, the Python debugger.
         This allows you to execute your program step by step, watch variables,
         etc.  Internally, what IPython does is similar to calling:
         
           pdb.run('execfile("YOURFILENAME")')
 
         with a breakpoint set on line 1 of your file.  You can change the line
         number for this automatic breakpoint to be <N> by using the -bN option
         (where N must be an integer).  For example:
 
           %run -d -b40 myscript
 
         will set the first breakpoint at line 40 in myscript.py.  Note that
         the first breakpoint must be set on a line which actually does
         something (not a comment or docstring) for it to stop execution.
 
         When the pdb debugger starts, you will see a (Pdb) prompt.  You must
         first enter 'c' (without qoutes) to start execution up to the first
         breakpoint.
 
         Entering 'help' gives information about the use of the debugger.  You
         can easily see pdb's full documentation with "import pdb;pdb.help()"
         at a prompt.
 
         -p: run program under the control of the Python profiler module (which
         prints a detailed report of execution times, function calls, etc).
 
         You can pass other options after -p which affect the behavior of the
         profiler itself. See the docs for %prun for details.
 
         In this mode, the program's variables do NOT propagate back to the
         IPython interactive namespace (because they remain in the namespace
         where the profiler executes them).
 
         Internally this triggers a call to %prun, see its documentation for
         details on the options available specifically for profiling.
 
         There is one special usage for which the text above doesn't apply:
         if the filename ends with .ipy, the file is run as ipython script,
         just as if the commands were written on IPython prompt.
         """
 
         # get arguments and set sys.argv for program to be run.
         opts,arg_lst = self.parse_options(parameter_s,'nidtN:b:pD:l:rs:T:e',
                                           mode='list',list_all=1)
 
         try:
             filename = file_finder(arg_lst[0])
         except IndexError:
             warn('you must provide at least a filename.')
             print '\n%run:\n',OInspect.getdoc(self.magic_run)
             return
         except IOError,msg:
             error(msg)
             return
 
         if filename.lower().endswith('.ipy'):
             self.api.runlines(open(filename).read())
             return
         
         # Control the response to exit() calls made by the script being run
         exit_ignore = opts.has_key('e')
         
         # Make sure that the running script gets a proper sys.argv as if it
         # were run from a system shell.
         save_argv = sys.argv # save it for later restoring
         sys.argv = [filename]+ arg_lst[1:]  # put in the proper filename
 
         if opts.has_key('i'):
             # Run in user's interactive namespace
             prog_ns = self.shell.user_ns
             __name__save = self.shell.user_ns['__name__']
             prog_ns['__name__'] = '__main__'
-            main_mod = FakeModule(prog_ns)
+
+            ##main_mod = FakeModule(prog_ns)
+            main_mod = self.shell.new_main_mod(prog_ns)
+            
         else:
             # Run in a fresh, empty namespace
             if opts.has_key('n'):
                 name = os.path.splitext(os.path.basename(filename))[0]
             else:
                 name = '__main__'
-            main_mod = FakeModule()
+
+            main_mod = self.shell.new_main_mod()
+            
             prog_ns = main_mod.__dict__
             prog_ns['__name__'] = name
             
-            # The shell MUST hold a reference to main_mod so after %run exits,
-            # the python deletion mechanism doesn't zero it out (leaving
-            # dangling references).  However, we should drop old versions of
-            # main_mod.  There is now a proper API to manage this caching in
-            # the main shell object, we use that.            
-            self.shell.cache_main_mod(main_mod)
 
         # Since '%run foo' emulates 'python foo.py' at the cmd line, we must
         # set the __file__ global in the script's namespace
         prog_ns['__file__'] = filename
 
         # pickle fix.  See iplib for an explanation.  But we need to make sure
         # that, if we overwrite __main__, we replace it at the end
         main_mod_name = prog_ns['__name__']
 
         if main_mod_name == '__main__':
             restore_main = sys.modules['__main__']
         else:
             restore_main = False
 
         # This needs to be undone at the end to prevent holding references to
         # every single object ever created.
         sys.modules[main_mod_name] = main_mod
         
         stats = None
         try:
             self.shell.savehist()
 
             if opts.has_key('p'):
                 stats = self.magic_prun('',0,opts,arg_lst,prog_ns)
             else:
                 if opts.has_key('d'):
                     deb = Debugger.Pdb(self.shell.rc.colors)
                     # reset Breakpoint state, which is moronically kept
                     # in a class
                     bdb.Breakpoint.next = 1
                     bdb.Breakpoint.bplist = {}
                     bdb.Breakpoint.bpbynumber = [None]
                     # Set an initial breakpoint to stop execution
                     maxtries = 10
                     bp = int(opts.get('b',[1])[0])
                     checkline = deb.checkline(filename,bp)
                     if not checkline:
                         for bp in range(bp+1,bp+maxtries+1):
                             if deb.checkline(filename,bp):
                                 break
                         else:
                             msg = ("\nI failed to find a valid line to set "
                                    "a breakpoint\n"
                                    "after trying up to line: %s.\n"
                                    "Please set a valid breakpoint manually "
                                    "with the -b option." % bp)
                             error(msg)
                             return
                     # if we find a good linenumber, set the breakpoint
                     deb.do_break('%s:%s' % (filename,bp))
                     # Start file run
                     print "NOTE: Enter 'c' at the",
                     print "%s prompt to start your script." % deb.prompt
                     try:
                         deb.run('execfile("%s")' % filename,prog_ns)
                         
                     except:
                         etype, value, tb = sys.exc_info()
                         # Skip three frames in the traceback: the %run one,
                         # one inside bdb.py, and the command-line typed by the
                         # user (run by exec in pdb itself).
                         self.shell.InteractiveTB(etype,value,tb,tb_offset=3)
                 else:
                     if runner is None:
                         runner = self.shell.safe_execfile
                     if opts.has_key('t'):
                         # timed execution
                         try:
                             nruns = int(opts['N'][0])
                             if nruns < 1:
                                 error('Number of runs must be >=1')
                                 return
                         except (KeyError):
                             nruns = 1
                         if nruns == 1:
                             t0 = clock2()
                             runner(filename,prog_ns,prog_ns,
                                    exit_ignore=exit_ignore)
                             t1 = clock2()
                             t_usr = t1[0]-t0[0]
                             t_sys = t1[1]-t1[1]
                             print "\nIPython CPU timings (estimated):"
                             print "  User  : %10s s." % t_usr
                             print "  System: %10s s." % t_sys
                         else:
                             runs = range(nruns)
                             t0 = clock2()
                             for nr in runs:
                                 runner(filename,prog_ns,prog_ns,
                                        exit_ignore=exit_ignore)
                             t1 = clock2()
                             t_usr = t1[0]-t0[0]
                             t_sys = t1[1]-t1[1]
                             print "\nIPython CPU timings (estimated):"
                             print "Total runs performed:",nruns
                             print "  Times : %10s    %10s" % ('Total','Per run')
                             print "  User  : %10s s, %10s s." % (t_usr,t_usr/nruns)
                             print "  System: %10s s, %10s s." % (t_sys,t_sys/nruns)
                             
                     else:
                         # regular execution
                         runner(filename,prog_ns,prog_ns,exit_ignore=exit_ignore)
+
                 if opts.has_key('i'):
                     self.shell.user_ns['__name__'] = __name__save
                 else:
+                    # The shell MUST hold a reference to prog_ns so after %run
+                    # exits, the python deletion mechanism doesn't zero it out
+                    # (leaving dangling references).
+                    self.shell.cache_main_mod(prog_ns,filename)
                     # update IPython interactive namespace
                     del prog_ns['__name__']
                     self.shell.user_ns.update(prog_ns)
         finally:
             # Ensure key global structures are restored
             sys.argv = save_argv
             if restore_main:
                 sys.modules['__main__'] = restore_main
             else:
                 # Remove from sys.modules the reference to main_mod we'd
                 # added.  Otherwise it will trap references to objects
                 # contained therein.
                 del sys.modules[main_mod_name]
+
             self.shell.reloadhist()
                 
         return stats
 
     def magic_runlog(self, parameter_s =''):
         """Run files as logs.
 
         Usage:\\
           %runlog file1 file2 ...
 
         Run the named files (treating them as log files) in sequence inside
         the interpreter, and return to the prompt.  This is much slower than
         %run because each line is executed in a try/except block, but it
         allows running files with syntax errors in them.
 
         Normally IPython will guess when a file is one of its own logfiles, so
         you can typically use %run even for logs. This shorthand allows you to
         force any file to be treated as a log file."""
 
         for f in parameter_s.split():
             self.shell.safe_execfile(f,self.shell.user_ns,
                                      self.shell.user_ns,islog=1)
 
     @testdec.skip_doctest
     def magic_timeit(self, parameter_s =''):
         """Time execution of a Python statement or expression
 
         Usage:\\
           %timeit [-n<N> -r<R> [-t|-c]] statement
 
         Time execution of a Python statement or expression using the timeit
         module.
 
         Options:
         -n<N>: execute the given statement <N> times in a loop. If this value
         is not given, a fitting value is chosen. 
         
         -r<R>: repeat the loop iteration <R> times and take the best result.
         Default: 3
         
         -t: use time.time to measure the time, which is the default on Unix.
         This function measures wall time.
         
         -c: use time.clock to measure the time, which is the default on
         Windows and measures wall time. On Unix, resource.getrusage is used
         instead and returns the CPU user time.
 
         -p<P>: use a precision of <P> digits to display the timing result.
         Default: 3
 
         
         Examples:
 
           In [1]: %timeit pass
           10000000 loops, best of 3: 53.3 ns per loop
 
           In [2]: u = None
 
           In [3]: %timeit u is None
           10000000 loops, best of 3: 184 ns per loop
 
           In [4]: %timeit -r 4 u == None
           1000000 loops, best of 4: 242 ns per loop
 
           In [5]: import time
 
           In [6]: %timeit -n1 time.sleep(2)
           1 loops, best of 3: 2 s per loop
           
 
         The times reported by %timeit will be slightly higher than those
         reported by the timeit.py script when variables are accessed. This is
         due to the fact that %timeit executes the statement in the namespace
         of the shell, compared with timeit.py, which uses a single setup
         statement to import function or create variables. Generally, the bias
         does not matter as long as results from timeit.py are not mixed with
         those from %timeit."""
 
         import timeit
         import math
 
         # XXX: Unfortunately the unicode 'micro' symbol can cause problems in
         # certain terminals.  Until we figure out a robust way of
         # auto-detecting if the terminal can deal with it, use plain 'us' for
         # microseconds.  Note: using
         #
         # s = u'\xb5'
         # s.encode(sys.getdefaultencoding())
         #
         # is not sufficient, as I've seen terminals where that fails but
         # print s
         #
         # succeeds
         #
         # See bug: https://bugs.launchpad.net/ipython/+bug/348466
         
         #units = [u"s", u"ms",u'\xb5',"ns"]
         units = [u"s", u"ms",u'us',"ns"]
         
         scaling = [1, 1e3, 1e6, 1e9]
 
         opts, stmt = self.parse_options(parameter_s,'n:r:tcp:',
                                         posix=False)
         if stmt == "":
             return
         timefunc = timeit.default_timer
         number = int(getattr(opts, "n", 0))
         repeat = int(getattr(opts, "r", timeit.default_repeat))
         precision = int(getattr(opts, "p", 3))
         if hasattr(opts, "t"):
             timefunc = time.time
         if hasattr(opts, "c"):
             timefunc = clock
 
         timer = timeit.Timer(timer=timefunc)
         # this code has tight coupling to the inner workings of timeit.Timer,
         # but is there a better way to achieve that the code stmt has access
         # to the shell namespace?
 
         src = timeit.template % {'stmt': timeit.reindent(stmt, 8),
                                  'setup': "pass"}
         # Track compilation time so it can be reported if too long
         # Minimum time above which compilation time will be reported
         tc_min = 0.1
         
         t0 = clock()
         code = compile(src, "<magic-timeit>", "exec")
         tc = clock()-t0
         
         ns = {}
         exec code in self.shell.user_ns, ns
         timer.inner = ns["inner"]
         
         if number == 0:
             # determine number so that 0.2 <= total time < 2.0
             number = 1
             for i in range(1, 10):
                 number *= 10
                 if timer.timeit(number) >= 0.2:
                     break
         
         best = min(timer.repeat(repeat, number)) / number
 
         if best > 0.0:
             order = min(-int(math.floor(math.log10(best)) // 3), 3)
         else:
             order = 3
         print u"%d loops, best of %d: %.*g %s per loop" % (number, repeat,
                                                           precision,
                                                           best * scaling[order],
                                                           units[order])
         if tc > tc_min:
             print "Compiler time: %.2f s" % tc
 
     @testdec.skip_doctest
     def magic_time(self,parameter_s = ''):
         """Time execution of a Python statement or expression.
 
         The CPU and wall clock times are printed, and the value of the
         expression (if any) is returned.  Note that under Win32, system time
         is always reported as 0, since it can not be measured.
 
         This function provides very basic timing functionality.  In Python
         2.3, the timeit module offers more control and sophistication, so this
         could be rewritten to use it (patches welcome).
         
         Some examples:
 
           In [1]: time 2**128
           CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
           Wall time: 0.00
           Out[1]: 340282366920938463463374607431768211456L
 
           In [2]: n = 1000000
 
           In [3]: time sum(range(n))
           CPU times: user 1.20 s, sys: 0.05 s, total: 1.25 s
           Wall time: 1.37
           Out[3]: 499999500000L
 
           In [4]: time print 'hello world'
           hello world
           CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
           Wall time: 0.00
 
           Note that the time needed by Python to compile the given expression
           will be reported if it is more than 0.1s.  In this example, the
           actual exponentiation is done by Python at compilation time, so while
           the expression can take a noticeable amount of time to compute, that
           time is purely due to the compilation:
 
           In [5]: time 3**9999;
           CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
           Wall time: 0.00 s
 
           In [6]: time 3**999999;
           CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
           Wall time: 0.00 s
           Compiler : 0.78 s
           """
         
         # fail immediately if the given expression can't be compiled
         
         expr = self.shell.prefilter(parameter_s,False)
 
         # Minimum time above which compilation time will be reported
         tc_min = 0.1
         
         try:
             mode = 'eval'
             t0 = clock()
             code = compile(expr,'<timed eval>',mode)
             tc = clock()-t0
         except SyntaxError:
             mode = 'exec'
             t0 = clock()
             code = compile(expr,'<timed exec>',mode)
             tc = clock()-t0
         # skew measurement as little as possible
         glob = self.shell.user_ns
         clk = clock2
         wtime = time.time
         # time execution
         wall_st = wtime()
         if mode=='eval':
             st = clk()
             out = eval(code,glob)
             end = clk()
         else:
             st = clk()
             exec code in glob
             end = clk()
             out = None
         wall_end = wtime()
         # Compute actual times and report
         wall_time = wall_end-wall_st
         cpu_user = end[0]-st[0]
         cpu_sys = end[1]-st[1]
         cpu_tot = cpu_user+cpu_sys
         print "CPU times: user %.2f s, sys: %.2f s, total: %.2f s" % \
               (cpu_user,cpu_sys,cpu_tot)
         print "Wall time: %.2f s" % wall_time
         if tc > tc_min:
             print "Compiler : %.2f s" % tc
         return out
 
     @testdec.skip_doctest
     def magic_macro(self,parameter_s = ''):
         """Define a set of input lines as a macro for future re-execution.
 
         Usage:\\
           %macro [options] name n1-n2 n3-n4 ... n5 .. n6 ...
 
         Options:
         
           -r: use 'raw' input.  By default, the 'processed' history is used,
           so that magics are loaded in their transformed version to valid
           Python.  If this option is given, the raw input as typed as the
           command line is used instead.
 
         This will define a global variable called `name` which is a string
         made of joining the slices and lines you specify (n1,n2,... numbers
         above) from your input history into a single string. This variable
         acts like an automatic function which re-executes those lines as if
         you had typed them. You just type 'name' at the prompt and the code
         executes.
 
         The notation for indicating number ranges is: n1-n2 means 'use line
         numbers n1,...n2' (the endpoint is included).  That is, '5-7' means
         using the lines numbered 5,6 and 7.
 
         Note: as a 'hidden' feature, you can also use traditional python slice
         notation, where N:M means numbers N through M-1.
 
         For example, if your history contains (%hist prints it):
         
           44: x=1
           45: y=3
           46: z=x+y
           47: print x
           48: a=5
           49: print 'x',x,'y',y
 
         you can create a macro with lines 44 through 47 (included) and line 49
         called my_macro with:
 
           In [55]: %macro my_macro 44-47 49
 
         Now, typing `my_macro` (without quotes) will re-execute all this code
         in one pass.
 
         You don't need to give the line-numbers in order, and any given line
         number can appear multiple times. You can assemble macros with any
         lines from your input history in any order.
 
         The macro is a simple object which holds its value in an attribute,
         but IPython's display system checks for macros and executes them as
         code instead of printing them when you type their name.
 
         You can view a macro's contents by explicitly printing it with:
         
           'print macro_name'.
 
         For one-off cases which DON'T contain magic function calls in them you
         can obtain similar results by explicitly executing slices from your
         input history with:
 
           In [60]: exec In[44:48]+In[49]"""
 
         opts,args = self.parse_options(parameter_s,'r',mode='list')
         if not args:
             macs = [k for k,v in self.shell.user_ns.items() if isinstance(v, Macro)]
             macs.sort()
             return macs
         if len(args) == 1:
             raise UsageError(
                 "%macro insufficient args; usage '%macro name n1-n2 n3-4...")
         name,ranges = args[0], args[1:]
         
         #print 'rng',ranges  # dbg
         lines = self.extract_input_slices(ranges,opts.has_key('r'))
         macro = Macro(lines)
         self.shell.user_ns.update({name:macro})
         print 'Macro `%s` created. To execute, type its name (without quotes).' % name
         print 'Macro contents:'
         print macro,
 
     def magic_save(self,parameter_s = ''):
         """Save a set of lines to a given filename.
 
         Usage:\\
           %save [options] filename n1-n2 n3-n4 ... n5 .. n6 ...
 
         Options:
         
           -r: use 'raw' input.  By default, the 'processed' history is used,
           so that magics are loaded in their transformed version to valid
           Python.  If this option is given, the raw input as typed as the
           command line is used instead.
 
         This function uses the same syntax as %macro for line extraction, but
         instead of creating a macro it saves the resulting string to the
         filename you specify.
 
         It adds a '.py' extension to the file if you don't do so yourself, and
         it asks for confirmation before overwriting existing files."""
 
         opts,args = self.parse_options(parameter_s,'r',mode='list')
         fname,ranges = args[0], args[1:]
         if not fname.endswith('.py'):
             fname += '.py'
         if os.path.isfile(fname):
             ans = raw_input('File `%s` exists. Overwrite (y/[N])? ' % fname)
             if ans.lower() not in ['y','yes']:
                 print 'Operation cancelled.'
                 return
         cmds = ''.join(self.extract_input_slices(ranges,opts.has_key('r')))
         f = file(fname,'w')
         f.write(cmds)
         f.close()
         print 'The following commands were written to file `%s`:' % fname
         print cmds
 
     def _edit_macro(self,mname,macro):
         """open an editor with the macro data in a file"""
         filename = self.shell.mktempfile(macro.value)
         self.shell.hooks.editor(filename)
 
         # and make a new macro object, to replace the old one
         mfile = open(filename)
         mvalue = mfile.read()
         mfile.close()
         self.shell.user_ns[mname] = Macro(mvalue)
 
     def magic_ed(self,parameter_s=''):
         """Alias to %edit."""
         return self.magic_edit(parameter_s)
 
     @testdec.skip_doctest
     def magic_edit(self,parameter_s='',last_call=['','']):
         """Bring up an editor and execute the resulting code.
 
         Usage:
           %edit [options] [args]
 
         %edit runs IPython's editor hook.  The default version of this hook is
         set to call the __IPYTHON__.rc.editor command.  This is read from your
         environment variable $EDITOR.  If this isn't found, it will default to
         vi under Linux/Unix and to notepad under Windows.  See the end of this
         docstring for how to change the editor hook.
 
         You can also set the value of this editor via the command line option
         '-editor' or in your ipythonrc file. This is useful if you wish to use
         specifically for IPython an editor different from your typical default
         (and for Windows users who typically don't set environment variables).
 
         This command allows you to conveniently edit multi-line code right in
         your IPython session.
         
         If called without arguments, %edit opens up an empty editor with a
         temporary file and will execute the contents of this file when you
         close it (don't forget to save it!).
 
 
         Options:
 
         -n <number>: open the editor at a specified line number.  By default,
         the IPython editor hook uses the unix syntax 'editor +N filename', but
         you can configure this by providing your own modified hook if your
         favorite editor supports line-number specifications with a different
         syntax.
         
         -p: this will call the editor with the same data as the previous time
         it was used, regardless of how long ago (in your current session) it
         was.
 
         -r: use 'raw' input.  This option only applies to input taken from the
         user's history.  By default, the 'processed' history is used, so that
         magics are loaded in their transformed version to valid Python.  If
         this option is given, the raw input as typed as the command line is
         used instead.  When you exit the editor, it will be executed by
         IPython's own processor.
         
         -x: do not execute the edited code immediately upon exit. This is
         mainly useful if you are editing programs which need to be called with
         command line arguments, which you can then do using %run.
 
 
         Arguments:
 
         If arguments are given, the following possibilites exist:
 
         - The arguments are numbers or pairs of colon-separated numbers (like
         1 4:8 9). These are interpreted as lines of previous input to be
         loaded into the editor. The syntax is the same of the %macro command.
 
         - If the argument doesn't start with a number, it is evaluated as a
         variable and its contents loaded into the editor. You can thus edit
         any string which contains python code (including the result of
         previous edits).
 
         - If the argument is the name of an object (other than a string),
         IPython will try to locate the file where it was defined and open the
         editor at the point where it is defined. You can use `%edit function`
         to load an editor exactly at the point where 'function' is defined,
         edit it and have the file be executed automatically.
 
         If the object is a macro (see %macro for details), this opens up your
         specified editor with a temporary file containing the macro's data.
         Upon exit, the macro is reloaded with the contents of the file.
 
         Note: opening at an exact line is only supported under Unix, and some
         editors (like kedit and gedit up to Gnome 2.8) do not understand the
         '+NUMBER' parameter necessary for this feature. Good editors like
         (X)Emacs, vi, jed, pico and joe all do.
 
         - If the argument is not found as a variable, IPython will look for a
         file with that name (adding .py if necessary) and load it into the
         editor. It will execute its contents with execfile() when you exit,
         loading any code in the file into your interactive namespace.
 
         After executing your code, %edit will return as output the code you
         typed in the editor (except when it was an existing file). This way
         you can reload the code in further invocations of %edit as a variable,
         via _<NUMBER> or Out[<NUMBER>], where <NUMBER> is the prompt number of
         the output.
 
         Note that %edit is also available through the alias %ed.
 
         This is an example of creating a simple function inside the editor and
         then modifying it. First, start up the editor:
 
         In [1]: ed
         Editing... done. Executing edited code...
         Out[1]: 'def foo():n    print "foo() was defined in an editing session"n'
 
         We can then call the function foo():
         
         In [2]: foo()
         foo() was defined in an editing session
 
         Now we edit foo.  IPython automatically loads the editor with the
         (temporary) file where foo() was previously defined:
         
         In [3]: ed foo
         Editing... done. Executing edited code...
 
         And if we call foo() again we get the modified version:
         
         In [4]: foo()
         foo() has now been changed!
 
         Here is an example of how to edit a code snippet successive
         times. First we call the editor:
 
         In [5]: ed
         Editing... done. Executing edited code...
         hello
         Out[5]: "print 'hello'n"
 
         Now we call it again with the previous output (stored in _):
 
         In [6]: ed _
         Editing... done. Executing edited code...
         hello world
         Out[6]: "print 'hello world'n"
 
         Now we call it with the output #8 (stored in _8, also as Out[8]):
 
         In [7]: ed _8
         Editing... done. Executing edited code...
         hello again
         Out[7]: "print 'hello again'n"
 
 
         Changing the default editor hook:
 
         If you wish to write your own editor hook, you can put it in a
         configuration file which you load at startup time.  The default hook
         is defined in the IPython.hooks module, and you can use that as a
         starting example for further modifications.  That file also has
         general instructions on how to set a new hook for use once you've
         defined it."""
         
         # FIXME: This function has become a convoluted mess.  It needs a
         # ground-up rewrite with clean, simple logic.
 
         def make_filename(arg):
             "Make a filename from the given args"
             try:
                 filename = get_py_filename(arg)
             except IOError:
                 if args.endswith('.py'):
                     filename = arg
                 else:
                     filename = None
             return filename
 
         # custom exceptions
         class DataIsObject(Exception): pass
 
         opts,args = self.parse_options(parameter_s,'prxn:')
         # Set a few locals from the options for convenience:
         opts_p = opts.has_key('p')
         opts_r = opts.has_key('r')
         
         # Default line number value
         lineno = opts.get('n',None)
 
         if opts_p:
             args = '_%s' % last_call[0]
             if not self.shell.user_ns.has_key(args):
                 args = last_call[1]
             
         # use last_call to remember the state of the previous call, but don't
         # let it be clobbered by successive '-p' calls.
         try:
             last_call[0] = self.shell.outputcache.prompt_count
             if not opts_p:
                 last_call[1] = parameter_s
         except:
             pass
 
         # by default this is done with temp files, except when the given
         # arg is a filename
         use_temp = 1
 
         if re.match(r'\d',args):
             # Mode where user specifies ranges of lines, like in %macro.
             # This means that you can't edit files whose names begin with
             # numbers this way. Tough.
             ranges = args.split()
             data = ''.join(self.extract_input_slices(ranges,opts_r))
         elif args.endswith('.py'):
             filename = make_filename(args)
             data = ''
             use_temp = 0
         elif args:
             try:
                 # Load the parameter given as a variable. If not a string,
                 # process it as an object instead (below)
 
                 #print '*** args',args,'type',type(args)  # dbg
                 data = eval(args,self.shell.user_ns)
                 if not type(data) in StringTypes:
                     raise DataIsObject
 
             except (NameError,SyntaxError):
                 # given argument is not a variable, try as a filename
                 filename = make_filename(args)
                 if filename is None:
                     warn("Argument given (%s) can't be found as a variable "
                          "or as a filename." % args)
                     return
 
                 data = ''
                 use_temp = 0
             except DataIsObject:
 
                 # macros have a special edit function
                 if isinstance(data,Macro):
                     self._edit_macro(args,data)
                     return
                                 
                 # For objects, try to edit the file where they are defined
                 try:
                     filename = inspect.getabsfile(data)
                     if 'fakemodule' in filename.lower() and inspect.isclass(data):                     
                         # class created by %edit? Try to find source
                         # by looking for method definitions instead, the
                         # __module__ in those classes is FakeModule.
                         attrs = [getattr(data, aname) for aname in dir(data)]
                         for attr in attrs:
                             if not inspect.ismethod(attr):
                                 continue
                             filename = inspect.getabsfile(attr)
                             if filename and 'fakemodule' not in filename.lower():
                                 # change the attribute to be the edit target instead
                                 data = attr 
                                 break
                     
                     datafile = 1
                 except TypeError:
                     filename = make_filename(args)
                     datafile = 1
                     warn('Could not find file where `%s` is defined.\n'
                          'Opening a file named `%s`' % (args,filename))
                 # Now, make sure we can actually read the source (if it was in
                 # a temp file it's gone by now).
                 if datafile:
                     try:
                         if lineno is None:
                             lineno = inspect.getsourcelines(data)[1]
                     except IOError:
                         filename = make_filename(args)
                         if filename is None:
                             warn('The file `%s` where `%s` was defined cannot '
                                  'be read.' % (filename,data))
                             return
                 use_temp = 0
         else:
             data = ''
 
         if use_temp:
             filename = self.shell.mktempfile(data)
             print 'IPython will make a temporary file named:',filename
 
         # do actual editing here
         print 'Editing...',
         sys.stdout.flush()
         try:
             self.shell.hooks.editor(filename,lineno)
         except IPython.ipapi.TryNext:
             warn('Could not open editor')
             return
         
         # XXX TODO: should this be generalized for all string vars?
         # For now, this is special-cased to blocks created by cpaste
         if args.strip() == 'pasted_block':
             self.shell.user_ns['pasted_block'] = file_read(filename)
         
         if opts.has_key('x'):  # -x prevents actual execution
             print
         else:
             print 'done. Executing edited code...'
             if opts_r:
                 self.shell.runlines(file_read(filename))
             else:
                 self.shell.safe_execfile(filename,self.shell.user_ns,
                                          self.shell.user_ns)
         
                                                      
         if use_temp:
             try:
                 return open(filename).read()
             except IOError,msg:
                 if msg.filename == filename:
                     warn('File not found. Did you forget to save?')
                     return
                 else:
                     self.shell.showtraceback()
 
     def magic_xmode(self,parameter_s = ''):
         """Switch modes for the exception handlers.
 
         Valid modes: Plain, Context and Verbose.
 
         If called without arguments, acts as a toggle."""
 
         def xmode_switch_err(name):
             warn('Error changing %s exception modes.\n%s' %
                  (name,sys.exc_info()[1]))
 
         shell = self.shell
         new_mode = parameter_s.strip().capitalize()
         try:
             shell.InteractiveTB.set_mode(mode=new_mode)
             print 'Exception reporting mode:',shell.InteractiveTB.mode
         except:
             xmode_switch_err('user')
 
         # threaded shells use a special handler in sys.excepthook
         if shell.isthreaded:
             try:
                 shell.sys_excepthook.set_mode(mode=new_mode)
             except:
                 xmode_switch_err('threaded')
             
     def magic_colors(self,parameter_s = ''):
         """Switch color scheme for prompts, info system and exception handlers.
 
         Currently implemented schemes: NoColor, Linux, LightBG.
 
         Color scheme names are not case-sensitive."""
 
         def color_switch_err(name):
             warn('Error changing %s color schemes.\n%s' %
                  (name,sys.exc_info()[1]))
             
         
         new_scheme = parameter_s.strip()
         if not new_scheme:
             raise UsageError(
                 "%colors: you must specify a color scheme. See '%colors?'")
             return
         # local shortcut
         shell = self.shell
 
         import IPython.rlineimpl as readline
 
         if not readline.have_readline and sys.platform == "win32":
             msg = """\
 Proper color support under MS Windows requires the pyreadline library.
 You can find it at:
 http://ipython.scipy.org/moin/PyReadline/Intro
 Gary's readline needs the ctypes module, from:
 http://starship.python.net/crew/theller/ctypes
 (Note that ctypes is already part of Python versions 2.5 and newer).
 
 Defaulting color scheme to 'NoColor'"""
             new_scheme = 'NoColor'
             warn(msg)
         
         # readline option is 0
         if not shell.has_readline:
             new_scheme = 'NoColor'
             
         # Set prompt colors
         try:
             shell.outputcache.set_colors(new_scheme)
         except:
             color_switch_err('prompt')
         else:
             shell.rc.colors = \
                        shell.outputcache.color_table.active_scheme_name
         # Set exception colors
         try:
             shell.InteractiveTB.set_colors(scheme = new_scheme)
             shell.SyntaxTB.set_colors(scheme = new_scheme)
         except:
             color_switch_err('exception')
 
         # threaded shells use a verbose traceback in sys.excepthook
         if shell.isthreaded:
             try:
                 shell.sys_excepthook.set_colors(scheme=new_scheme)
             except:
                 color_switch_err('system exception handler')
         
         # Set info (for 'object?') colors
         if shell.rc.color_info:
             try:
                 shell.inspector.set_active_scheme(new_scheme)
             except:
                 color_switch_err('object inspector')
         else:
             shell.inspector.set_active_scheme('NoColor')
                 
     def magic_color_info(self,parameter_s = ''):
         """Toggle color_info.
 
         The color_info configuration parameter controls whether colors are
         used for displaying object details (by things like %psource, %pfile or
         the '?' system). This function toggles this value with each call.
 
         Note that unless you have a fairly recent pager (less works better
         than more) in your system, using colored object information displays
         will not work properly. Test it and see."""
         
         self.shell.rc.color_info = 1 - self.shell.rc.color_info
         self.magic_colors(self.shell.rc.colors)
         print 'Object introspection functions have now coloring:',
         print ['OFF','ON'][self.shell.rc.color_info]
 
     def magic_Pprint(self, parameter_s=''):
         """Toggle pretty printing on/off."""
         
         self.shell.rc.pprint = 1 - self.shell.rc.pprint
         print 'Pretty printing has been turned', \
               ['OFF','ON'][self.shell.rc.pprint]
         
     def magic_exit(self, parameter_s=''):
         """Exit IPython, confirming if configured to do so.
 
         You can configure whether IPython asks for confirmation upon exit by
         setting the confirm_exit flag in the ipythonrc file."""
 
         self.shell.exit()
 
     def magic_quit(self, parameter_s=''):
         """Exit IPython, confirming if configured to do so (like %exit)"""
 
         self.shell.exit()
         
     def magic_Exit(self, parameter_s=''):
         """Exit IPython without confirmation."""
 
         self.shell.ask_exit()
 
     #......................................................................
     # Functions to implement unix shell-type things
 
     @testdec.skip_doctest
     def magic_alias(self, parameter_s = ''):
         """Define an alias for a system command.
 
         '%alias alias_name cmd' defines 'alias_name' as an alias for 'cmd'
 
         Then, typing 'alias_name params' will execute the system command 'cmd
         params' (from your underlying operating system).
 
         Aliases have lower precedence than magic functions and Python normal
         variables, so if 'foo' is both a Python variable and an alias, the
         alias can not be executed until 'del foo' removes the Python variable.
 
         You can use the %l specifier in an alias definition to represent the
         whole line when the alias is called.  For example:
 
           In [2]: alias all echo "Input in brackets: <%l>"
           In [3]: all hello world
           Input in brackets: <hello world>
 
         You can also define aliases with parameters using %s specifiers (one
         per parameter):
         
           In [1]: alias parts echo first %s second %s
           In [2]: %parts A B
           first A second B
           In [3]: %parts A
           Incorrect number of arguments: 2 expected.
           parts is an alias to: 'echo first %s second %s'
 
         Note that %l and %s are mutually exclusive.  You can only use one or
         the other in your aliases.
 
         Aliases expand Python variables just like system calls using ! or !! 
         do: all expressions prefixed with '$' get expanded.  For details of
         the semantic rules, see PEP-215:
         http://www.python.org/peps/pep-0215.html.  This is the library used by
         IPython for variable expansion.  If you want to access a true shell
         variable, an extra $ is necessary to prevent its expansion by IPython:
 
         In [6]: alias show echo
         In [7]: PATH='A Python string'
         In [8]: show $PATH
         A Python string
         In [9]: show $$PATH
         /usr/local/lf9560/bin:/usr/local/intel/compiler70/ia32/bin:...
 
         You can use the alias facility to acess all of $PATH.  See the %rehash
         and %rehashx functions, which automatically create aliases for the
         contents of your $PATH.
 
         If called with no parameters, %alias prints the current alias table."""
 
         par = parameter_s.strip()
         if not par:
             stored = self.db.get('stored_aliases', {} )
             atab = self.shell.alias_table
             aliases = atab.keys()
             aliases.sort()
             res = []
             showlast = []
             for alias in aliases:
                 special = False
                 try:
                     tgt = atab[alias][1]
                 except (TypeError, AttributeError):
                     # unsubscriptable? probably a callable
                     tgt = atab[alias]
                     special = True
                 # 'interesting' aliases
                 if (alias in stored or
                     special or 
                     alias.lower() != os.path.splitext(tgt)[0].lower() or
                     ' ' in tgt):
                     showlast.append((alias, tgt))
                 else:
                     res.append((alias, tgt ))                
             
             # show most interesting aliases last
             res.extend(showlast)
             print "Total number of aliases:",len(aliases)
             return res
         try:
             alias,cmd = par.split(None,1)
         except:
             print OInspect.getdoc(self.magic_alias)
         else:
             nargs = cmd.count('%s')
             if nargs>0 and cmd.find('%l')>=0:
                 error('The %s and %l specifiers are mutually exclusive '
                       'in alias definitions.')
             else:  # all looks OK
                 self.shell.alias_table[alias] = (nargs,cmd)
                 self.shell.alias_table_validate(verbose=0)
     # end magic_alias
 
     def magic_unalias(self, parameter_s = ''):
         """Remove an alias"""
 
         aname = parameter_s.strip()
         if aname in self.shell.alias_table:
             del self.shell.alias_table[aname]
         stored = self.db.get('stored_aliases', {} )
         if aname in stored:
             print "Removing %stored alias",aname
             del stored[aname]
             self.db['stored_aliases'] = stored
             
 
     def magic_rehashx(self, parameter_s = ''):
         """Update the alias table with all executable files in $PATH.
 
         This version explicitly checks that every entry in $PATH is a file
         with execute access (os.X_OK), so it is much slower than %rehash.
 
         Under Windows, it checks executability as a match agains a
         '|'-separated string of extensions, stored in the IPython config
         variable win_exec_ext.  This defaults to 'exe|com|bat'.
         
         This function also resets the root module cache of module completer,
         used on slow filesystems.
         """
         
         
         ip = self.api
 
         # for the benefit of module completer in ipy_completers.py
         del ip.db['rootmodules']
         
         path = [os.path.abspath(os.path.expanduser(p)) for p in 
             os.environ.get('PATH','').split(os.pathsep)]
         path = filter(os.path.isdir,path)
         
         alias_table = self.shell.alias_table
         syscmdlist = []
         if os.name == 'posix':
             isexec = lambda fname:os.path.isfile(fname) and \
                      os.access(fname,os.X_OK)
         else:
 
             try:
                 winext = os.environ['pathext'].replace(';','|').replace('.','')
             except KeyError:
                 winext = 'exe|com|bat|py'
             if 'py' not in winext:
                 winext += '|py'
             execre = re.compile(r'(.*)\.(%s)$' % winext,re.IGNORECASE)
             isexec = lambda fname:os.path.isfile(fname) and execre.match(fname)
         savedir = os.getcwd()
         try:
             # write the whole loop for posix/Windows so we don't have an if in
             # the innermost part
             if os.name == 'posix':
                 for pdir in path:
                     os.chdir(pdir)
                     for ff in os.listdir(pdir):
                         if isexec(ff) and ff not in self.shell.no_alias:
                             # each entry in the alias table must be (N,name),
                             # where N is the number of positional arguments of the
                             # alias.                            
                             # Dots will be removed from alias names, since ipython
                             # assumes names with dots to be python code
                             alias_table[ff.replace('.','')] = (0,ff)
                             syscmdlist.append(ff)
             else:
                 for pdir in path:
                     os.chdir(pdir)
                     for ff in os.listdir(pdir):
                         base, ext = os.path.splitext(ff)
                         if isexec(ff) and base.lower() not in self.shell.no_alias:
                             if ext.lower() == '.exe':
                                 ff = base
                             alias_table[base.lower().replace('.','')] = (0,ff)
                             syscmdlist.append(ff)
             # Make sure the alias table doesn't contain keywords or builtins
             self.shell.alias_table_validate()
             # Call again init_auto_alias() so we get 'rm -i' and other
             # modified aliases since %rehashx will probably clobber them
             
             # no, we don't want them. if %rehashx clobbers them, good,
             # we'll probably get better versions
             # self.shell.init_auto_alias()
             db = ip.db
             db['syscmdlist'] = syscmdlist
         finally:
             os.chdir(savedir)
         
     def magic_pwd(self, parameter_s = ''):
         """Return the current working directory path."""
         return os.getcwd()
 
     def magic_cd(self, parameter_s=''):
         """Change the current working directory.
 
         This command automatically maintains an internal list of directories
         you visit during your IPython session, in the variable _dh. The
         command %dhist shows this history nicely formatted. You can also
         do 'cd -<tab>' to see directory history conveniently.
 
         Usage:
 
           cd 'dir': changes to directory 'dir'.
 
           cd -: changes to the last visited directory.
 
           cd -<n>: changes to the n-th directory in the directory history.
 
           cd --foo: change to directory that matches 'foo' in history
             
           cd -b <bookmark_name>: jump to a bookmark set by %bookmark
              (note: cd <bookmark_name> is enough if there is no
               directory <bookmark_name>, but a bookmark with the name exists.)
               'cd -b <tab>' allows you to tab-complete bookmark names. 
 
         Options:
 
         -q: quiet.  Do not print the working directory after the cd command is
         executed.  By default IPython's cd command does print this directory,
         since the default prompts do not display path information.
         
         Note that !cd doesn't work for this purpose because the shell where
         !command runs is immediately discarded after executing 'command'."""
 
         parameter_s = parameter_s.strip()
         #bkms = self.shell.persist.get("bookmarks",{})
 
         oldcwd = os.getcwd()
         numcd = re.match(r'(-)(\d+)$',parameter_s)
         # jump in directory history by number
         if numcd:
             nn = int(numcd.group(2))
             try:
                 ps = self.shell.user_ns['_dh'][nn]
             except IndexError:
                 print 'The requested directory does not exist in history.'
                 return
             else:
                 opts = {}
         elif parameter_s.startswith('--'):
             ps = None
             fallback = None
             pat = parameter_s[2:]
             dh = self.shell.user_ns['_dh']
             # first search only by basename (last component)
             for ent in reversed(dh):
                 if pat in os.path.basename(ent) and os.path.isdir(ent):
                     ps = ent
                     break
             
                 if fallback is None and pat in ent and os.path.isdir(ent):
                     fallback = ent
                 
             # if we have no last part match, pick the first full path match
             if ps is None:
                 ps = fallback
             
             if ps is None:
                 print "No matching entry in directory history"
                 return
             else:
                 opts = {}
                 
             
         else:
             #turn all non-space-escaping backslashes to slashes, 
             # for c:\windows\directory\names\
             parameter_s = re.sub(r'\\(?! )','/', parameter_s)            
             opts,ps = self.parse_options(parameter_s,'qb',mode='string')
         # jump to previous
         if ps == '-':
             try:
                 ps = self.shell.user_ns['_dh'][-2]
             except IndexError:
                 raise UsageError('%cd -: No previous directory to change to.')
         # jump to bookmark if needed
         else:
             if not os.path.isdir(ps) or opts.has_key('b'):
                 bkms = self.db.get('bookmarks', {})
             
                 if bkms.has_key(ps):
                     target = bkms[ps]
                     print '(bookmark:%s) -> %s' % (ps,target)
                     ps = target
                 else:
                     if opts.has_key('b'):
                         raise UsageError("Bookmark '%s' not found.  "
                               "Use '%%bookmark -l' to see your bookmarks." % ps)
             
         # at this point ps should point to the target dir
         if ps:
             try:                
                 os.chdir(os.path.expanduser(ps))
                 if self.shell.rc.term_title:
                     #print 'set term title:',self.shell.rc.term_title  # dbg
                     platutils.set_term_title('IPy ' + abbrev_cwd())
             except OSError:
                 print sys.exc_info()[1]
             else:
                 cwd = os.getcwd()
                 dhist = self.shell.user_ns['_dh']
                 if oldcwd != cwd:
                     dhist.append(cwd)
                     self.db['dhist'] = compress_dhist(dhist)[-100:]
                 
         else:
             os.chdir(self.shell.home_dir)
             if self.shell.rc.term_title:
                 platutils.set_term_title("IPy ~")
             cwd = os.getcwd()
             dhist = self.shell.user_ns['_dh']
             
             if oldcwd != cwd:
                 dhist.append(cwd)
                 self.db['dhist'] = compress_dhist(dhist)[-100:]
         if not 'q' in opts and self.shell.user_ns['_dh']:
             print self.shell.user_ns['_dh'][-1]
 
 
     def magic_env(self, parameter_s=''):
         """List environment variables."""
         
         return os.environ.data
 
     def magic_pushd(self, parameter_s=''):
         """Place the current dir on stack and change directory.
         
         Usage:\\
           %pushd ['dirname']
         """
         
         dir_s = self.shell.dir_stack
         tgt = os.path.expanduser(parameter_s)
         cwd = os.getcwd().replace(self.home_dir,'~')
         if tgt:
             self.magic_cd(parameter_s)
         dir_s.insert(0,cwd)
         return self.magic_dirs()
 
     def magic_popd(self, parameter_s=''):
         """Change to directory popped off the top of the stack.
         """
         if not self.shell.dir_stack:
             raise UsageError("%popd on empty stack")
         top = self.shell.dir_stack.pop(0)
         self.magic_cd(top)
         print "popd ->",top
 
     def magic_dirs(self, parameter_s=''):
         """Return the current directory stack."""
 
         return self.shell.dir_stack
 
     def magic_dhist(self, parameter_s=''):
         """Print your history of visited directories.
 
         %dhist       -> print full history\\
         %dhist n     -> print last n entries only\\
         %dhist n1 n2 -> print entries between n1 and n2 (n1 not included)\\
 
         This history is automatically maintained by the %cd command, and
         always available as the global list variable _dh. You can use %cd -<n>
         to go to directory number <n>.
         
         Note that most of time, you should view directory history by entering
         cd -<TAB>.
         
         """
 
         dh = self.shell.user_ns['_dh']
         if parameter_s:
             try:
                 args = map(int,parameter_s.split())
             except:
                 self.arg_err(Magic.magic_dhist)
                 return
             if len(args) == 1:
                 ini,fin = max(len(dh)-(args[0]),0),len(dh)
             elif len(args) == 2:
                 ini,fin = args
             else:
                 self.arg_err(Magic.magic_dhist)
                 return
         else:
             ini,fin = 0,len(dh)
         nlprint(dh,
                 header = 'Directory history (kept in _dh)',
                 start=ini,stop=fin)
 
     @testdec.skip_doctest
     def magic_sc(self, parameter_s=''):
         """Shell capture - execute a shell command and capture its output.
 
         DEPRECATED. Suboptimal, retained for backwards compatibility.
         
         You should use the form 'var = !command' instead. Example:
          
          "%sc -l myfiles = ls ~" should now be written as
             
          "myfiles = !ls ~"
          
         myfiles.s, myfiles.l and myfiles.n still apply as documented
         below.
 
         --
         %sc [options] varname=command
 
         IPython will run the given command using commands.getoutput(), and
         will then update the user's interactive namespace with a variable
         called varname, containing the value of the call.  Your command can
         contain shell wildcards, pipes, etc.
 
         The '=' sign in the syntax is mandatory, and the variable name you
         supply must follow Python's standard conventions for valid names.
         
         (A special format without variable name exists for internal use)
 
         Options:
 
           -l: list output.  Split the output on newlines into a list before
           assigning it to the given variable.  By default the output is stored
           as a single string.
 
           -v: verbose.  Print the contents of the variable.
 
         In most cases you should not need to split as a list, because the
         returned value is a special type of string which can automatically
         provide its contents either as a list (split on newlines) or as a
         space-separated string.  These are convenient, respectively, either
         for sequential processing or to be passed to a shell command.
 
         For example:
 
         # all-random
         
             # Capture into variable a
             In [1]: sc a=ls *py
 
             # a is a string with embedded newlines
             In [2]: a
             Out[2]: 'setup.py\\nwin32_manual_post_install.py'
 
             # which can be seen as a list:
             In [3]: a.l
             Out[3]: ['setup.py', 'win32_manual_post_install.py']
 
             # or as a whitespace-separated string:
             In [4]: a.s
             Out[4]: 'setup.py win32_manual_post_install.py'
 
             # a.s is useful to pass as a single command line:
             In [5]: !wc -l $a.s
               146 setup.py
               130 win32_manual_post_install.py
               276 total
 
             # while the list form is useful to loop over:
             In [6]: for f in a.l:
               ...:      !wc -l $f
               ...:
             146 setup.py
             130 win32_manual_post_install.py
 
         Similiarly, the lists returned by the -l option are also special, in
         the sense that you can equally invoke the .s attribute on them to
         automatically get a whitespace-separated string from their contents:
 
             In [7]: sc -l b=ls *py
 
             In [8]: b
             Out[8]: ['setup.py', 'win32_manual_post_install.py']
 
             In [9]: b.s
             Out[9]: 'setup.py win32_manual_post_install.py'
 
         In summary, both the lists and strings used for ouptut capture have
         the following special attributes:
 
             .l (or .list) : value as list.
             .n (or .nlstr): value as newline-separated string.
             .s (or .spstr): value as space-separated string.
         """
 
         opts,args = self.parse_options(parameter_s,'lv')
         # Try to get a variable name and command to run
         try:
             # the variable name must be obtained from the parse_options
             # output, which uses shlex.split to strip options out.
             var,_ = args.split('=',1)
             var = var.strip()
             # But the the command has to be extracted from the original input
             # parameter_s, not on what parse_options returns, to avoid the
             # quote stripping which shlex.split performs on it.
             _,cmd = parameter_s.split('=',1)
         except ValueError:
             var,cmd = '',''
         # If all looks ok, proceed
         out,err = self.shell.getoutputerror(cmd)
         if err:
             print >> Term.cerr,err
         if opts.has_key('l'):
             out = SList(out.split('\n'))
         else:
             out = LSString(out)
         if opts.has_key('v'):
             print '%s ==\n%s' % (var,pformat(out))
         if var:
             self.shell.user_ns.update({var:out})
         else:
             return out
 
     def magic_sx(self, parameter_s=''):
         """Shell execute - run a shell command and capture its output.
 
         %sx command
 
         IPython will run the given command using commands.getoutput(), and
         return the result formatted as a list (split on '\\n').  Since the
         output is _returned_, it will be stored in ipython's regular output
         cache Out[N] and in the '_N' automatic variables.
 
         Notes:
 
         1) If an input line begins with '!!', then %sx is automatically
         invoked.  That is, while:
           !ls
         causes ipython to simply issue system('ls'), typing
           !!ls
         is a shorthand equivalent to:
           %sx ls
         
         2) %sx differs from %sc in that %sx automatically splits into a list,
         like '%sc -l'.  The reason for this is to make it as easy as possible
         to process line-oriented shell output via further python commands.
         %sc is meant to provide much finer control, but requires more
         typing.
 
         3) Just like %sc -l, this is a list with special attributes:
 
           .l (or .list) : value as list.
           .n (or .nlstr): value as newline-separated string.
           .s (or .spstr): value as whitespace-separated string.
 
         This is very useful when trying to use such lists as arguments to
         system commands."""
 
         if parameter_s:
             out,err = self.shell.getoutputerror(parameter_s)
             if err:
                 print >> Term.cerr,err
             return SList(out.split('\n'))
 
     def magic_bg(self, parameter_s=''):
         """Run a job in the background, in a separate thread.
 
         For example,
 
           %bg myfunc(x,y,z=1)
 
         will execute 'myfunc(x,y,z=1)' in a background thread.  As soon as the
         execution starts, a message will be printed indicating the job
         number.  If your job number is 5, you can use
 
           myvar = jobs.result(5)  or  myvar = jobs[5].result
 
         to assign this result to variable 'myvar'.
 
         IPython has a job manager, accessible via the 'jobs' object.  You can
         type jobs? to get more information about it, and use jobs.<TAB> to see
         its attributes.  All attributes not starting with an underscore are
         meant for public use.
 
         In particular, look at the jobs.new() method, which is used to create
         new jobs.  This magic %bg function is just a convenience wrapper
         around jobs.new(), for expression-based jobs.  If you want to create a
         new job with an explicit function object and arguments, you must call
         jobs.new() directly.
 
         The jobs.new docstring also describes in detail several important
         caveats associated with a thread-based model for background job
         execution.  Type jobs.new? for details.
 
         You can check the status of all jobs with jobs.status().
 
         The jobs variable is set by IPython into the Python builtin namespace.
         If you ever declare a variable named 'jobs', you will shadow this
         name.  You can either delete your global jobs variable to regain
         access to the job manager, or make a new name and assign it manually
         to the manager (stored in IPython's namespace).  For example, to
         assign the job manager to the Jobs name, use:
 
           Jobs = __builtins__.jobs"""
         
         self.shell.jobs.new(parameter_s,self.shell.user_ns)
         
     def magic_r(self, parameter_s=''):
         """Repeat previous input.
 
         Note: Consider using the more powerfull %rep instead!
         
         If given an argument, repeats the previous command which starts with
         the same string, otherwise it just repeats the previous input.
 
         Shell escaped commands (with ! as first character) are not recognized
         by this system, only pure python code and magic commands.
         """
 
         start = parameter_s.strip()
         esc_magic = self.shell.ESC_MAGIC
         # Identify magic commands even if automagic is on (which means
         # the in-memory version is different from that typed by the user).
         if self.shell.rc.automagic:
             start_magic = esc_magic+start
         else:
             start_magic = start
         # Look through the input history in reverse
         for n in range(len(self.shell.input_hist)-2,0,-1):
             input = self.shell.input_hist[n]
             # skip plain 'r' lines so we don't recurse to infinity
             if input != '_ip.magic("r")\n' and \
                    (input.startswith(start) or input.startswith(start_magic)):
                 #print 'match',`input`  # dbg
                 print 'Executing:',input,
                 self.shell.runlines(input)
                 return
         print 'No previous input matching `%s` found.' % start
 
     
     def magic_bookmark(self, parameter_s=''):
         """Manage IPython's bookmark system.
 
         %bookmark <name>       - set bookmark to current dir
         %bookmark <name> <dir> - set bookmark to <dir>
         %bookmark -l           - list all bookmarks
         %bookmark -d <name>    - remove bookmark
         %bookmark -r           - remove all bookmarks
 
         You can later on access a bookmarked folder with:
           %cd -b <name>
         or simply '%cd <name>' if there is no directory called <name> AND
         there is such a bookmark defined.
 
         Your bookmarks persist through IPython sessions, but they are
         associated with each profile."""
 
         opts,args = self.parse_options(parameter_s,'drl',mode='list')
         if len(args) > 2:
             raise UsageError("%bookmark: too many arguments")
 
         bkms = self.db.get('bookmarks',{})
             
         if opts.has_key('d'):
             try:
                 todel = args[0]
             except IndexError:
                 raise UsageError(
                     "%bookmark -d: must provide a bookmark to delete")
             else:
                 try:
                     del bkms[todel]
                 except KeyError:
                     raise UsageError(
                         "%%bookmark -d: Can't delete bookmark '%s'" % todel)
 
         elif opts.has_key('r'):
             bkms = {}
         elif opts.has_key('l'):
             bks = bkms.keys()
             bks.sort()
             if bks:
                 size = max(map(len,bks))
             else:
                 size = 0
             fmt = '%-'+str(size)+'s -> %s'
             print 'Current bookmarks:'
             for bk in bks:
                 print fmt % (bk,bkms[bk])
         else:
             if not args:
                 raise UsageError("%bookmark: You must specify the bookmark name")
             elif len(args)==1:
                 bkms[args[0]] = os.getcwd()
             elif len(args)==2:
                 bkms[args[0]] = args[1]
         self.db['bookmarks'] = bkms
 
     def magic_pycat(self, parameter_s=''):
         """Show a syntax-highlighted file through a pager.
 
         This magic is similar to the cat utility, but it will assume the file
         to be Python source and will show it with syntax highlighting. """
         
         try:
             filename = get_py_filename(parameter_s)
             cont = file_read(filename)
         except IOError:
             try:
                 cont = eval(parameter_s,self.user_ns)
             except NameError:
                 cont = None
         if cont is None:
             print "Error: no such file or variable"
             return
             
         page(self.shell.pycolorize(cont),
              screen_lines=self.shell.rc.screen_length)
 
     def magic_cpaste(self, parameter_s=''):
         """Allows you to paste & execute a pre-formatted code block from clipboard.
         
         You must terminate the block with '--' (two minus-signs) alone on the
         line. You can also provide your own sentinel with '%paste -s %%' ('%%' 
         is the new sentinel for this operation)
         
         The block is dedented prior to execution to enable execution of method
         definitions. '>' and '+' characters at the beginning of a line are
         ignored, to allow pasting directly from e-mails, diff files and
         doctests (the '...' continuation prompt is also stripped).  The
         executed block is also assigned to variable named 'pasted_block' for
         later editing with '%edit pasted_block'.
         
         You can also pass a variable name as an argument, e.g. '%cpaste foo'.
         This assigns the pasted block to variable 'foo' as string, without 
         dedenting or executing it (preceding >>> and + is still stripped)
         
         '%cpaste -r' re-executes the block previously entered by cpaste.
         
         Do not be alarmed by garbled output on Windows (it's a readline bug). 
         Just press enter and type -- (and press enter again) and the block 
         will be what was just pasted.
         
         IPython statements (magics, shell escapes) are not supported (yet).
         """
         opts,args = self.parse_options(parameter_s,'rs:',mode='string')
         par = args.strip()
         if opts.has_key('r'):
             b = self.user_ns.get('pasted_block', None)
             if b is None:
                 raise UsageError('No previous pasted block available')
             print "Re-executing '%s...' (%d chars)"% (b.split('\n',1)[0], len(b))
             exec b in self.user_ns
             return
         
         sentinel = opts.get('s','--')
 
         # Regular expressions that declare text we strip from the input:
         strip_re =  [r'^\s*In \[\d+\]:', # IPython input prompt
                      r'^\s*(\s?>)+', # Python input prompt
                      r'^\s*\.{3,}', # Continuation prompts
                      r'^\++',
                      ]
 
         strip_from_start = map(re.compile,strip_re)
         
         from IPython import iplib
         lines = []
         print "Pasting code; enter '%s' alone on the line to stop." % sentinel
         while 1:
             l = iplib.raw_input_original(':')
             if l ==sentinel:
                 break
             
             for pat in strip_from_start: 
                 l = pat.sub('',l)
             lines.append(l)
                          
         block = "\n".join(lines) + '\n'
         #print "block:\n",block
         if not par:
             b = textwrap.dedent(block)
             self.user_ns['pasted_block'] = b
             exec b in self.user_ns
         else:
             self.user_ns[par] = SList(block.splitlines())
             print "Block assigned to '%s'" % par
             
     def magic_quickref(self,arg):
         """ Show a quick reference sheet """
         import IPython.usage
         qr = IPython.usage.quick_reference + self.magic_magic('-brief')
         
         page(qr)
         
     def magic_upgrade(self,arg):
         """ Upgrade your IPython installation
         
         This will copy the config files that don't yet exist in your 
         ipython dir from the system config dir. Use this after upgrading 
         IPython if you don't wish to delete your .ipython dir.
 
         Call with -nolegacy to get rid of ipythonrc* files (recommended for
         new users)
 
         """
         ip = self.getapi()
         ipinstallation = path(IPython.__file__).dirname()
         upgrade_script = '%s "%s"' % (sys.executable,ipinstallation / 'upgrade_dir.py')
         src_config = ipinstallation / 'UserConfig'
         userdir = path(ip.options.ipythondir)
         cmd = '%s "%s" "%s"' % (upgrade_script, src_config, userdir)
         print ">",cmd
         shell(cmd)
         if arg == '-nolegacy':
             legacy = userdir.files('ipythonrc*')
             print "Nuking legacy files:",legacy
             
             [p.remove() for p in legacy]
             suffix = (sys.platform == 'win32' and '.ini' or '')
             (userdir / ('ipythonrc' + suffix)).write_text('# Empty, see ipy_user_conf.py\n')
 
 
     def magic_doctest_mode(self,parameter_s=''):
         """Toggle doctest mode on and off.
 
         This mode allows you to toggle the prompt behavior between normal
         IPython prompts and ones that are as similar to the default IPython
         interpreter as possible.
 
         It also supports the pasting of code snippets that have leading '>>>'
         and '...' prompts in them.  This means that you can paste doctests from
         files or docstrings (even if they have leading whitespace), and the
         code will execute correctly.  You can then use '%history -tn' to see
         the translated history without line numbers; this will give you the
         input after removal of all the leading prompts and whitespace, which
         can be pasted back into an editor.
 
         With these features, you can switch into this mode easily whenever you
         need to do testing and changes to doctests, without having to leave
         your existing IPython session.
         """
 
         # XXX - Fix this to have cleaner activate/deactivate calls.
         from IPython.Extensions import InterpreterPasteInput as ipaste
         from IPython.ipstruct import Struct
 
         # Shorthands
         shell = self.shell
         oc = shell.outputcache
         rc = shell.rc
         meta = shell.meta
         # dstore is a data store kept in the instance metadata bag to track any
         # changes we make, so we can undo them later.
         dstore = meta.setdefault('doctest_mode',Struct())
         save_dstore = dstore.setdefault
 
         # save a few values we'll need to recover later
         mode = save_dstore('mode',False)
         save_dstore('rc_pprint',rc.pprint)
         save_dstore('xmode',shell.InteractiveTB.mode)
         save_dstore('rc_separate_out',rc.separate_out)
         save_dstore('rc_separate_out2',rc.separate_out2)
         save_dstore('rc_prompts_pad_left',rc.prompts_pad_left)
         save_dstore('rc_separate_in',rc.separate_in)
 
         if mode == False:
             # turn on
             ipaste.activate_prefilter()
 
             oc.prompt1.p_template = '>>> '
             oc.prompt2.p_template = '... '
             oc.prompt_out.p_template = ''
 
             # Prompt separators like plain python
             oc.input_sep = oc.prompt1.sep = ''
             oc.output_sep = ''
             oc.output_sep2 = ''
 
             oc.prompt1.pad_left = oc.prompt2.pad_left = \
                                   oc.prompt_out.pad_left = False
 
             rc.pprint = False
 
             shell.magic_xmode('Plain')
 
         else:
             # turn off
             ipaste.deactivate_prefilter()
 
             oc.prompt1.p_template = rc.prompt_in1
             oc.prompt2.p_template = rc.prompt_in2
             oc.prompt_out.p_template = rc.prompt_out
 
             oc.input_sep = oc.prompt1.sep = dstore.rc_separate_in
 
             oc.output_sep = dstore.rc_separate_out
             oc.output_sep2 = dstore.rc_separate_out2
 
             oc.prompt1.pad_left = oc.prompt2.pad_left = \
                          oc.prompt_out.pad_left = dstore.rc_prompts_pad_left
 
             rc.pprint = dstore.rc_pprint
 
             shell.magic_xmode(dstore.xmode)
 
         # Store new mode and inform
         dstore.mode = bool(1-int(mode))
         print 'Doctest mode is:',
         print ['OFF','ON'][dstore.mode]
 
 # end Magic

IPython/iplib.py

@@ -1,2839 +1,2865 b''
 # -*- coding: utf-8 -*-
 """
 IPython -- An enhanced Interactive Python
 
 Requires Python 2.4 or newer.
 
 This file contains all the classes and helper functions specific to IPython.
 """
 
 #*****************************************************************************
 #       Copyright (C) 2001 Janko Hauser <[e-mail]> and
 #       Copyright (C) 2001-2006 Fernando Perez. <[e-mail]>
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #
 # Note: this code originally subclassed code.InteractiveConsole from the
 # Python standard library.  Over time, all of that class has been copied
 # verbatim here for modifications which could not be accomplished by
 # subclassing.  At this point, there are no dependencies at all on the code
 # module anymore (it is not even imported).  The Python License (sec. 2)
 # allows for this, but it's always nice to acknowledge credit where credit is
 # due.
 #*****************************************************************************
 
 #****************************************************************************
 # Modules and globals
 
 # Python standard modules
 import __main__
 import __builtin__
 import StringIO
 import bdb
 import cPickle as pickle
 import codeop
 import exceptions
 import glob
 import inspect
 import keyword
 import new
 import os
 import pydoc
 import re
 import shutil
 import string
 import sys
 import tempfile
 import traceback
 import types
 from pprint import pprint, pformat
 
 # IPython's own modules
 #import IPython
 from IPython import Debugger,OInspect,PyColorize,ultraTB
 from IPython.ColorANSI import ColorScheme,ColorSchemeTable  # too long names
 from IPython.Extensions import pickleshare
-from IPython.FakeModule import FakeModule
+from IPython.FakeModule import FakeModule, init_fakemod_dict
 from IPython.Itpl import Itpl,itpl,printpl,ItplNS,itplns
 from IPython.Logger import Logger
 from IPython.Magic import Magic
 from IPython.Prompts import CachedOutput
 from IPython.ipstruct import Struct
 from IPython.background_jobs import BackgroundJobManager
 from IPython.usage import cmd_line_usage,interactive_usage
 from IPython.genutils import *
 from IPython.strdispatch import StrDispatch
 import IPython.ipapi
 import IPython.history
 import IPython.prefilter as prefilter
 import IPython.shadowns
 # Globals
 
 # store the builtin raw_input globally, and use this always, in case user code
 # overwrites it (like wx.py.PyShell does)
 raw_input_original = raw_input
 
 # compiled regexps for autoindent management
 dedent_re = re.compile(r'^\s+raise|^\s+return|^\s+pass')
 
 
 #****************************************************************************
 # Some utility function definitions
 
 ini_spaces_re = re.compile(r'^(\s+)')
 
 def num_ini_spaces(strng):
     """Return the number of initial spaces in a string"""
 
     ini_spaces = ini_spaces_re.match(strng)
     if ini_spaces:
         return ini_spaces.end()
     else:
         return 0
 
 def softspace(file, newvalue):
     """Copied from code.py, to remove the dependency"""
 
     oldvalue = 0
     try:
         oldvalue = file.softspace
     except AttributeError:
         pass
     try:
         file.softspace = newvalue
     except (AttributeError, TypeError):
         # "attribute-less object" or "read-only attributes"
         pass
     return oldvalue
 
 
 def user_setup(ipythondir,rc_suffix,mode='install',interactive=True):
     """Install or upgrade the user configuration directory.
 
     Can be called when running for the first time or to upgrade the user's
     .ipython/ directory.
 
     Parameters
     ----------
       ipythondir : path
         The directory to be used for installation/upgrade.  In 'install' mode,
         if this path already exists, the function exits immediately.
 
       rc_suffix : str
         Extension for the config files.  On *nix platforms it is typically the
         empty string, while Windows normally uses '.ini'.
 
       mode : str, optional
         Valid modes are 'install' and 'upgrade'.
 
       interactive : bool, optional
         If False, do not wait for user input on any errors.  Normally after
         printing its status information, this function waits for the user to
         hit Return before proceeding.  This is because the default use case is
         when first installing the IPython configuration, so we want the user to
         acknowledge the initial message, which contains some useful
         information.
         """
 
     # For automatic use, deactivate all i/o
     if interactive:
         def wait():
             try:
                 raw_input("Please press <RETURN> to start IPython.")
             except EOFError:
                 print >> Term.cout
             print '*'*70
 
         def printf(s):
             print s
     else:
         wait = lambda : None
         printf = lambda s : None
 
     # Install mode should be re-entrant: if the install dir already exists,
     # bail out cleanly
     if mode == 'install' and os.path.isdir(ipythondir):
         return
 
     cwd = os.getcwd()  # remember where we started
     glb = glob.glob
 
     printf('*'*70)
     if mode == 'install':
         printf(
 """Welcome to IPython. I will try to create a personal configuration directory
 where you can customize many aspects of IPython's functionality in:\n""")
     else:
         printf('I am going to upgrade your configuration in:')
 
     printf(ipythondir)
 
     rcdirend = os.path.join('IPython','UserConfig')
     cfg = lambda d: os.path.join(d,rcdirend)
     try:
         rcdir = filter(os.path.isdir,map(cfg,sys.path))[0]
         printf("Initializing from configuration: %s" % rcdir)
     except IndexError:
         warning = """
 Installation error. IPython's directory was not found.
 
 Check the following:
 
 The ipython/IPython directory should be in a directory belonging to your
 PYTHONPATH environment variable (that is, it should be in a directory
 belonging to sys.path). You can copy it explicitly there or just link to it.
 
 IPython will create a minimal default configuration for you.
 
 """
         warn(warning)
         wait()
 
         if sys.platform =='win32':
             inif = 'ipythonrc.ini'
         else:
             inif = 'ipythonrc'
         minimal_setup = {'ipy_user_conf.py' : 'import ipy_defaults',
                          inif : '# intentionally left blank' }
         os.makedirs(ipythondir, mode = 0777)
         for f, cont in minimal_setup.items():
             # In 2.5, this can be more cleanly done using 'with'
             fobj = file(ipythondir + '/' + f,'w')
             fobj.write(cont)
             fobj.close()
 
         return
 
     if mode == 'install':
         try:
             shutil.copytree(rcdir,ipythondir)
             os.chdir(ipythondir)
             rc_files = glb("ipythonrc*")
             for rc_file in rc_files:
                 os.rename(rc_file,rc_file+rc_suffix)
         except:
             warning = """
 
 There was a problem with the installation:
 %s
 Try to correct it or contact the developers if you think it's a bug.
 IPython will proceed with builtin defaults.""" % sys.exc_info()[1]
             warn(warning)
             wait()
             return
 
     elif mode == 'upgrade':
         try:
             os.chdir(ipythondir)
         except:
             printf("""
 Can not upgrade: changing to directory %s failed. Details:
 %s
 """ % (ipythondir,sys.exc_info()[1]) )
             wait()
             return
         else:
             sources = glb(os.path.join(rcdir,'[A-Za-z]*'))
             for new_full_path in sources:
                 new_filename = os.path.basename(new_full_path)
                 if new_filename.startswith('ipythonrc'):
                     new_filename = new_filename + rc_suffix
                 # The config directory should only contain files, skip any
                 # directories which may be there (like CVS)
                 if os.path.isdir(new_full_path):
                     continue
                 if os.path.exists(new_filename):
                     old_file = new_filename+'.old'
                     if os.path.exists(old_file):
                         os.remove(old_file)
                     os.rename(new_filename,old_file)
                 shutil.copy(new_full_path,new_filename)
     else:
         raise ValueError('unrecognized mode for install: %r' % mode)
 
     # Fix line-endings to those native to each platform in the config
     # directory.
     try:
         os.chdir(ipythondir)
     except:
         printf("""
 Problem: changing to directory %s failed.
 Details:
 %s
 
 Some configuration files may have incorrect line endings.  This should not
 cause any problems during execution.  """ % (ipythondir,sys.exc_info()[1]) )
         wait()
     else:
         for fname in glb('ipythonrc*'):
             try:
                 native_line_ends(fname,backup=0)
             except IOError:
                 pass
 
     if mode == 'install':
         printf("""
 Successful installation!
 
 Please read the sections 'Initial Configuration' and 'Quick Tips' in the
 IPython manual (there are both HTML and PDF versions supplied with the
 distribution) to make sure that your system environment is properly configured
 to take advantage of IPython's features.
 
 Important note: the configuration system has changed! The old system is
 still in place, but its setting may be partly overridden by the settings in 
 "~/.ipython/ipy_user_conf.py" config file. Please take a look at the file 
 if some of the new settings bother you. 
 
 """)
     else:
         printf("""
 Successful upgrade!
 
 All files in your directory:
 %(ipythondir)s
 which would have been overwritten by the upgrade were backed up with a .old
 extension.  If you had made particular customizations in those files you may
 want to merge them back into the new files.""" % locals() )
     wait()
     os.chdir(cwd)
 
 #****************************************************************************
 # Local use exceptions
 class SpaceInInput(exceptions.Exception): pass
 
 
 #****************************************************************************
 # Local use classes
 class Bunch: pass
 
 class Undefined: pass
 
 class Quitter(object):
     """Simple class to handle exit, similar to Python 2.5's.
 
     It handles exiting in an ipython-safe manner, which the one in Python 2.5
     doesn't do (obviously, since it doesn't know about ipython)."""
     
     def __init__(self,shell,name):
         self.shell = shell
         self.name = name
         
     def __repr__(self):
         return 'Type %s() to exit.' % self.name
     __str__ = __repr__
 
     def __call__(self):
         self.shell.exit()
 
 class InputList(list):
     """Class to store user input.
 
     It's basically a list, but slices return a string instead of a list, thus
     allowing things like (assuming 'In' is an instance):
 
     exec In[4:7]
 
     or
 
     exec In[5:9] + In[14] + In[21:25]"""
 
     def __getslice__(self,i,j):
         return ''.join(list.__getslice__(self,i,j))
 
 class SyntaxTB(ultraTB.ListTB):
     """Extension which holds some state: the last exception value"""
 
     def __init__(self,color_scheme = 'NoColor'):
         ultraTB.ListTB.__init__(self,color_scheme)
         self.last_syntax_error = None
 
     def __call__(self, etype, value, elist):
         self.last_syntax_error = value
         ultraTB.ListTB.__call__(self,etype,value,elist)
 
     def clear_err_state(self):
         """Return the current error state and clear it"""
         e = self.last_syntax_error
         self.last_syntax_error = None
         return e
 
 #****************************************************************************
 # Main IPython class
 
 # FIXME: the Magic class is a mixin for now, and will unfortunately remain so
 # until a full rewrite is made.  I've cleaned all cross-class uses of
 # attributes and methods, but too much user code out there relies on the
 # equlity %foo == __IP.magic_foo, so I can't actually remove the mixin usage.
 #
 # But at least now, all the pieces have been separated and we could, in
 # principle, stop using the mixin.  This will ease the transition to the
 # chainsaw branch.
 
 # For reference, the following is the list of 'self.foo' uses in the Magic
 # class as of 2005-12-28.  These are names we CAN'T use in the main ipython
 # class, to prevent clashes.
 
 # ['self.__class__', 'self.__dict__', 'self._inspect', 'self._ofind',
 #  'self.arg_err', 'self.extract_input', 'self.format_', 'self.lsmagic',
 #  'self.magic_', 'self.options_table', 'self.parse', 'self.shell',
 #  'self.value']
 
 class InteractiveShell(object,Magic):
     """An enhanced console for Python."""
 
     # class attribute to indicate whether the class supports threads or not.
     # Subclasses with thread support should override this as needed.
     isthreaded = False
 
     def __init__(self,name,usage=None,rc=Struct(opts=None,args=None),
                  user_ns=None,user_global_ns=None,banner2='',
                  custom_exceptions=((),None),embedded=False):
 
         # log system
         self.logger = Logger(self,logfname='ipython_log.py',logmode='rotate')
             
         # Job manager (for jobs run as background threads)
         self.jobs = BackgroundJobManager()
 
         # Store the actual shell's name
         self.name = name
         self.more = False
 
         # We need to know whether the instance is meant for embedding, since
         # global/local namespaces need to be handled differently in that case
         self.embedded = embedded
         if embedded:
             # Control variable so users can, from within the embedded instance,
             # permanently deactivate it.
             self.embedded_active = True
 
         # command compiler
         self.compile = codeop.CommandCompiler()
 
         # User input buffer
         self.buffer = []
 
         # Default name given in compilation of code
         self.filename = '<ipython console>'
 
         # Install our own quitter instead of the builtins.  For python2.3-2.4,
         # this brings in behavior like 2.5, and for 2.5 it's identical.
         __builtin__.exit = Quitter(self,'exit')
         __builtin__.quit = Quitter(self,'quit')
         
         # Make an empty namespace, which extension writers can rely on both
         # existing and NEVER being used by ipython itself.  This gives them a
         # convenient location for storing additional information and state
         # their extensions may require, without fear of collisions with other
         # ipython names that may develop later.
         self.meta = Struct()
 
         # Create the namespace where the user will operate.  user_ns is
         # normally the only one used, and it is passed to the exec calls as
         # the locals argument.  But we do carry a user_global_ns namespace
         # given as the exec 'globals' argument,  This is useful in embedding
         # situations where the ipython shell opens in a context where the
         # distinction between locals and globals is meaningful.  For
         # non-embedded contexts, it is just the same object as the user_ns dict.
 
         # FIXME. For some strange reason, __builtins__ is showing up at user
         # level as a dict instead of a module. This is a manual fix, but I
         # should really track down where the problem is coming from. Alex
         # Schmolck reported this problem first.
 
         # A useful post by Alex Martelli on this topic:
         # Re: inconsistent value from __builtins__
         # Von: Alex Martelli <[e-mail]>
         # Datum: Freitag 01 Oktober 2004 04:45:34 nachmittags/abends
         # Gruppen: comp.lang.python
 
         # Michael Hohn <[e-mail]> wrote:
         # > >>> print type(builtin_check.get_global_binding('__builtins__'))
         # > <type 'dict'>
         # > >>> print type(__builtins__)
         # > <type 'module'>
         # > Is this difference in return value intentional?
 
         # Well, it's documented that '__builtins__' can be either a dictionary
         # or a module, and it's been that way for a long time. Whether it's
         # intentional (or sensible), I don't know. In any case, the idea is
         # that if you need to access the built-in namespace directly, you
         # should start with "import __builtin__" (note, no 's') which will
         # definitely give you a module. Yeah, it's somewhat confusing:-(.
 
         # These routines return properly built dicts as needed by the rest of
         # the code, and can also be used by extension writers to generate
         # properly initialized namespaces.
         user_ns, user_global_ns = IPython.ipapi.make_user_namespaces(user_ns,
             user_global_ns)
 
         # Assign namespaces
         # This is the namespace where all normal user variables live
         self.user_ns = user_ns
         self.user_global_ns = user_global_ns
 
         # An auxiliary namespace that checks what parts of the user_ns were
         # loaded at startup, so we can list later only variables defined in
         # actual interactive use.  Since it is always a subset of user_ns, it
         # doesn't need to be seaparately tracked in the ns_table
         self.user_config_ns = {}
 
         # A namespace to keep track of internal data structures to prevent
         # them from cluttering user-visible stuff.  Will be updated later
         self.internal_ns = {}
 
         # Namespace of system aliases.  Each entry in the alias
         # table must be a 2-tuple of the form (N,name), where N is the number
         # of positional arguments of the alias.
         self.alias_table = {}
 
         # Now that FakeModule produces a real module, we've run into a nasty
         # problem: after script execution (via %run), the module where the user
         # code ran is deleted.  Now that this object is a true module (needed
         # so docetst and other tools work correctly), the Python module
         # teardown mechanism runs over it, and sets to None every variable
         # present in that module.  Top-level references to objects from the
         # script survive, because the user_ns is updated with them.  However,
         # calling functions defined in the script that use other things from
         # the script will fail, because the function's closure had references
         # to the original objects, which are now all None.  So we must protect
-        # these modules from deletion by keeping a cache.  To avoid keeping
-        # stale modules around (we only need the one from the last run), we use
-        # a dict keyed with the full path to the script, so only the last
-        # version of the module is held in the cache.  The %reset command will
-        # flush this cache.  See the cache_main_mod() and clear_main_mod_cache()
-        # methods for details on use.
-        self._user_main_modules = {}
+        # these modules from deletion by keeping a cache.
+        # 
+        # To avoid keeping stale modules around (we only need the one from the
+        # last run), we use a dict keyed with the full path to the script, so
+        # only the last version of the module is held in the cache.  Note,
+        # however, that we must cache the module *namespace contents* (their
+        # __dict__).  Because if we try to cache the actual modules, old ones
+        # (uncached) could be destroyed while still holding references (such as
+        # those held by GUI objects that tend to be long-lived)>
+        # 
+        # The %reset command will flush this cache.  See the cache_main_mod()
+        # and clear_main_mod_cache() methods for details on use.
+
+        # This is the cache used for 'main' namespaces
+        self._main_ns_cache = {}
+        # And this is the single instance of FakeModule whose __dict__ we keep
+        # copying and clearing for reuse on each %run
+        self._user_main_module = FakeModule()
 
         # A table holding all the namespaces IPython deals with, so that
         # introspection facilities can search easily.
         self.ns_table = {'user':user_ns,
                          'user_global':user_global_ns,
                          'alias':self.alias_table,
                          'internal':self.internal_ns,
                          'builtin':__builtin__.__dict__
                          }
 
         # Similarly, track all namespaces where references can be held and that
         # we can safely clear (so it can NOT include builtin).  This one can be
         # a simple list.
         self.ns_refs_table = [ user_ns, user_global_ns, self.user_config_ns,
                                self.alias_table, self.internal_ns,
-                               self._user_main_modules ]
+                               self._main_ns_cache ]
         
         # We need to insert into sys.modules something that looks like a
         # module but which accesses the IPython namespace, for shelve and
         # pickle to work interactively. Normally they rely on getting
         # everything out of __main__, but for embedding purposes each IPython
         # instance has its own private namespace, so we can't go shoving
         # everything into __main__.
 
         # note, however, that we should only do this for non-embedded
         # ipythons, which really mimic the __main__.__dict__ with their own
         # namespace.  Embedded instances, on the other hand, should not do
         # this because they need to manage the user local/global namespaces
         # only, but they live within a 'normal' __main__ (meaning, they
         # shouldn't overtake the execution environment of the script they're
         # embedded in).
 
         if not embedded:
             try:
                 main_name = self.user_ns['__name__']
             except KeyError:
                 raise KeyError,'user_ns dictionary MUST have a "__name__" key'
             else:
                 #print "pickle hack in place"  # dbg
                 #print 'main_name:',main_name # dbg
                 sys.modules[main_name] = FakeModule(self.user_ns)
         
         # List of input with multi-line handling.
         self.input_hist = InputList()
         # This one will hold the 'raw' input history, without any
         # pre-processing.  This will allow users to retrieve the input just as
         # it was exactly typed in by the user, with %hist -r.
         self.input_hist_raw = InputList()
 
         # list of visited directories
         try:
             self.dir_hist = [os.getcwd()]
         except OSError:
             self.dir_hist = []
 
         # dict of output history
         self.output_hist = {}
 
         # Get system encoding at startup time.  Certain terminals (like Emacs
         # under Win32 have it set to None, and we need to have a known valid
         # encoding to use in the raw_input() method
         try:
             self.stdin_encoding = sys.stdin.encoding or 'ascii'
         except AttributeError:
             self.stdin_encoding = 'ascii'
 
         # dict of things NOT to alias (keywords, builtins and some magics)
         no_alias = {}
         no_alias_magics = ['cd','popd','pushd','dhist','alias','unalias']
         for key in keyword.kwlist + no_alias_magics:
             no_alias[key] = 1
         no_alias.update(__builtin__.__dict__)
         self.no_alias = no_alias
 
         # Object variable to store code object waiting execution.  This is
         # used mainly by the multithreaded shells, but it can come in handy in
         # other situations.  No need to use a Queue here, since it's a single
         # item which gets cleared once run.
         self.code_to_run = None
         
         # escapes for automatic behavior on the command line
         self.ESC_SHELL  = '!'
         self.ESC_SH_CAP = '!!'
         self.ESC_HELP   = '?'
         self.ESC_MAGIC  = '%'
         self.ESC_QUOTE  = ','
         self.ESC_QUOTE2 = ';'
         self.ESC_PAREN  = '/'
 
         # And their associated handlers
         self.esc_handlers = {self.ESC_PAREN  : self.handle_auto,
                              self.ESC_QUOTE  : self.handle_auto,
                              self.ESC_QUOTE2 : self.handle_auto,
                              self.ESC_MAGIC  : self.handle_magic,
                              self.ESC_HELP   : self.handle_help,
                              self.ESC_SHELL  : self.handle_shell_escape,
                              self.ESC_SH_CAP : self.handle_shell_escape,
                              }
 
         # class initializations
         Magic.__init__(self,self)
 
         # Python source parser/formatter for syntax highlighting
         pyformat = PyColorize.Parser().format
         self.pycolorize = lambda src: pyformat(src,'str',self.rc['colors'])
 
         # hooks holds pointers used for user-side customizations
         self.hooks = Struct()
         
         self.strdispatchers = {}
         
         # Set all default hooks, defined in the IPython.hooks module.
         hooks = IPython.hooks
         for hook_name in hooks.__all__:
             # default hooks have priority 100, i.e. low; user hooks should have
             # 0-100 priority
             self.set_hook(hook_name,getattr(hooks,hook_name), 100)
             #print "bound hook",hook_name
 
         # Flag to mark unconditional exit
         self.exit_now = False
 
         self.usage_min =  """\
         An enhanced console for Python.
         Some of its features are:
         - Readline support if the readline library is present.
         - Tab completion in the local namespace.
         - Logging of input, see command-line options.
         - System shell escape via ! , eg !ls.
         - Magic commands, starting with a % (like %ls, %pwd, %cd, etc.)
         - Keeps track of locally defined variables via %who, %whos.
         - Show object information with a ? eg ?x or x? (use ?? for more info).
         """
         if usage: self.usage = usage
         else: self.usage = self.usage_min
 
         # Storage
         self.rc = rc   # This will hold all configuration information
         self.pager = 'less'
         # temporary files used for various purposes.  Deleted at exit.
         self.tempfiles = []
 
         # Keep track of readline usage (later set by init_readline)
         self.has_readline = False
 
         # template for logfile headers.  It gets resolved at runtime by the
         # logstart method.
         self.loghead_tpl = \
 """#log# Automatic Logger file. *** THIS MUST BE THE FIRST LINE ***
 #log# DO NOT CHANGE THIS LINE OR THE TWO BELOW
 #log# opts = %s
 #log# args = %s
 #log# It is safe to make manual edits below here.
 #log#-----------------------------------------------------------------------
 """
         # for pushd/popd management
         try:
             self.home_dir = get_home_dir()
         except HomeDirError,msg:
             fatal(msg)
 
         self.dir_stack = []
 
         # Functions to call the underlying shell.
 
         # The first is similar to os.system, but it doesn't return a value,
         # and it allows interpolation of variables in the user's namespace.
         self.system = lambda cmd: \
                       self.hooks.shell_hook(self.var_expand(cmd,depth=2))
 
         # These are for getoutput and getoutputerror:
         self.getoutput = lambda cmd: \
                          getoutput(self.var_expand(cmd,depth=2),
                                    header=self.rc.system_header,
                                    verbose=self.rc.system_verbose)
 
         self.getoutputerror = lambda cmd: \
                               getoutputerror(self.var_expand(cmd,depth=2),
                                              header=self.rc.system_header,
                                              verbose=self.rc.system_verbose)
  
 
         # keep track of where we started running (mainly for crash post-mortem)
         self.starting_dir = os.getcwd()
 
         # Various switches which can be set
         self.CACHELENGTH = 5000  # this is cheap, it's just text
         self.BANNER = "Python %(version)s on %(platform)s\n" % sys.__dict__
         self.banner2 = banner2
 
         # TraceBack handlers:
 
         # Syntax error handler.
         self.SyntaxTB = SyntaxTB(color_scheme='NoColor')
         
         # The interactive one is initialized with an offset, meaning we always
         # want to remove the topmost item in the traceback, which is our own
         # internal code. Valid modes: ['Plain','Context','Verbose']
         self.InteractiveTB = ultraTB.AutoFormattedTB(mode = 'Plain',
                                                      color_scheme='NoColor',
                                                      tb_offset = 1)
 
         # IPython itself shouldn't crash. This will produce a detailed
         # post-mortem if it does.  But we only install the crash handler for
         # non-threaded shells, the threaded ones use a normal verbose reporter
         # and lose the crash handler.  This is because exceptions in the main
         # thread (such as in GUI code) propagate directly to sys.excepthook,
         # and there's no point in printing crash dumps for every user exception.
         if self.isthreaded:
             ipCrashHandler = ultraTB.FormattedTB()
         else:
             from IPython import CrashHandler
             ipCrashHandler = CrashHandler.IPythonCrashHandler(self)
         self.set_crash_handler(ipCrashHandler)
 
         # and add any custom exception handlers the user may have specified
         self.set_custom_exc(*custom_exceptions)
 
         # indentation management
         self.autoindent = False
         self.indent_current_nsp = 0
 
         # Make some aliases automatically
         # Prepare list of shell aliases to auto-define
         if os.name == 'posix':
             auto_alias = ('mkdir mkdir', 'rmdir rmdir',
                           'mv mv -i','rm rm -i','cp cp -i',
                           'cat cat','less less','clear clear',
                           # a better ls
                           'ls ls -F',
                           # long ls
                           'll ls -lF')
             # Extra ls aliases with color, which need special treatment on BSD
             # variants
             ls_extra = ( # color ls
                          'lc ls -F -o --color',
                          # ls normal files only
                          'lf ls -F -o --color %l | grep ^-',
                          # ls symbolic links
                          'lk ls -F -o --color %l | grep ^l',
                          # directories or links to directories,
                          'ldir ls -F -o --color %l | grep /$',
                          # things which are executable
                          'lx ls -F -o --color %l | grep ^-..x',
                          )
             # The BSDs don't ship GNU ls, so they don't understand the
             # --color switch out of the box
             if 'bsd' in sys.platform:
                 ls_extra = ( # ls normal files only
                              'lf ls -lF | grep ^-',
                              # ls symbolic links
                              'lk ls -lF | grep ^l',
                              # directories or links to directories,
                              'ldir ls -lF | grep /$',
                              # things which are executable
                              'lx ls -lF | grep ^-..x',
                              )
             auto_alias = auto_alias + ls_extra
         elif os.name in ['nt','dos']:
             auto_alias = ('ls dir /on',
                           'ddir dir /ad /on', 'ldir dir /ad /on',
                           'mkdir mkdir','rmdir rmdir','echo echo',
                           'ren ren','cls cls','copy copy')
         else:
             auto_alias = ()
         self.auto_alias = [s.split(None,1) for s in auto_alias]
         
         # Produce a public API instance
         self.api = IPython.ipapi.IPApi(self)
 
         # Initialize all user-visible namespaces
         self.init_namespaces()
         
         # Call the actual (public) initializer
         self.init_auto_alias()
 
         # track which builtins we add, so we can clean up later
         self.builtins_added = {}
         # This method will add the necessary builtins for operation, but
         # tracking what it did via the builtins_added dict.
         
         #TODO: remove this, redundant
         self.add_builtins()
     # end __init__
 
     def var_expand(self,cmd,depth=0):
         """Expand python variables in a string.
 
         The depth argument indicates how many frames above the caller should
         be walked to look for the local namespace where to expand variables.
 
         The global namespace for expansion is always the user's interactive
         namespace.
         """
 
         return str(ItplNS(cmd,
                           self.user_ns,  # globals
                           # Skip our own frame in searching for locals:
                           sys._getframe(depth+1).f_locals # locals
                           ))
 
     def pre_config_initialization(self):
         """Pre-configuration init method
 
         This is called before the configuration files are processed to
         prepare the services the config files might need.
         
         self.rc already has reasonable default values at this point.
         """
         rc = self.rc
         try:
             self.db = pickleshare.PickleShareDB(rc.ipythondir + "/db")
         except exceptions.UnicodeDecodeError:
             print "Your ipythondir can't be decoded to unicode!"
             print "Please set HOME environment variable to something that"
             print r"only has ASCII characters, e.g. c:\home"
             print "Now it is",rc.ipythondir
             sys.exit()
         self.shadowhist = IPython.history.ShadowHist(self.db)
 
     def post_config_initialization(self):
         """Post configuration init method
 
         This is called after the configuration files have been processed to
         'finalize' the initialization."""
 
         rc = self.rc
 
         # Object inspector
         self.inspector = OInspect.Inspector(OInspect.InspectColors,
                                             PyColorize.ANSICodeColors,
                                             'NoColor',
                                             rc.object_info_string_level)
         
         self.rl_next_input = None
         self.rl_do_indent = False
         # Load readline proper
         if rc.readline:
             self.init_readline()
         
         # local shortcut, this is used a LOT
         self.log = self.logger.log
 
         # Initialize cache, set in/out prompts and printing system
         self.outputcache = CachedOutput(self,
                                         rc.cache_size,
                                         rc.pprint,
                                         input_sep = rc.separate_in,
                                         output_sep = rc.separate_out,
                                         output_sep2 = rc.separate_out2,
                                         ps1 = rc.prompt_in1,
                                         ps2 = rc.prompt_in2,
                                         ps_out = rc.prompt_out,
                                         pad_left = rc.prompts_pad_left)
 
         # user may have over-ridden the default print hook:
         try:
             self.outputcache.__class__.display = self.hooks.display
         except AttributeError:
             pass
 
         # I don't like assigning globally to sys, because it means when
         # embedding instances, each embedded instance overrides the previous
         # choice. But sys.displayhook seems to be called internally by exec,
         # so I don't see a way around it.  We first save the original and then
         # overwrite it.
         self.sys_displayhook = sys.displayhook
         sys.displayhook = self.outputcache
 
         # Do a proper resetting of doctest, including the necessary displayhook
         # monkeypatching
         try:
             doctest_reload()
         except ImportError:
             warn("doctest module does not exist.")
         
         # Set user colors (don't do it in the constructor above so that it
         # doesn't crash if colors option is invalid)
         self.magic_colors(rc.colors)
 
         # Set calling of pdb on exceptions
         self.call_pdb = rc.pdb
 
         # Load user aliases
         for alias in rc.alias:
             self.magic_alias(alias)
         
         self.hooks.late_startup_hook()
         
         for cmd in self.rc.autoexec:
             #print "autoexec>",cmd #dbg
             self.api.runlines(cmd)
             
         batchrun = False
         for batchfile in [path(arg) for arg in self.rc.args 
             if arg.lower().endswith('.ipy')]:
             if not batchfile.isfile():
                 print "No such batch file:", batchfile
                 continue
             self.api.runlines(batchfile.text())
             batchrun = True
         # without -i option, exit after running the batch file
         if batchrun and not self.rc.interact:
             self.ask_exit()            
 
     def init_namespaces(self):
         """Initialize all user-visible namespaces to their minimum defaults.
 
         Certain history lists are also initialized here, as they effectively
         act as user namespaces.
 
         Note
         ----
         All data structures here are only filled in, they are NOT reset by this
         method.  If they were not empty before, data will simply be added to
         therm.
         """
         # The user namespace MUST have a pointer to the shell itself.
         self.user_ns[self.name] = self
 
         # Store the public api instance
         self.user_ns['_ip'] = self.api
 
         # make global variables for user access to the histories
         self.user_ns['_ih'] = self.input_hist
         self.user_ns['_oh'] = self.output_hist
         self.user_ns['_dh'] = self.dir_hist
 
         # user aliases to input and output histories
         self.user_ns['In']  = self.input_hist
         self.user_ns['Out'] = self.output_hist
 
         self.user_ns['_sh'] = IPython.shadowns
 
         # Fill the history zero entry, user counter starts at 1
         self.input_hist.append('\n')
         self.input_hist_raw.append('\n')
 
     def add_builtins(self):
         """Store ipython references into the builtin namespace.
 
         Some parts of ipython operate via builtins injected here, which hold a
         reference to IPython itself."""
 
         # TODO: deprecate all of these, they are unsafe
         builtins_new  = dict(__IPYTHON__ = self,
              ip_set_hook = self.set_hook, 
              jobs = self.jobs,
              ipmagic = wrap_deprecated(self.ipmagic,'_ip.magic()'),  
              ipalias = wrap_deprecated(self.ipalias),  
              ipsystem = wrap_deprecated(self.ipsystem,'_ip.system()'),
              #_ip = self.api
              )
         for biname,bival in builtins_new.items():
             try:
                 # store the orignal value so we can restore it
                 self.builtins_added[biname] =  __builtin__.__dict__[biname]
             except KeyError:
                 # or mark that it wasn't defined, and we'll just delete it at
                 # cleanup
                 self.builtins_added[biname] = Undefined
             __builtin__.__dict__[biname] = bival
             
         # Keep in the builtins a flag for when IPython is active.  We set it
         # with setdefault so that multiple nested IPythons don't clobber one
         # another.  Each will increase its value by one upon being activated,
         # which also gives us a way to determine the nesting level.
         __builtin__.__dict__.setdefault('__IPYTHON__active',0)
 
     def clean_builtins(self):
         """Remove any builtins which might have been added by add_builtins, or
         restore overwritten ones to their previous values."""
         for biname,bival in self.builtins_added.items():
             if bival is Undefined:
                 del __builtin__.__dict__[biname]
             else:
                 __builtin__.__dict__[biname] = bival
         self.builtins_added.clear()
     
     def set_hook(self,name,hook, priority = 50, str_key = None, re_key = None):
         """set_hook(name,hook) -> sets an internal IPython hook.
 
         IPython exposes some of its internal API as user-modifiable hooks.  By
         adding your function to one of these hooks, you can modify IPython's 
         behavior to call at runtime your own routines."""
 
         # At some point in the future, this should validate the hook before it
         # accepts it.  Probably at least check that the hook takes the number
         # of args it's supposed to.
         
         f = new.instancemethod(hook,self,self.__class__)
 
         # check if the hook is for strdispatcher first
         if str_key is not None:
             sdp = self.strdispatchers.get(name, StrDispatch())
             sdp.add_s(str_key, f, priority )
             self.strdispatchers[name] = sdp
             return
         if re_key is not None:
             sdp = self.strdispatchers.get(name, StrDispatch())
             sdp.add_re(re.compile(re_key), f, priority )
             self.strdispatchers[name] = sdp
             return
             
         dp = getattr(self.hooks, name, None)
         if name not in IPython.hooks.__all__:
             print "Warning! Hook '%s' is not one of %s" % (name, IPython.hooks.__all__ )
         if not dp:
             dp = IPython.hooks.CommandChainDispatcher()
         
         try:
             dp.add(f,priority)
         except AttributeError:
             # it was not commandchain, plain old func - replace
             dp = f
 
         setattr(self.hooks,name, dp)
         
         
         #setattr(self.hooks,name,new.instancemethod(hook,self,self.__class__))
 
     def set_crash_handler(self,crashHandler):
         """Set the IPython crash handler.
 
         This must be a callable with a signature suitable for use as
         sys.excepthook."""
 
         # Install the given crash handler as the Python exception hook
         sys.excepthook = crashHandler
         
         # The instance will store a pointer to this, so that runtime code
         # (such as magics) can access it.  This is because during the
         # read-eval loop, it gets temporarily overwritten (to deal with GUI
         # frameworks).
         self.sys_excepthook = sys.excepthook
 
 
     def set_custom_exc(self,exc_tuple,handler):
         """set_custom_exc(exc_tuple,handler)
 
         Set a custom exception handler, which will be called if any of the
         exceptions in exc_tuple occur in the mainloop (specifically, in the
         runcode() method.
 
         Inputs:
 
           - exc_tuple: a *tuple* of valid exceptions to call the defined
           handler for.  It is very important that you use a tuple, and NOT A
           LIST here, because of the way Python's except statement works.  If
           you only want to trap a single exception, use a singleton tuple:
 
             exc_tuple == (MyCustomException,)
 
           - handler: this must be defined as a function with the following
           basic interface: def my_handler(self,etype,value,tb).
 
           This will be made into an instance method (via new.instancemethod)
           of IPython itself, and it will be called if any of the exceptions
           listed in the exc_tuple are caught.  If the handler is None, an
           internal basic one is used, which just prints basic info.
 
         WARNING: by putting in your own exception handler into IPython's main
         execution loop, you run a very good chance of nasty crashes.  This
         facility should only be used if you really know what you are doing."""
 
         assert type(exc_tuple)==type(()) , \
                "The custom exceptions must be given AS A TUPLE."
 
         def dummy_handler(self,etype,value,tb):
             print '*** Simple custom exception handler ***'
             print 'Exception type :',etype
             print 'Exception value:',value
             print 'Traceback      :',tb
             print 'Source code    :','\n'.join(self.buffer)
 
         if handler is None: handler = dummy_handler
 
         self.CustomTB = new.instancemethod(handler,self,self.__class__)
         self.custom_exceptions = exc_tuple
 
     def set_custom_completer(self,completer,pos=0):
         """set_custom_completer(completer,pos=0)
 
         Adds a new custom completer function.
 
         The position argument (defaults to 0) is the index in the completers
         list where you want the completer to be inserted."""
 
         newcomp = new.instancemethod(completer,self.Completer,
                                      self.Completer.__class__)
         self.Completer.matchers.insert(pos,newcomp)
 
     def set_completer(self):
         """reset readline's completer to be our own."""
         self.readline.set_completer(self.Completer.complete)
         
     def _get_call_pdb(self):
         return self._call_pdb
 
     def _set_call_pdb(self,val):
 
         if val not in (0,1,False,True):
             raise ValueError,'new call_pdb value must be boolean'
 
         # store value in instance
         self._call_pdb = val
 
         # notify the actual exception handlers
         self.InteractiveTB.call_pdb = val
         if self.isthreaded:
             try:
                 self.sys_excepthook.call_pdb = val
             except:
                 warn('Failed to activate pdb for threaded exception handler')
 
     call_pdb = property(_get_call_pdb,_set_call_pdb,None,
                         'Control auto-activation of pdb at exceptions')
  
     # These special functions get installed in the builtin namespace, to
     # provide programmatic (pure python) access to magics, aliases and system
     # calls.  This is important for logging, user scripting, and more.
 
     # We are basically exposing, via normal python functions, the three
     # mechanisms in which ipython offers special call modes (magics for
     # internal control, aliases for direct system access via pre-selected
     # names, and !cmd for calling arbitrary system commands).
 
     def ipmagic(self,arg_s):
         """Call a magic function by name.
 
         Input: a string containing the name of the magic function to call and any
         additional arguments to be passed to the magic.
 
         ipmagic('name -opt foo bar') is equivalent to typing at the ipython
         prompt:
 
         In[1]: %name -opt foo bar
 
         To call a magic without arguments, simply use ipmagic('name').
 
         This provides a proper Python function to call IPython's magics in any
         valid Python code you can type at the interpreter, including loops and
         compound statements.  It is added by IPython to the Python builtin
         namespace upon initialization."""
 
         args = arg_s.split(' ',1)
         magic_name = args[0]
         magic_name = magic_name.lstrip(self.ESC_MAGIC)
 
         try:
             magic_args = args[1]
         except IndexError:
             magic_args = ''
         fn = getattr(self,'magic_'+magic_name,None)
         if fn is None:
             error("Magic function `%s` not found." % magic_name)
         else:
             magic_args = self.var_expand(magic_args,1)
             return fn(magic_args)
 
     def ipalias(self,arg_s):
         """Call an alias by name.
 
         Input: a string containing the name of the alias to call and any
         additional arguments to be passed to the magic.
 
         ipalias('name -opt foo bar') is equivalent to typing at the ipython
         prompt:
 
         In[1]: name -opt foo bar
 
         To call an alias without arguments, simply use ipalias('name').
 
         This provides a proper Python function to call IPython's aliases in any
         valid Python code you can type at the interpreter, including loops and
         compound statements.  It is added by IPython to the Python builtin
         namespace upon initialization."""
 
         args = arg_s.split(' ',1)
         alias_name = args[0]
         try:
             alias_args = args[1]
         except IndexError:
             alias_args = ''
         if alias_name in self.alias_table:
             self.call_alias(alias_name,alias_args)
         else:
             error("Alias `%s` not found." % alias_name)
 
     def ipsystem(self,arg_s):
         """Make a system call, using IPython."""
 
         self.system(arg_s)
 
     def complete(self,text):
         """Return a sorted list of all possible completions on text.
 
         Inputs:
 
           - text: a string of text to be completed on.
 
         This is a wrapper around the completion mechanism, similar to what
         readline does at the command line when the TAB key is hit.  By
         exposing it as a method, it can be used by other non-readline
         environments (such as GUIs) for text completion.
 
         Simple usage example:
 
         In [7]: x = 'hello'
 
         In [8]: x
         Out[8]: 'hello'
 
         In [9]: print x
         hello
 
         In [10]: _ip.IP.complete('x.l')
         Out[10]: ['x.ljust', 'x.lower', 'x.lstrip']
         """
         
         complete = self.Completer.complete
         state = 0
         # use a dict so we get unique keys, since ipyhton's multiple
         # completers can return duplicates.  When we make 2.4 a requirement,
         # start using sets instead, which are faster.
         comps = {}
         while True:
             newcomp = complete(text,state,line_buffer=text)
             if newcomp is None:
                 break
             comps[newcomp] = 1
             state += 1
         outcomps = comps.keys()
         outcomps.sort()
         #print "T:",text,"OC:",outcomps  # dbg
         #print "vars:",self.user_ns.keys()
         return outcomps
         
     def set_completer_frame(self, frame=None):
         if frame:
             self.Completer.namespace = frame.f_locals
             self.Completer.global_namespace = frame.f_globals
         else:
             self.Completer.namespace = self.user_ns
             self.Completer.global_namespace = self.user_global_ns
 
     def init_auto_alias(self):
         """Define some aliases automatically.
 
         These are ALL parameter-less aliases"""
 
         for alias,cmd in self.auto_alias:
             self.getapi().defalias(alias,cmd)
             
 
     def alias_table_validate(self,verbose=0):
         """Update information about the alias table.
 
         In particular, make sure no Python keywords/builtins are in it."""
 
         no_alias = self.no_alias
         for k in self.alias_table.keys():
             if k in no_alias:
                 del self.alias_table[k]
                 if verbose:
                     print ("Deleting alias <%s>, it's a Python "
                            "keyword or builtin." % k)
     
     def set_autoindent(self,value=None):
         """Set the autoindent flag, checking for readline support.
 
         If called with no arguments, it acts as a toggle."""
 
         if not self.has_readline:
             if os.name == 'posix':
                 warn("The auto-indent feature requires the readline library")
             self.autoindent = 0
             return
         if value is None:
             self.autoindent = not self.autoindent
         else:
             self.autoindent = value
 
     def rc_set_toggle(self,rc_field,value=None):
         """Set or toggle a field in IPython's rc config. structure.
 
         If called with no arguments, it acts as a toggle.
 
         If called with a non-existent field, the resulting AttributeError
         exception will propagate out."""
 
         rc_val = getattr(self.rc,rc_field)
         if value is None:
             value = not rc_val
         setattr(self.rc,rc_field,value)
 
     def user_setup(self,ipythondir,rc_suffix,mode='install'):
         """Install the user configuration directory.
 
         Note
         ----
         DEPRECATED: use the top-level user_setup() function instead.
         """
         return user_setup(ipythondir,rc_suffix,mode)
 
     def atexit_operations(self):
         """This will be executed at the time of exit.
 
         Saving of persistent data should be performed here. """
 
         #print '*** IPython exit cleanup ***' # dbg
         # input history
         self.savehist()
 
         # Cleanup all tempfiles left around
         for tfile in self.tempfiles:
             try:
                 os.unlink(tfile)
             except OSError:
                 pass
 
         # Clear all user namespaces to release all references cleanly.
         self.reset()
 
         # Run user hooks
         self.hooks.shutdown_hook()
 
     def reset(self):
         """Clear all internal namespaces.
 
         Note that this is much more aggressive than %reset, since it clears
         fully all namespaces, as well as all input/output lists.
         """
         for ns in self.ns_refs_table:
             ns.clear()
 
         # Clear input and output histories
         self.input_hist[:] = []
         self.input_hist_raw[:] = []
         self.output_hist.clear()
         # Restore the user namespaces to minimal usability
         self.init_namespaces()
         
     def savehist(self):
         """Save input history to a file (via readline library)."""
 
         if not self.has_readline:
             return
         
         try:
             self.readline.write_history_file(self.histfile)
         except:
             print 'Unable to save IPython command history to file: ' + \
                   `self.histfile`
 
     def reloadhist(self):
         """Reload the input history from disk file."""
 
         if self.has_readline:
             try:
                 self.readline.clear_history()
                 self.readline.read_history_file(self.shell.histfile)
             except AttributeError:
                 pass
             
 
     def history_saving_wrapper(self, func):
         """ Wrap func for readline history saving
         
         Convert func into callable that saves & restores
         history around the call """
         
         if not self.has_readline:
             return func
         
         def wrapper():
             self.savehist()
             try:
                 func()
             finally:
                 readline.read_history_file(self.histfile)
         return wrapper
             
     def pre_readline(self):
         """readline hook to be used at the start of each line.
 
         Currently it handles auto-indent only."""
 
         #debugx('self.indent_current_nsp','pre_readline:')
 
         if self.rl_do_indent:
             self.readline.insert_text(self.indent_current_str())
         if self.rl_next_input is not None:
             self.readline.insert_text(self.rl_next_input)
             self.rl_next_input = None
 
     def init_readline(self):
         """Command history completion/saving/reloading."""
 
 
         import IPython.rlineimpl as readline
                   
         if not readline.have_readline:
             self.has_readline = 0
             self.readline = None
             # no point in bugging windows users with this every time:
             warn('Readline services not available on this platform.')
         else:
             sys.modules['readline'] = readline
             import atexit
             from IPython.completer import IPCompleter
             self.Completer = IPCompleter(self,
                                             self.user_ns,
                                             self.user_global_ns,
                                             self.rc.readline_omit__names,
                                             self.alias_table)
             sdisp = self.strdispatchers.get('complete_command', StrDispatch())
             self.strdispatchers['complete_command'] = sdisp
             self.Completer.custom_completers = sdisp
             # Platform-specific configuration
             if os.name == 'nt':
                 self.readline_startup_hook = readline.set_pre_input_hook
             else:
                 self.readline_startup_hook = readline.set_startup_hook
 
             # Load user's initrc file (readline config)
             # Or if libedit is used, load editrc.
             inputrc_name = os.environ.get('INPUTRC')
             if inputrc_name is None:
                 home_dir = get_home_dir()
                 if home_dir is not None:
                     inputrc_name = '.inputrc'
                     if readline.uses_libedit:
                         inputrc_name = '.editrc'
                     inputrc_name = os.path.join(home_dir, inputrc_name)
             if os.path.isfile(inputrc_name):
                 try:
                     readline.read_init_file(inputrc_name)
                 except:
                     warn('Problems reading readline initialization file <%s>'
                          % inputrc_name)
             
             self.has_readline = 1
             self.readline = readline
             # save this in sys so embedded copies can restore it properly
             sys.ipcompleter = self.Completer.complete
             self.set_completer()
 
             # Configure readline according to user's prefs
             # This is only done if GNU readline is being used.  If libedit
             # is being used (as on Leopard) the readline config is
             # not run as the syntax for libedit is different.
             if not readline.uses_libedit:
                 for rlcommand in self.rc.readline_parse_and_bind:
                     #print "loading rl:",rlcommand  # dbg
                     readline.parse_and_bind(rlcommand)
 
             # remove some chars from the delimiters list
             delims = readline.get_completer_delims()
             delims = delims.translate(string._idmap,
                                       self.rc.readline_remove_delims)
             readline.set_completer_delims(delims)
             # otherwise we end up with a monster history after a while:
             readline.set_history_length(1000)
             try:
                 #print '*** Reading readline history'  # dbg
                 readline.read_history_file(self.histfile)
             except IOError:
                 pass  # It doesn't exist yet.
 
             atexit.register(self.atexit_operations)
             del atexit
 
         # Configure auto-indent for all platforms
         self.set_autoindent(self.rc.autoindent)
 
     def ask_yes_no(self,prompt,default=True):
         if self.rc.quiet:
             return True
         return ask_yes_no(prompt,default)
 
-    def cache_main_mod(self,mod,fname=None):
-        """Cache a main module.
+    def new_main_mod(self,ns=None):
+        """Return a new 'main' module object for user code execution.
+        """
+        main_mod = self._user_main_module
+        init_fakemod_dict(main_mod,ns)
+        return main_mod
+
+    def cache_main_mod(self,ns,fname):
+        """Cache a main module's namespace.
 
-        When scripts are executed via %run, we must keep a reference to their
-        __main__ module (a FakeModule instance) around so that Python doesn't
-        clear it, rendering objects defined therein useless.
+        When scripts are executed via %run, we must keep a reference to the
+        namespace of their __main__ module (a FakeModule instance) around so
+        that Python doesn't clear it, rendering objects defined therein
+        useless.
 
         This method keeps said reference in a private dict, keyed by the
         absolute path of the module object (which corresponds to the script
         path).  This way, for multiple executions of the same script we only
-        keep one copy of __main__ (the last one), thus preventing memory leaks
-        from old references while allowing the objects from the last execution
-        to be accessible.
+        keep one copy of the namespace (the last one), thus preventing memory
+        leaks from old references while allowing the objects from the last
+        execution to be accessible.
+
+        Note: we can not allow the actual FakeModule instances to be deleted,
+        because of how Python tears down modules (it hard-sets all their
+        references to None without regard for reference counts).  This method
+        must therefore make a *copy* of the given namespace, to allow the
+        original module's __dict__ to be cleared and reused.
 
+        
         Parameters
         ----------
-          mod : a module object
+          ns : a namespace (a dict, typically)
+
+          fname : str
+            Filename associated with the namespace.
 
         Examples
         --------
 
         In [10]: import IPython
 
-        In [11]: _ip.IP.cache_main_mod(IPython)
+        In [11]: _ip.IP.cache_main_mod(IPython.__dict__,IPython.__file__)
 
-        In [12]: IPython.__file__ in _ip.IP._user_main_modules
+        In [12]: IPython.__file__ in _ip.IP._main_ns_cache
         Out[12]: True
         """
-        if fname is None:
-            fname = mod.__file__
-        #print >> sys.stderr, 'CFNAME  :', os.path.abspath(fname)  # dbg
-        self._user_main_modules[os.path.abspath(fname)] = mod
+        self._main_ns_cache[os.path.abspath(fname)] = ns.copy()
 
     def clear_main_mod_cache(self):
         """Clear the cache of main modules.
 
         Mainly for use by utilities like %reset.
 
         Examples
         --------
 
         In [15]: import IPython
 
-        In [16]: _ip.IP.cache_main_mod(IPython)
+        In [16]: _ip.IP.cache_main_mod(IPython.__dict__,IPython.__file__)
 
-        In [17]: len(_ip.IP._user_main_modules) > 0
+        In [17]: len(_ip.IP._main_ns_cache) > 0
         Out[17]: True
 
         In [18]: _ip.IP.clear_main_mod_cache()
 
-        In [19]: len(_ip.IP._user_main_modules) == 0
+        In [19]: len(_ip.IP._main_ns_cache) == 0
         Out[19]: True
         """
-        self._user_main_modules.clear()
+        self._main_ns_cache.clear()
 
     def _should_recompile(self,e):
         """Utility routine for edit_syntax_error"""
 
         if e.filename in ('<ipython console>','<input>','<string>',
                           '<console>','<BackgroundJob compilation>',
                           None):
                               
             return False
         try:
             if (self.rc.autoedit_syntax and 
                 not self.ask_yes_no('Return to editor to correct syntax error? '
                               '[Y/n] ','y')):
                 return False
         except EOFError:
             return False
 
         def int0(x):
             try:
                 return int(x)
             except TypeError:
                 return 0
         # always pass integer line and offset values to editor hook
         try:
             self.hooks.fix_error_editor(e.filename,
                 int0(e.lineno),int0(e.offset),e.msg)
         except IPython.ipapi.TryNext:
             warn('Could not open editor')
             return False
         return True
         
     def edit_syntax_error(self):
         """The bottom half of the syntax error handler called in the main loop.
 
         Loop until syntax error is fixed or user cancels.
         """
 
         while self.SyntaxTB.last_syntax_error:
             # copy and clear last_syntax_error
             err = self.SyntaxTB.clear_err_state()
             if not self._should_recompile(err):
                 return
             try:
                 # may set last_syntax_error again if a SyntaxError is raised
                 self.safe_execfile(err.filename,self.user_ns)
             except:
                 self.showtraceback()
             else:
                 try:
                     f = file(err.filename)
                     try:
                         sys.displayhook(f.read())
                     finally:
                         f.close()
                 except:
                     self.showtraceback()
 
     def showsyntaxerror(self, filename=None):
         """Display the syntax error that just occurred.
 
         This doesn't display a stack trace because there isn't one.
 
         If a filename is given, it is stuffed in the exception instead
         of what was there before (because Python's parser always uses
         "<string>" when reading from a string).
         """
         etype, value, last_traceback = sys.exc_info()
 
         # See note about these variables in showtraceback() below
         sys.last_type = etype
         sys.last_value = value
         sys.last_traceback = last_traceback
         
         if filename and etype is SyntaxError:
             # Work hard to stuff the correct filename in the exception
             try:
                 msg, (dummy_filename, lineno, offset, line) = value
             except:
                 # Not the format we expect; leave it alone
                 pass
             else:
                 # Stuff in the right filename
                 try:
                     # Assume SyntaxError is a class exception
                     value = SyntaxError(msg, (filename, lineno, offset, line))
                 except:
                     # If that failed, assume SyntaxError is a string
                     value = msg, (filename, lineno, offset, line)
         self.SyntaxTB(etype,value,[])
 
     def debugger(self,force=False):
         """Call the pydb/pdb debugger.
 
         Keywords:
 
           - force(False): by default, this routine checks the instance call_pdb
           flag and does not actually invoke the debugger if the flag is false.
           The 'force' option forces the debugger to activate even if the flag
           is false.
         """
 
         if not (force or self.call_pdb):
             return
 
         if not hasattr(sys,'last_traceback'):
             error('No traceback has been produced, nothing to debug.')
             return
 
         # use pydb if available
         if Debugger.has_pydb:
             from pydb import pm
         else:
             # fallback to our internal debugger
             pm = lambda : self.InteractiveTB.debugger(force=True)
         self.history_saving_wrapper(pm)()
 
     def showtraceback(self,exc_tuple = None,filename=None,tb_offset=None):
         """Display the exception that just occurred.
 
         If nothing is known about the exception, this is the method which
         should be used throughout the code for presenting user tracebacks,
         rather than directly invoking the InteractiveTB object.
 
         A specific showsyntaxerror() also exists, but this method can take
         care of calling it if needed, so unless you are explicitly catching a
         SyntaxError exception, don't try to analyze the stack manually and
         simply call this method."""
 
         
         # Though this won't be called by syntax errors in the input line,
         # there may be SyntaxError cases whith imported code.
         
         try:
             if exc_tuple is None:
                 etype, value, tb = sys.exc_info()
             else:
                 etype, value, tb = exc_tuple
     
             if etype is SyntaxError:
                 self.showsyntaxerror(filename)
             elif etype is IPython.ipapi.UsageError:
                 print "UsageError:", value
             else:
                 # WARNING: these variables are somewhat deprecated and not
                 # necessarily safe to use in a threaded environment, but tools
                 # like pdb depend on their existence, so let's set them.  If we
                 # find problems in the field, we'll need to revisit their use.
                 sys.last_type = etype
                 sys.last_value = value
                 sys.last_traceback = tb
     
                 if etype in self.custom_exceptions:
                     self.CustomTB(etype,value,tb)
                 else:
                     self.InteractiveTB(etype,value,tb,tb_offset=tb_offset)
                     if self.InteractiveTB.call_pdb and self.has_readline:
                         # pdb mucks up readline, fix it back
                         self.set_completer()
         except KeyboardInterrupt:
             self.write("\nKeyboardInterrupt\n")
 
     def mainloop(self,banner=None):
         """Creates the local namespace and starts the mainloop.
 
         If an optional banner argument is given, it will override the
         internally created default banner."""
 
         if self.rc.c:  # Emulate Python's -c option
             self.exec_init_cmd()
         if banner is None:
             if not self.rc.banner:
                 banner = ''
             # banner is string? Use it directly!
             elif isinstance(self.rc.banner,basestring):
                 banner = self.rc.banner
             else:                
                 banner = self.BANNER+self.banner2
 
         # if you run stuff with -c <cmd>, raw hist is not updated
         # ensure that it's in sync
         if len(self.input_hist) != len (self.input_hist_raw):
             self.input_hist_raw = InputList(self.input_hist)
 
         while 1:
             try:
                 self.interact(banner)
                 #self.interact_with_readline()                
 
                 # XXX for testing of a readline-decoupled repl loop, call
                 # interact_with_readline above
 
                 break
             except KeyboardInterrupt:
                 # this should not be necessary, but KeyboardInterrupt
                 # handling seems rather unpredictable...
                 self.write("\nKeyboardInterrupt in interact()\n")
 
     def exec_init_cmd(self):
         """Execute a command given at the command line.
 
         This emulates Python's -c option."""
 
         #sys.argv = ['-c']
         self.push(self.prefilter(self.rc.c, False))
         if not self.rc.interact:
             self.ask_exit()
 
     def embed_mainloop(self,header='',local_ns=None,global_ns=None,stack_depth=0):
         """Embeds IPython into a running python program.
 
         Input:
 
           - header: An optional header message can be specified.
 
           - local_ns, global_ns: working namespaces. If given as None, the
           IPython-initialized one is updated with __main__.__dict__, so that
           program variables become visible but user-specific configuration
           remains possible.
 
           - stack_depth: specifies how many levels in the stack to go to
           looking for namespaces (when local_ns and global_ns are None).  This
           allows an intermediate caller to make sure that this function gets
           the namespace from the intended level in the stack.  By default (0)
           it will get its locals and globals from the immediate caller.
 
         Warning: it's possible to use this in a program which is being run by
         IPython itself (via %run), but some funny things will happen (a few
         globals get overwritten). In the future this will be cleaned up, as
         there is no fundamental reason why it can't work perfectly."""
 
         # Get locals and globals from caller
         if local_ns is None or global_ns is None:
             call_frame = sys._getframe(stack_depth).f_back
 
             if local_ns is None:
                 local_ns = call_frame.f_locals
             if global_ns is None:
                 global_ns = call_frame.f_globals
 
         # Update namespaces and fire up interpreter
 
         # The global one is easy, we can just throw it in
         self.user_global_ns = global_ns
 
         # but the user/local one is tricky: ipython needs it to store internal
         # data, but we also need the locals.  We'll copy locals in the user
         # one, but will track what got copied so we can delete them at exit.
         # This is so that a later embedded call doesn't see locals from a
         # previous call (which most likely existed in a separate scope).
         local_varnames = local_ns.keys()
         self.user_ns.update(local_ns)
         #self.user_ns['local_ns'] = local_ns  # dbg
 
         # Patch for global embedding to make sure that things don't overwrite
         # user globals accidentally. Thanks to Richard <[e-mail]>
         # FIXME. Test this a bit more carefully (the if.. is new)
         if local_ns is None and global_ns is None:
             self.user_global_ns.update(__main__.__dict__)
 
         # make sure the tab-completer has the correct frame information, so it
         # actually completes using the frame's locals/globals
         self.set_completer_frame()
 
         # before activating the interactive mode, we need to make sure that
         # all names in the builtin namespace needed by ipython point to
         # ourselves, and not to other instances.
         self.add_builtins()
 
         self.interact(header)
         
         # now, purge out the user namespace from anything we might have added
         # from the caller's local namespace
         delvar = self.user_ns.pop
         for var in local_varnames:
             delvar(var,None)
         # and clean builtins we may have overridden
         self.clean_builtins()
 
     def interact_prompt(self):
         """ Print the prompt (in read-eval-print loop) 
 
         Provided for those who want to implement their own read-eval-print loop (e.g. GUIs), not 
         used in standard IPython flow.
         """
         if self.more:
             try:
                 prompt = self.hooks.generate_prompt(True)
             except:
                 self.showtraceback()
             if self.autoindent:
                 self.rl_do_indent = True
 
         else:
             try:
                 prompt = self.hooks.generate_prompt(False)
             except:
                 self.showtraceback()
         self.write(prompt)
 
     def interact_handle_input(self,line):
         """ Handle the input line (in read-eval-print loop)
         
         Provided for those who want to implement their own read-eval-print loop (e.g. GUIs), not 
         used in standard IPython flow.        
         """
         if line.lstrip() == line:
             self.shadowhist.add(line.strip())
         lineout = self.prefilter(line,self.more)
 
         if line.strip():
             if self.more:
                 self.input_hist_raw[-1] += '%s\n' % line
             else:
                 self.input_hist_raw.append('%s\n' % line)                
 
         
         self.more = self.push(lineout)
         if (self.SyntaxTB.last_syntax_error and
             self.rc.autoedit_syntax):
             self.edit_syntax_error()
 
     def interact_with_readline(self):
         """ Demo of using interact_handle_input, interact_prompt
         
         This is the main read-eval-print loop. If you need to implement your own (e.g. for GUI),
         it should work like this.
         """ 
         self.readline_startup_hook(self.pre_readline)
         while not self.exit_now:
             self.interact_prompt()
             if self.more:
                 self.rl_do_indent = True
             else:
                 self.rl_do_indent = False
             line = raw_input_original().decode(self.stdin_encoding)
             self.interact_handle_input(line)
 
         
     def interact(self, banner=None):
         """Closely emulate the interactive Python console.
 
         The optional banner argument specify the banner to print
         before the first interaction; by default it prints a banner
         similar to the one printed by the real Python interpreter,
         followed by the current class name in parentheses (so as not
         to confuse this with the real interpreter -- since it's so
         close!).
 
         """
         
         if self.exit_now:
             # batch run -> do not interact
             return
         cprt = 'Type "copyright", "credits" or "license" for more information.'
         if banner is None:
             self.write("Python %s on %s\n%s\n(%s)\n" %
                        (sys.version, sys.platform, cprt,
                         self.__class__.__name__))
         else:
             self.write(banner)
 
         more = 0
         
         # Mark activity in the builtins
         __builtin__.__dict__['__IPYTHON__active'] += 1
         
         if self.has_readline:
             self.readline_startup_hook(self.pre_readline)
         # exit_now is set by a call to %Exit or %Quit, through the
         # ask_exit callback.
         
         while not self.exit_now:
             self.hooks.pre_prompt_hook()
             if more:
                 try:
                     prompt = self.hooks.generate_prompt(True)
                 except:
                     self.showtraceback()
                 if self.autoindent:
                     self.rl_do_indent = True
                     
             else:
                 try:
                     prompt = self.hooks.generate_prompt(False)
                 except:
                     self.showtraceback()
             try:
                 line = self.raw_input(prompt,more)
                 if self.exit_now:
                     # quick exit on sys.std[in|out] close
                     break
                 if self.autoindent:
                     self.rl_do_indent = False
                     
             except KeyboardInterrupt:
                 #double-guard against keyboardinterrupts during kbdint handling
                 try:
                     self.write('\nKeyboardInterrupt\n')
                     self.resetbuffer()
                     # keep cache in sync with the prompt counter:
                     self.outputcache.prompt_count -= 1
     
                     if self.autoindent:
                         self.indent_current_nsp = 0
                     more = 0
                 except KeyboardInterrupt:
                     pass
             except EOFError:
                 if self.autoindent:
                     self.rl_do_indent = False
                     self.readline_startup_hook(None)
                 self.write('\n')
                 self.exit()
             except bdb.BdbQuit:
                 warn('The Python debugger has exited with a BdbQuit exception.\n'
                      'Because of how pdb handles the stack, it is impossible\n'
                      'for IPython to properly format this particular exception.\n'
                      'IPython will resume normal operation.')
             except:
                 # exceptions here are VERY RARE, but they can be triggered
                 # asynchronously by signal handlers, for example.
                 self.showtraceback()
             else:
                 more = self.push(line)
                 if (self.SyntaxTB.last_syntax_error and
                     self.rc.autoedit_syntax):
                     self.edit_syntax_error()
             
         # We are off again...
         __builtin__.__dict__['__IPYTHON__active'] -= 1
 
     def excepthook(self, etype, value, tb):
       """One more defense for GUI apps that call sys.excepthook.
 
       GUI frameworks like wxPython trap exceptions and call
       sys.excepthook themselves.  I guess this is a feature that
       enables them to keep running after exceptions that would
       otherwise kill their mainloop. This is a bother for IPython
       which excepts to catch all of the program exceptions with a try:
       except: statement.
 
       Normally, IPython sets sys.excepthook to a CrashHandler instance, so if
       any app directly invokes sys.excepthook, it will look to the user like
       IPython crashed.  In order to work around this, we can disable the
       CrashHandler and replace it with this excepthook instead, which prints a
       regular traceback using our InteractiveTB.  In this fashion, apps which
       call sys.excepthook will generate a regular-looking exception from
       IPython, and the CrashHandler will only be triggered by real IPython
       crashes.
 
       This hook should be used sparingly, only in places which are not likely
       to be true IPython errors.
       """
       self.showtraceback((etype,value,tb),tb_offset=0)
 
     def expand_aliases(self,fn,rest):
         """ Expand multiple levels of aliases:
         
         if:
         
         alias foo bar /tmp
         alias baz foo
         
         then:
         
         baz huhhahhei -> bar /tmp huhhahhei
         
         """
         line = fn + " " + rest
         
         done = set()
         while 1:
             pre,fn,rest = prefilter.splitUserInput(line,
                                                    prefilter.shell_line_split)
             if fn in self.alias_table:
                 if fn in done:
                     warn("Cyclic alias definition, repeated '%s'" % fn)
                     return ""
                 done.add(fn)
 
                 l2 = self.transform_alias(fn,rest)
                 # dir -> dir 
                 # print "alias",line, "->",l2  #dbg
                 if l2 == line:
                     break
                 # ls -> ls -F should not recurse forever
                 if l2.split(None,1)[0] == line.split(None,1)[0]:
                     line = l2
                     break
                 
                 line=l2
                 
                 
                 # print "al expand to",line #dbg
             else:
                 break
                 
         return line
 
     def transform_alias(self, alias,rest=''):
         """ Transform alias to system command string.
         """
         trg = self.alias_table[alias]
 
         nargs,cmd = trg
         # print trg #dbg
         if ' ' in cmd and os.path.isfile(cmd):
             cmd = '"%s"' % cmd
 
         # Expand the %l special to be the user's input line
         if cmd.find('%l') >= 0:
             cmd = cmd.replace('%l',rest)
             rest = ''
         if nargs==0:
             # Simple, argument-less aliases
             cmd = '%s %s' % (cmd,rest)
         else:
             # Handle aliases with positional arguments
             args = rest.split(None,nargs)
             if len(args)< nargs:
                 error('Alias <%s> requires %s arguments, %s given.' %
                       (alias,nargs,len(args)))
                 return None
             cmd = '%s %s' % (cmd % tuple(args[:nargs]),' '.join(args[nargs:]))
         # Now call the macro, evaluating in the user's namespace
         #print 'new command: <%r>' % cmd  # dbg
         return cmd
         
     def call_alias(self,alias,rest=''):
         """Call an alias given its name and the rest of the line.
 
         This is only used to provide backwards compatibility for users of
         ipalias(), use of which is not recommended for anymore."""
 
         # Now call the macro, evaluating in the user's namespace
         cmd = self.transform_alias(alias, rest)
         try:
             self.system(cmd)
         except:
             self.showtraceback()
 
     def indent_current_str(self):
         """return the current level of indentation as a string"""
         return self.indent_current_nsp * ' '
 
     def autoindent_update(self,line):
         """Keep track of the indent level."""
 
         #debugx('line')
         #debugx('self.indent_current_nsp')
         if self.autoindent:
             if line:
                 inisp = num_ini_spaces(line)
                 if inisp < self.indent_current_nsp:
                     self.indent_current_nsp = inisp
 
                 if line[-1] == ':':
                     self.indent_current_nsp += 4
                 elif dedent_re.match(line):
                     self.indent_current_nsp -= 4
             else:
                 self.indent_current_nsp = 0
 
     def runlines(self,lines):
         """Run a string of one or more lines of source.
 
         This method is capable of running a string containing multiple source
         lines, as if they had been entered at the IPython prompt.  Since it
         exposes IPython's processing machinery, the given strings can contain
         magic calls (%magic), special shell access (!cmd), etc."""
 
         # We must start with a clean buffer, in case this is run from an
         # interactive IPython session (via a magic, for example).
         self.resetbuffer()
         lines = lines.split('\n')
         more = 0
     
         for line in lines:
             # skip blank lines so we don't mess up the prompt counter, but do
             # NOT skip even a blank line if we are in a code block (more is
             # true)
             
             if line or more:
                 # push to raw history, so hist line numbers stay in sync
                 self.input_hist_raw.append("# " + line + "\n")
                 more = self.push(self.prefilter(line,more))
                 # IPython's runsource returns None if there was an error
                 # compiling the code.  This allows us to stop processing right
                 # away, so the user gets the error message at the right place.
                 if more is None:
                     break
             else:
                 self.input_hist_raw.append("\n")
         # final newline in case the input didn't have it, so that the code
         # actually does get executed
         if more:
             self.push('\n')
 
     def runsource(self, source, filename='<input>', symbol='single'):
         """Compile and run some source in the interpreter.
 
         Arguments are as for compile_command().
 
         One several things can happen:
 
         1) The input is incorrect; compile_command() raised an
         exception (SyntaxError or OverflowError).  A syntax traceback
         will be printed by calling the showsyntaxerror() method.
 
         2) The input is incomplete, and more input is required;
         compile_command() returned None.  Nothing happens.
 
         3) The input is complete; compile_command() returned a code
         object.  The code is executed by calling self.runcode() (which
         also handles run-time exceptions, except for SystemExit).
 
         The return value is:
 
           - True in case 2
 
           - False in the other cases, unless an exception is raised, where
           None is returned instead.  This can be used by external callers to
           know whether to continue feeding input or not.
 
         The return value can be used to decide whether to use sys.ps1 or
         sys.ps2 to prompt the next line."""
 
         # if the source code has leading blanks, add 'if 1:\n' to it
         # this allows execution of indented pasted code. It is tempting
         # to add '\n' at the end of source to run commands like ' a=1'
         # directly, but this fails for more complicated scenarios
         source=source.encode(self.stdin_encoding)
         if source[:1] in [' ', '\t']:
             source = 'if 1:\n%s' % source
 
         try:
             code = self.compile(source,filename,symbol)
         except (OverflowError, SyntaxError, ValueError, TypeError):
             # Case 1
             self.showsyntaxerror(filename)
             return None
 
         if code is None:
             # Case 2
             return True
 
         # Case 3
         # We store the code object so that threaded shells and
         # custom exception handlers can access all this info if needed.
         # The source corresponding to this can be obtained from the
         # buffer attribute as '\n'.join(self.buffer).
         self.code_to_run = code
         # now actually execute the code object
         if self.runcode(code) == 0:
             return False
         else:
             return None
 
     def runcode(self,code_obj):
         """Execute a code object.
 
         When an exception occurs, self.showtraceback() is called to display a
         traceback.
 
         Return value: a flag indicating whether the code to be run completed
         successfully:
 
           - 0: successful execution.
           - 1: an error occurred.
         """
 
         # Set our own excepthook in case the user code tries to call it
         # directly, so that the IPython crash handler doesn't get triggered
         old_excepthook,sys.excepthook = sys.excepthook, self.excepthook
 
         # we save the original sys.excepthook in the instance, in case config
         # code (such as magics) needs access to it.
         self.sys_excepthook = old_excepthook
         outflag = 1  # happens in more places, so it's easier as default
         try:
             try:
                 self.hooks.pre_runcode_hook()
                 exec code_obj in self.user_global_ns, self.user_ns
             finally:
                 # Reset our crash handler in place
                 sys.excepthook = old_excepthook
         except SystemExit:
             self.resetbuffer()
             self.showtraceback()
             warn("Type %exit or %quit to exit IPython "
                  "(%Exit or %Quit do so unconditionally).",level=1)
         except self.custom_exceptions:
             etype,value,tb = sys.exc_info()
             self.CustomTB(etype,value,tb)
         except:
             self.showtraceback()
         else:
             outflag = 0
             if softspace(sys.stdout, 0):
                 print
         # Flush out code object which has been run (and source)
         self.code_to_run = None
         return outflag
         
     def push(self, line):
         """Push a line to the interpreter.
 
         The line should not have a trailing newline; it may have
         internal newlines.  The line is appended to a buffer and the
         interpreter's runsource() method is called with the
         concatenated contents of the buffer as source.  If this
         indicates that the command was executed or invalid, the buffer
         is reset; otherwise, the command is incomplete, and the buffer
         is left as it was after the line was appended.  The return
         value is 1 if more input is required, 0 if the line was dealt
         with in some way (this is the same as runsource()).
         """
 
         # autoindent management should be done here, and not in the
         # interactive loop, since that one is only seen by keyboard input.  We
         # need this done correctly even for code run via runlines (which uses
         # push).
 
         #print 'push line: <%s>' % line  # dbg
         for subline in line.splitlines():
             self.autoindent_update(subline)
         self.buffer.append(line)
         more = self.runsource('\n'.join(self.buffer), self.filename)
         if not more:
             self.resetbuffer()
         return more
 
     def split_user_input(self, line):
         # This is really a hold-over to support ipapi and some extensions
         return prefilter.splitUserInput(line)
 
     def resetbuffer(self):
         """Reset the input buffer."""
         self.buffer[:] = []
         
     def raw_input(self,prompt='',continue_prompt=False):
         """Write a prompt and read a line.
 
         The returned line does not include the trailing newline.
         When the user enters the EOF key sequence, EOFError is raised.
 
         Optional inputs:
 
           - prompt(''): a string to be printed to prompt the user.
 
           - continue_prompt(False): whether this line is the first one or a
           continuation in a sequence of inputs.
         """
 
         # Code run by the user may have modified the readline completer state.
         # We must ensure that our completer is back in place.
         if self.has_readline:
             self.set_completer()
         
         try:
             line = raw_input_original(prompt).decode(self.stdin_encoding)
         except ValueError:
             warn("\n********\nYou or a %run:ed script called sys.stdin.close()"
                  " or sys.stdout.close()!\nExiting IPython!")
             self.ask_exit()
             return ""
 
         # Try to be reasonably smart about not re-indenting pasted input more
         # than necessary.  We do this by trimming out the auto-indent initial
         # spaces, if the user's actual input started itself with whitespace.
         #debugx('self.buffer[-1]')
 
         if self.autoindent:
             if num_ini_spaces(line) > self.indent_current_nsp:
                 line = line[self.indent_current_nsp:]
                 self.indent_current_nsp = 0
             
         # store the unfiltered input before the user has any chance to modify
         # it.
         if line.strip():
             if continue_prompt:
                 self.input_hist_raw[-1] += '%s\n' % line
                 if self.has_readline: # and some config option is set?
                     try:
                         histlen = self.readline.get_current_history_length()
                         if histlen > 1:
                             newhist = self.input_hist_raw[-1].rstrip()
                             self.readline.remove_history_item(histlen-1)
                             self.readline.replace_history_item(histlen-2,
                                             newhist.encode(self.stdin_encoding))
                     except AttributeError:
                         pass # re{move,place}_history_item are new in 2.4.                
             else:
                 self.input_hist_raw.append('%s\n' % line)                
             # only entries starting at first column go to shadow history
             if line.lstrip() == line:
                 self.shadowhist.add(line.strip())
         elif not continue_prompt:
             self.input_hist_raw.append('\n')
         try:
             lineout = self.prefilter(line,continue_prompt)
         except:
             # blanket except, in case a user-defined prefilter crashes, so it
             # can't take all of ipython with it.
             self.showtraceback()
             return ''
         else:
             return lineout
 
     def _prefilter(self, line, continue_prompt):
         """Calls different preprocessors, depending on the form of line."""
 
         # All handlers *must* return a value, even if it's blank ('').
 
         # Lines are NOT logged here. Handlers should process the line as
         # needed, update the cache AND log it (so that the input cache array
         # stays synced).
 
         #.....................................................................
         # Code begins
 
         #if line.startswith('%crash'): raise RuntimeError,'Crash now!'  # dbg
 
         # save the line away in case we crash, so the post-mortem handler can
         # record it
         self._last_input_line = line
 
         #print '***line: <%s>' % line # dbg
 
         if not line:
             # Return immediately on purely empty lines, so that if the user
             # previously typed some whitespace that started a continuation
             # prompt, he can break out of that loop with just an empty line.
             # This is how the default python prompt works.
 
             # Only return if the accumulated input buffer was just whitespace!
             if ''.join(self.buffer).isspace():
                 self.buffer[:] = []
             return ''
         
         line_info = prefilter.LineInfo(line, continue_prompt)
         
         # the input history needs to track even empty lines
         stripped = line.strip()
         
         if not stripped:
             if not continue_prompt:
                 self.outputcache.prompt_count -= 1
             return self.handle_normal(line_info)
 
         # print '***cont',continue_prompt  # dbg
         # special handlers are only allowed for single line statements
         if continue_prompt and not self.rc.multi_line_specials:
             return self.handle_normal(line_info)
 
 
         # See whether any pre-existing handler can take care of it  
         rewritten = self.hooks.input_prefilter(stripped)
         if rewritten != stripped: # ok, some prefilter did something
             rewritten = line_info.pre + rewritten  # add indentation
             return self.handle_normal(prefilter.LineInfo(rewritten,
                                                          continue_prompt))
             
         #print 'pre <%s> iFun <%s> rest <%s>' % (pre,iFun,theRest)  # dbg
         
         return prefilter.prefilter(line_info, self)
 
 
     def _prefilter_dumb(self, line, continue_prompt):
         """simple prefilter function, for debugging"""
         return self.handle_normal(line,continue_prompt)
 
     
     def multiline_prefilter(self, line, continue_prompt):
         """ Run _prefilter for each line of input
         
         Covers cases where there are multiple lines in the user entry,
         which is the case when the user goes back to a multiline history
         entry and presses enter.
         
         """
         out = []
         for l in line.rstrip('\n').split('\n'):
             out.append(self._prefilter(l, continue_prompt))
         return '\n'.join(out)
     
     # Set the default prefilter() function (this can be user-overridden)
     prefilter = multiline_prefilter
 
     def handle_normal(self,line_info):
         """Handle normal input lines. Use as a template for handlers."""
 
         # With autoindent on, we need some way to exit the input loop, and I
         # don't want to force the user to have to backspace all the way to
         # clear the line.  The rule will be in this case, that either two
         # lines of pure whitespace in a row, or a line of pure whitespace but
         # of a size different to the indent level, will exit the input loop.
         line = line_info.line
         continue_prompt = line_info.continue_prompt
         
         if (continue_prompt and self.autoindent and line.isspace() and
             (0 < abs(len(line) - self.indent_current_nsp) <= 2 or
              (self.buffer[-1]).isspace() )):
             line = ''
 
         self.log(line,line,continue_prompt)
         return line
 
     def handle_alias(self,line_info):
         """Handle alias input lines. """
         tgt = self.alias_table[line_info.iFun]
         # print "=>",tgt #dbg
         if callable(tgt):
             if '$' in line_info.line:
                 call_meth = '(_ip, _ip.itpl(%s))'
             else:
                 call_meth = '(_ip,%s)'
             line_out = ("%s_sh.%s" + call_meth) % (line_info.preWhitespace,
                                          line_info.iFun, 
             make_quoted_expr(line_info.line))
         else:
             transformed = self.expand_aliases(line_info.iFun,line_info.theRest)
 
             # pre is needed, because it carries the leading whitespace.  Otherwise
             # aliases won't work in indented sections.
             line_out = '%s_ip.system(%s)' % (line_info.preWhitespace,
                                              make_quoted_expr( transformed ))
         
         self.log(line_info.line,line_out,line_info.continue_prompt)
         #print 'line out:',line_out # dbg
         return line_out
 
     def handle_shell_escape(self, line_info):
         """Execute the line in a shell, empty return value"""
         #print 'line in :', `line` # dbg
         line = line_info.line
         if line.lstrip().startswith('!!'):
             # rewrite LineInfo's line, iFun and theRest to properly hold the
             # call to %sx and the actual command to be executed, so
             # handle_magic can work correctly.  Note that this works even if
             # the line is indented, so it handles multi_line_specials
             # properly.
             new_rest = line.lstrip()[2:]
             line_info.line = '%ssx %s' % (self.ESC_MAGIC,new_rest)
             line_info.iFun = 'sx'
             line_info.theRest = new_rest
             return self.handle_magic(line_info)
         else:
             cmd = line.lstrip().lstrip('!')
             line_out = '%s_ip.system(%s)' % (line_info.preWhitespace,
                                              make_quoted_expr(cmd))
         # update cache/log and return
         self.log(line,line_out,line_info.continue_prompt)
         return line_out
 
     def handle_magic(self, line_info):
         """Execute magic functions."""
         iFun    = line_info.iFun
         theRest = line_info.theRest
         cmd = '%s_ip.magic(%s)' % (line_info.preWhitespace,
                                    make_quoted_expr(iFun + " " + theRest))
         self.log(line_info.line,cmd,line_info.continue_prompt)
         #print 'in handle_magic, cmd=<%s>' % cmd  # dbg
         return cmd
 
     def handle_auto(self, line_info):
         """Hande lines which can be auto-executed, quoting if requested."""
 
         line    = line_info.line
         iFun    = line_info.iFun
         theRest = line_info.theRest
         pre     = line_info.pre
         continue_prompt = line_info.continue_prompt
         obj = line_info.ofind(self)['obj']
 
         #print 'pre <%s> iFun <%s> rest <%s>' % (pre,iFun,theRest)  # dbg
 
         # This should only be active for single-line input!
         if continue_prompt:
             self.log(line,line,continue_prompt)
             return line
 
         force_auto = isinstance(obj, IPython.ipapi.IPyAutocall)
         auto_rewrite = True
         
         if pre == self.ESC_QUOTE:
             # Auto-quote splitting on whitespace
             newcmd = '%s("%s")' % (iFun,'", "'.join(theRest.split()) )
         elif pre == self.ESC_QUOTE2:
             # Auto-quote whole string
             newcmd = '%s("%s")' % (iFun,theRest)
         elif pre == self.ESC_PAREN:
             newcmd = '%s(%s)' % (iFun,",".join(theRest.split()))
         else:
             # Auto-paren.
             # We only apply it to argument-less calls if the autocall
             # parameter is set to 2.  We only need to check that autocall is <
             # 2, since this function isn't called unless it's at least 1.
             if not theRest and (self.rc.autocall < 2) and not force_auto:
                 newcmd = '%s %s' % (iFun,theRest)
                 auto_rewrite = False
             else:
                 if not force_auto and theRest.startswith('['):
                     if hasattr(obj,'__getitem__'):
                         # Don't autocall in this case: item access for an object
                         # which is BOTH callable and implements __getitem__.
                         newcmd = '%s %s' % (iFun,theRest)
                         auto_rewrite = False
                     else:
                         # if the object doesn't support [] access, go ahead and
                         # autocall
                         newcmd = '%s(%s)' % (iFun.rstrip(),theRest)
                 elif theRest.endswith(';'):
                     newcmd = '%s(%s);' % (iFun.rstrip(),theRest[:-1])
                 else:
                     newcmd = '%s(%s)' % (iFun.rstrip(), theRest)
 
         if auto_rewrite:
             rw = self.outputcache.prompt1.auto_rewrite() + newcmd
             
             try:
                 # plain ascii works better w/ pyreadline, on some machines, so
                 # we use it and only print uncolored rewrite if we have unicode
                 rw = str(rw)
                 print >>Term.cout, rw
             except UnicodeEncodeError:
                 print "-------------->" + newcmd
             
         # log what is now valid Python, not the actual user input (without the
         # final newline)
         self.log(line,newcmd,continue_prompt)
         return newcmd
 
     def handle_help(self, line_info):
         """Try to get some help for the object.
 
         obj? or ?obj   -> basic information.
         obj?? or ??obj -> more details.
         """
         
         line = line_info.line
         # We need to make sure that we don't process lines which would be
         # otherwise valid python, such as "x=1 # what?"
         try:
             codeop.compile_command(line)
         except SyntaxError:
             # We should only handle as help stuff which is NOT valid syntax
             if line[0]==self.ESC_HELP:
                 line = line[1:]
             elif line[-1]==self.ESC_HELP:
                 line = line[:-1]
             self.log(line,'#?'+line,line_info.continue_prompt)
             if line:
                 #print 'line:<%r>' % line  # dbg
                 self.magic_pinfo(line)
             else:
                 page(self.usage,screen_lines=self.rc.screen_length)
             return '' # Empty string is needed here!
         except:
             # Pass any other exceptions through to the normal handler
             return self.handle_normal(line_info)
         else:
             # If the code compiles ok, we should handle it normally
             return self.handle_normal(line_info)
 
     def getapi(self):
         """ Get an IPApi object for this shell instance
         
         Getting an IPApi object is always preferable to accessing the shell
         directly, but this holds true especially for extensions.
         
         It should always be possible to implement an extension with IPApi
         alone. If not, contact maintainer to request an addition.
         
         """
         return self.api
 
     def handle_emacs(self, line_info):
         """Handle input lines marked by python-mode."""
 
         # Currently, nothing is done.  Later more functionality can be added
         # here if needed.
 
         # The input cache shouldn't be updated
         return line_info.line
     
 
     def mktempfile(self,data=None):
         """Make a new tempfile and return its filename.
 
         This makes a call to tempfile.mktemp, but it registers the created
         filename internally so ipython cleans it up at exit time.
 
         Optional inputs:
 
           - data(None): if data is given, it gets written out to the temp file
           immediately, and the file is closed again."""
 
         filename = tempfile.mktemp('.py','ipython_edit_')
         self.tempfiles.append(filename)
         
         if data:
             tmp_file = open(filename,'w')
             tmp_file.write(data)
             tmp_file.close()
         return filename
 
     def write(self,data):
         """Write a string to the default output"""
         Term.cout.write(data)
 
     def write_err(self,data):
         """Write a string to the default error output"""
         Term.cerr.write(data)
 
     def ask_exit(self):
         """ Call for exiting. Can be overiden and used as a callback. """
         self.exit_now = True
 
     def exit(self):
         """Handle interactive exit.
 
         This method calls the ask_exit callback."""
 
         if self.rc.confirm_exit:
             if self.ask_yes_no('Do you really want to exit ([y]/n)?','y'):
                 self.ask_exit()
         else:
             self.ask_exit()
 
     def safe_execfile(self,fname,*where,**kw):
         """A safe version of the builtin execfile().
 
         This version will never throw an exception, and knows how to handle
         ipython logs as well.
 
         :Parameters:
           fname : string
             Name of the file to be executed.
             
           where : tuple
             One or two namespaces, passed to execfile() as (globals,locals).
             If only one is given, it is passed as both.
 
         :Keywords:
           islog : boolean (False)
 
           quiet : boolean (True)
 
           exit_ignore : boolean (False)
           """
 
         def syspath_cleanup():
             """Internal cleanup routine for sys.path."""
             if add_dname:
                 try:
                     sys.path.remove(dname)
                 except ValueError:
                     # For some reason the user has already removed it, ignore.
                     pass
         
         fname = os.path.expanduser(fname)
 
         # Find things also in current directory.  This is needed to mimic the
         # behavior of running a script from the system command line, where
         # Python inserts the script's directory into sys.path
         dname = os.path.dirname(os.path.abspath(fname))
         add_dname = False
         if dname not in sys.path:
             sys.path.insert(0,dname)
             add_dname = True
 
         try:
             xfile = open(fname)
         except:
             print >> Term.cerr, \
                   'Could not open file <%s> for safe execution.' % fname
             syspath_cleanup()
             return None
 
         kw.setdefault('islog',0)
         kw.setdefault('quiet',1)
         kw.setdefault('exit_ignore',0)
         
         first = xfile.readline()
         loghead = str(self.loghead_tpl).split('\n',1)[0].strip()
         xfile.close()
         # line by line execution
         if first.startswith(loghead) or kw['islog']:
             print 'Loading log file <%s> one line at a time...' % fname
             if kw['quiet']:
                 stdout_save = sys.stdout
                 sys.stdout = StringIO.StringIO()
             try:
                 globs,locs = where[0:2]
             except:
                 try:
                     globs = locs = where[0]
                 except:
                     globs = locs = globals()
             badblocks = []
 
             # we also need to identify indented blocks of code when replaying
             # logs and put them together before passing them to an exec
             # statement. This takes a bit of regexp and look-ahead work in the
             # file. It's easiest if we swallow the whole thing in memory
             # first, and manually walk through the lines list moving the
             # counter ourselves.
             indent_re = re.compile('\s+\S')
             xfile = open(fname)
             filelines = xfile.readlines()
             xfile.close()
             nlines = len(filelines)
             lnum = 0
             while lnum < nlines:
                 line = filelines[lnum]
                 lnum += 1
                 # don't re-insert logger status info into cache
                 if line.startswith('#log#'):
                     continue
                 else:
                     # build a block of code (maybe a single line) for execution
                     block = line
                     try:
                         next = filelines[lnum] # lnum has already incremented
                     except:
                         next = None
                     while next and indent_re.match(next):
                         block += next
                         lnum += 1
                         try:
                             next = filelines[lnum]
                         except:
                             next = None
                     # now execute the block of one or more lines
                     try:
                         exec block in globs,locs
                     except SystemExit:
                         pass
                     except:
                         badblocks.append(block.rstrip())
             if kw['quiet']:  # restore stdout
                 sys.stdout.close()
                 sys.stdout = stdout_save
             print 'Finished replaying log file <%s>' % fname
             if badblocks:
                 print >> sys.stderr, ('\nThe following lines/blocks in file '
                                       '<%s> reported errors:' % fname)
                     
                 for badline in badblocks:
                     print >> sys.stderr, badline
         else:  # regular file execution
             try:
                 if sys.platform == 'win32' and sys.version_info < (2,5,1):
                     # Work around a bug in Python for Windows.  The bug was
                     # fixed in in Python 2.5 r54159 and 54158, but that's still
                     # SVN Python as of March/07.  For details, see:
                     # http://projects.scipy.org/ipython/ipython/ticket/123
                     try:
                         globs,locs = where[0:2]
                     except:
                         try:
                             globs = locs = where[0]
                         except:
                             globs = locs = globals()
                     exec file(fname) in globs,locs
                 else:
                     execfile(fname,*where)
             except SyntaxError:
                 self.showsyntaxerror()
                 warn('Failure executing file: <%s>' % fname)
             except SystemExit,status:
                 # Code that correctly sets the exit status flag to success (0)
                 # shouldn't be bothered with a traceback.  Note that a plain
                 # sys.exit() does NOT set the message to 0 (it's empty) so that
                 # will still get a traceback.  Note that the structure of the
                 # SystemExit exception changed between Python 2.4 and 2.5, so
                 # the checks must be done in a version-dependent way.
                 show = False
 
                 if sys.version_info[:2] > (2,5):
                     if status.message!=0 and not kw['exit_ignore']:
                         show = True
                 else:
                     if status.code and not kw['exit_ignore']:
                         show = True
                 if show:
                     self.showtraceback()
                     warn('Failure executing file: <%s>' % fname)
             except:
                 self.showtraceback()
                 warn('Failure executing file: <%s>' % fname)
 
         syspath_cleanup()
 
 #************************* end of file <iplib.py> *****************************

IPython/tests/test_magic.py

@@ -1,149 +1,151 b''
 """Tests for various magic functions.
 
 Needs to be run by nose (to make ipython session available).
 """
 
 # Standard library imports
 import os
 import sys
 
 # Third-party imports
 import nose.tools as nt
 
 # From our own code
 from IPython.testing import decorators as dec
 
 #-----------------------------------------------------------------------------
 # Test functions begin
 
 def test_rehashx():
     # clear up everything
     _ip.IP.alias_table.clear()
     del _ip.db['syscmdlist']
     
     _ip.magic('rehashx')
     # Practically ALL ipython development systems will have more than 10 aliases
 
     assert len(_ip.IP.alias_table) > 10
     for key, val in _ip.IP.alias_table.items():
         # we must strip dots from alias names
         assert '.' not in key
 
     # rehashx must fill up syscmdlist
     scoms = _ip.db['syscmdlist']
     assert len(scoms) > 10
 
 
 def doctest_run_ns():
     """Classes declared %run scripts must be instantiable afterwards.
 
     In [11]: run tclass foo
 
     In [12]: isinstance(f(),foo)
     Out[12]: True
     """
 
     
 def doctest_run_ns2():
     """Classes declared %run scripts must be instantiable afterwards.
 
     In [4]: run tclass C-first_pass
 
     In [5]: run tclass C-second_pass
     tclass.py: deleting object: C-first_pass
     """
 
 
 def doctest_hist_f():
     """Test %hist -f with temporary filename.
 
     In [9]: import tempfile
 
     In [10]: tfile = tempfile.mktemp('.py','tmp-ipython-')
 
     In [11]: %history -n -f $tfile 3
     """
 
 
 def doctest_hist_r():
     """Test %hist -r
 
     XXX - This test is not recording the output correctly.  Not sure why...
 
     In [6]: x=1
 
     In [7]: hist -n -r 2
     x=1  # random
     hist -n -r 2  # random
     """
 
 
 def test_obj_del():
     """Test that object's __del__ methods are called on exit."""
     test_dir = os.path.dirname(__file__)
     del_file = os.path.join(test_dir,'obj_del.py')
     out = _ip.IP.getoutput('ipython %s' % del_file)
     nt.assert_equals(out,'obj_del.py: object A deleted')
 
 
 def test_shist():
     # Simple tests of ShadowHist class - test generator.
     import os, shutil, tempfile
 
     from IPython.Extensions import pickleshare
     from IPython.history import ShadowHist
     
     tfile = tempfile.mktemp('','tmp-ipython-')
     
     db = pickleshare.PickleShareDB(tfile)
     s = ShadowHist(db)
     s.add('hello')
     s.add('world')
     s.add('hello')
     s.add('hello')
     s.add('karhu')
 
     yield nt.assert_equals,s.all(),[(1, 'hello'), (2, 'world'), (3, 'karhu')]
     
     yield nt.assert_equal,s.get(2),'world'
     
     shutil.rmtree(tfile)
     
 @dec.skipif_not_numpy
 def test_numpy_clear_array_undec():
     _ip.ex('import numpy as np')
     _ip.ex('a = np.empty(2)')
     
     yield nt.assert_true,'a' in _ip.user_ns
     _ip.magic('clear array')
     yield nt.assert_false,'a' in _ip.user_ns
     
 
 @dec.skip()
 def test_fail_dec(*a,**k):
     yield nt.assert_true, False
 
 @dec.skip('This one shouldn not run')
 def test_fail_dec2(*a,**k):
     yield nt.assert_true, False
 
 @dec.skipknownfailure
 def test_fail_dec3(*a,**k):
     yield nt.assert_true, False
 
 
 def doctest_refbug():
     """Very nasty problem with references held by multiple runs of a script.
     See: https://bugs.launchpad.net/ipython/+bug/269966
 
+    In [1]: _ip.IP.clear_main_mod_cache()
+    
     In [2]: run refbug
 
     In [3]: call_f()
     lowercased: hello
 
     In [4]: run refbug
 
     In [5]: call_f()
     lowercased: hello
     lowercased: hello
     """