- Fix a bug introduced by r1357 which broke embedding.

- Add a %kill_embedded magic so one can permanently deactivate an embedded
instance.

IPython/Shell.py

@@ -1,1116 +1,1143 b''
 # -*- coding: utf-8 -*-
 """IPython Shell classes.
 
 All the matplotlib support code was co-developed with John Hunter,
 matplotlib's author.
 
-$Id: Shell.py 2222 2007-04-06 17:11:27Z fperez $"""
+$Id: Shell.py 2577 2007-08-02 23:50:02Z fperez $"""
 
 #*****************************************************************************
 #       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.
 #*****************************************************************************
 
 from IPython import Release
 __author__  = '%s <%s>' % Release.authors['Fernando']
 __license__ = Release.license
 
 # Code begins
 # Stdlib imports
 import __builtin__
 import __main__
 import Queue
 import inspect
 import os
 import sys
 import thread
 import threading
 import time
 
 from signal import signal, SIGINT
 
 try:
     import ctypes
     HAS_CTYPES = True
 except ImportError:
     HAS_CTYPES = False
 
 # IPython imports
 import IPython
-from IPython import ultraTB
-from IPython.genutils import Term,warn,error,flag_calls
+from IPython import ultraTB, ipapi
+from IPython.genutils import Term,warn,error,flag_calls, ask_yes_no
 from IPython.iplib import InteractiveShell
 from IPython.ipmaker import make_IPython
 from IPython.Magic import Magic
 from IPython.ipstruct import Struct
 
 # Globals
 # global flag to pass around information about Ctrl-C without exceptions
 KBINT = False
 
 # global flag to turn on/off Tk support.
 USE_TK = False
 
 # ID for the main thread, used for cross-thread exceptions
 MAIN_THREAD_ID = thread.get_ident()
 
 # Tag when runcode() is active, for exception handling
 CODE_RUN = None
 
 #-----------------------------------------------------------------------------
 # This class is trivial now, but I want to have it in to publish a clean
 # interface. Later when the internals are reorganized, code that uses this
 # shouldn't have to change.
 
 class IPShell:
     """Create an IPython instance."""
     
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,
                  debug=1,shell_class=InteractiveShell):
         self.IP = make_IPython(argv,user_ns=user_ns,
                                user_global_ns=user_global_ns,
                                debug=debug,shell_class=shell_class)
 
     def mainloop(self,sys_exit=0,banner=None):
         self.IP.mainloop(banner)
         if sys_exit:
             sys.exit()
 
 #-----------------------------------------------------------------------------
+def kill_embedded(self,parameter_s=''):
+    """%kill_embedded : deactivate for good the current embedded IPython.
+
+    This function (after asking for confirmation) sets an internal flag so that
+    an embedded IPython will never activate again.  This is useful to
+    permanently disable a shell that is being called inside a loop: once you've
+    figured out what you needed from it, you may then kill it and the program
+    will then continue to run without the interactive shell interfering again.
+    """
+    
+    kill = ask_yes_no("Are you sure you want to kill this embedded instance "
+                     "(y/n)? [y/N] ",'n')
+    if kill:
+        self.shell.embedded_active = False
+        print "This embedded IPython will not reactivate anymore once you exit."
+    
 class IPShellEmbed:
     """Allow embedding an IPython shell into a running program.
 
     Instances of this class are callable, with the __call__ method being an
     alias to the embed() method of an InteractiveShell instance.
 
     Usage (see also the example-embed.py file for a running example):
 
     ipshell = IPShellEmbed([argv,banner,exit_msg,rc_override])
 
     - argv: list containing valid command-line options for IPython, as they
     would appear in sys.argv[1:].
 
     For example, the following command-line options:
 
       $ ipython -prompt_in1 'Input <\\#>' -colors LightBG
 
     would be passed in the argv list as:
 
       ['-prompt_in1','Input <\\#>','-colors','LightBG']
 
     - banner: string which gets printed every time the interpreter starts.
 
     - exit_msg: string which gets printed every time the interpreter exits.
 
     - rc_override: a dict or Struct of configuration options such as those
     used by IPython. These options are read from your ~/.ipython/ipythonrc
     file when the Shell object is created. Passing an explicit rc_override
     dict with any options you want allows you to override those values at
     creation time without having to modify the file. This way you can create
     embeddable instances configured in any way you want without editing any
     global files (thus keeping your interactive IPython configuration
     unchanged).
 
     Then the ipshell instance can be called anywhere inside your code:
     
     ipshell(header='') -> Opens up an IPython shell.
 
     - header: string printed by the IPython shell upon startup. This can let
     you know where in your code you are when dropping into the shell. Note
     that 'banner' gets prepended to all calls, so header is used for
     location-specific information.
 
     For more details, see the __call__ method below.
 
     When the IPython shell is exited with Ctrl-D, normal program execution
     resumes.
 
     This functionality was inspired by a posting on comp.lang.python by cmkl
     <[e-mail]> on Dec. 06/01 concerning similar uses of pyrepl, and
     by the IDL stop/continue commands."""
 
     def __init__(self,argv=None,banner='',exit_msg=None,rc_override=None,
                  user_ns=None):
         """Note that argv here is a string, NOT a list."""
         self.set_banner(banner)
         self.set_exit_msg(exit_msg)
         self.set_dummy_mode(0)
 
         # sys.displayhook is a global, we need to save the user's original
         # Don't rely on __displayhook__, as the user may have changed that.
         self.sys_displayhook_ori = sys.displayhook
 
         # save readline completer status
         try:
             #print 'Save completer',sys.ipcompleter  # dbg
             self.sys_ipcompleter_ori = sys.ipcompleter
         except:
             pass # not nested with IPython
         
         self.IP = make_IPython(argv,rc_override=rc_override,
                                embedded=True,
                                user_ns=user_ns)
 
+        ip = ipapi.IPApi(self.IP)
+        ip.expose_magic("kill_embedded",kill_embedded)
+
         # copy our own displayhook also
         self.sys_displayhook_embed = sys.displayhook
         # and leave the system's display hook clean
         sys.displayhook = self.sys_displayhook_ori
         # don't use the ipython crash handler so that user exceptions aren't
         # trapped
         sys.excepthook = ultraTB.FormattedTB(color_scheme = self.IP.rc.colors,
                                              mode = self.IP.rc.xmode,
                                              call_pdb = self.IP.rc.pdb)
         self.restore_system_completer()
 
     def restore_system_completer(self):
         """Restores the readline completer which was in place.
 
         This allows embedded IPython within IPython not to disrupt the
         parent's completion.
         """
         
         try:
             self.IP.readline.set_completer(self.sys_ipcompleter_ori)
             sys.ipcompleter = self.sys_ipcompleter_ori
         except:
             pass
 
     def __call__(self,header='',local_ns=None,global_ns=None,dummy=None):
         """Activate the interactive interpreter.
 
         __call__(self,header='',local_ns=None,global_ns,dummy=None) -> Start
         the interpreter shell with the given local and global namespaces, and
         optionally print a header string at startup.
 
         The shell can be globally activated/deactivated using the
         set/get_dummy_mode methods. This allows you to turn off a shell used
         for debugging globally.
 
         However, *each* time you call the shell you can override the current
         state of dummy_mode with the optional keyword parameter 'dummy'. For
         example, if you set dummy mode on with IPShell.set_dummy_mode(1), you
         can still have a specific call work by making it as IPShell(dummy=0).
 
         The optional keyword parameter dummy controls whether the call
         actually does anything.  """
 
+        # If the user has turned it off, go away
+        if not self.IP.embedded_active:
+            return
+
+        # Normal exits from interactive mode set this flag, so the shell can't
+        # re-enter (it checks this variable at the start of interactive mode).
+        self.IP.exit_now = False
+
         # Allow the dummy parameter to override the global __dummy_mode
         if dummy or (dummy != 0 and self.__dummy_mode):
             return
 
         # Set global subsystems (display,completions) to our values
         sys.displayhook = self.sys_displayhook_embed
         if self.IP.has_readline:
             self.IP.set_completer()
 
         if self.banner and header:
             format = '%s\n%s\n'
         else:
             format = '%s%s\n'
         banner =  format % (self.banner,header)
 
         # Call the embedding code with a stack depth of 1 so it can skip over
         # our call and get the original caller's namespaces.
         self.IP.embed_mainloop(banner,local_ns,global_ns,stack_depth=1)
 
         if self.exit_msg:
             print self.exit_msg
             
         # Restore global systems (display, completion)
         sys.displayhook = self.sys_displayhook_ori
         self.restore_system_completer()
     
     def set_dummy_mode(self,dummy):
         """Sets the embeddable shell's dummy mode parameter.
 
         set_dummy_mode(dummy): dummy = 0 or 1.
 
         This parameter is persistent and makes calls to the embeddable shell
         silently return without performing any action. This allows you to
         globally activate or deactivate a shell you're using with a single call.
 
         If you need to manually"""
 
         if dummy not in [0,1,False,True]:
             raise ValueError,'dummy parameter must be boolean'
         self.__dummy_mode = dummy
 
     def get_dummy_mode(self):
         """Return the current value of the dummy mode parameter.
         """
         return self.__dummy_mode
     
     def set_banner(self,banner):
         """Sets the global banner.
 
         This banner gets prepended to every header printed when the shell
         instance is called."""
 
         self.banner = banner
 
     def set_exit_msg(self,exit_msg):
         """Sets the global exit_msg.
 
         This exit message gets printed upon exiting every time the embedded
         shell is called. It is None by default. """
 
         self.exit_msg = exit_msg
 
 #-----------------------------------------------------------------------------
 if HAS_CTYPES:
     #  Add async exception support.  Trick taken from:
     # http://sebulba.wikispaces.com/recipe+thread2
     def _async_raise(tid, exctype):
         """raises the exception, performs cleanup if needed"""
         if not inspect.isclass(exctype):
             raise TypeError("Only types can be raised (not instances)")
         res = ctypes.pythonapi.PyThreadState_SetAsyncExc(tid,
                                                          ctypes.py_object(exctype))
         if res == 0:
             raise ValueError("invalid thread id")
         elif res != 1:
             # """if it returns a number greater than one, you're in trouble, 
             # and you should call it again with exc=NULL to revert the effect"""
             ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, 0)
             raise SystemError("PyThreadState_SetAsyncExc failed")
 
     def sigint_handler (signum,stack_frame):
         """Sigint handler for threaded apps.
 
         This is a horrible hack to pass information about SIGINT _without_
         using exceptions, since I haven't been able to properly manage
         cross-thread exceptions in GTK/WX.  In fact, I don't think it can be
         done (or at least that's my understanding from a c.l.py thread where
         this was discussed)."""
 
         global KBINT
 
         if CODE_RUN:
             _async_raise(MAIN_THREAD_ID,KeyboardInterrupt)
         else:
             KBINT = True
             print '\nKeyboardInterrupt - Press <Enter> to continue.',
             Term.cout.flush()
 
 else:
     def sigint_handler (signum,stack_frame):
         """Sigint handler for threaded apps.
 
         This is a horrible hack to pass information about SIGINT _without_
         using exceptions, since I haven't been able to properly manage
         cross-thread exceptions in GTK/WX.  In fact, I don't think it can be
         done (or at least that's my understanding from a c.l.py thread where
         this was discussed)."""
 
         global KBINT
 
         print '\nKeyboardInterrupt - Press <Enter> to continue.',
         Term.cout.flush()
         # Set global flag so that runsource can know that Ctrl-C was hit
         KBINT = True
 
 
 class MTInteractiveShell(InteractiveShell):
     """Simple multi-threaded shell."""
 
     # Threading strategy taken from:
     # http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/65109, by Brian
     # McErlean and John Finlay.  Modified with corrections by Antoon Pardon,
     # from the pygtk mailing list, to avoid lockups with system calls.
 
     # class attribute to indicate whether the class supports threads or not.
     # Subclasses with thread support should override this as needed.
     isthreaded = True
 
     def __init__(self,name,usage=None,rc=Struct(opts=None,args=None),
                  user_ns=None,user_global_ns=None,banner2='',**kw):
         """Similar to the normal InteractiveShell, but with threading control"""
         
         InteractiveShell.__init__(self,name,usage,rc,user_ns,
                                   user_global_ns,banner2)
 
         # Locking control variable.  We need to use a norma lock, not an RLock
         # here.  I'm not exactly sure why, it seems to me like it should be
         # the opposite, but we deadlock with an RLock.  Puzzled...
         self.thread_ready = threading.Condition(threading.Lock())
 
         # A queue to hold the code to be executed.  A scalar variable is NOT
         # enough, because uses like macros cause reentrancy.
         self.code_queue = Queue.Queue()
 
         # Stuff to do at closing time
         self._kill = False
         on_kill = kw.get('on_kill')
         if on_kill is None:
             on_kill = []
         # Check that all things to kill are callable:
         for t in on_kill:
             if not callable(t):
                 raise TypeError,'on_kill must be a list of callables'
         self.on_kill = on_kill
 
     def runsource(self, source, filename="<input>", symbol="single"):
         """Compile and run some source in the interpreter.
 
         Modified version of code.py's runsource(), to handle threading issues.
         See the original for full docstring details."""
 
         global KBINT
         
         # If Ctrl-C was typed, we reset the flag and return right away
         if KBINT:
             KBINT = False
             return False
         
         try:
             code = self.compile(source, filename, symbol)
         except (OverflowError, SyntaxError, ValueError):
             # Case 1
             self.showsyntaxerror(filename)
             return False
 
         if code is None:
             # Case 2
             return True
 
         # Case 3
         # Store code in queue, so the execution thread can handle it.
 
         # Note that with macros and other applications, we MAY re-enter this
         # section, so we have to acquire the lock with non-blocking semantics,
         # else we deadlock.
         got_lock = self.thread_ready.acquire(False)
         self.code_queue.put(code)
         if got_lock:
             self.thread_ready.wait()  # Wait until processed in timeout interval
             self.thread_ready.release()
 
         return False
 
     def runcode(self):
         """Execute a code object.
 
         Multithreaded wrapper around IPython's runcode()."""
 
         global CODE_RUN
 
         # Exceptions need to be raised differently depending on which thread is
         # active
         CODE_RUN = True
         
         # lock thread-protected stuff
         got_lock = self.thread_ready.acquire(False)
 
         if self._kill:
             print >>Term.cout, 'Closing threads...',
             Term.cout.flush()
             for tokill in self.on_kill:
                 tokill()
             print >>Term.cout, 'Done.'
 
         # Install sigint handler.  We do it every time to ensure that if user
         # code modifies it, we restore our own handling.
         try:
             signal(SIGINT,sigint_handler)
         except SystemError:
             # This happens under Windows, which seems to have all sorts
             # of problems with signal handling.  Oh well...
             pass
 
         # Flush queue of pending code by calling the run methood of the parent
         # class with all items which may be in the queue.
         while 1:
             try:
                 code_to_run = self.code_queue.get_nowait()
             except Queue.Empty:
                 break
             if got_lock:
                 self.thread_ready.notify()
                 InteractiveShell.runcode(self,code_to_run)
             else:
                 break
             
         # We're done with thread-protected variables
         if got_lock:
             self.thread_ready.release()
 
         # We're done...
         CODE_RUN = False
         # This MUST return true for gtk threading to work
         return True
 
     def kill(self):
         """Kill the thread, returning when it has been shut down."""
         got_lock = self.thread_ready.acquire(False)
         self._kill = True
         if got_lock:
             self.thread_ready.release()
 
 class MatplotlibShellBase:
     """Mixin class to provide the necessary modifications to regular IPython
     shell classes for matplotlib support.
 
     Given Python's MRO, this should be used as the FIRST class in the
     inheritance hierarchy, so that it overrides the relevant methods."""
     
     def _matplotlib_config(self,name,user_ns):
         """Return items needed to setup the user's shell with matplotlib"""
 
         # Initialize matplotlib to interactive mode always
         import matplotlib
         from matplotlib import backends
         matplotlib.interactive(True)
 
         def use(arg):
             """IPython wrapper for matplotlib's backend switcher.
 
             In interactive use, we can not allow switching to a different
             interactive backend, since thread conflicts will most likely crash
             the python interpreter.  This routine does a safety check first,
             and refuses to perform a dangerous switch.  It still allows
             switching to non-interactive backends."""
 
             if arg in backends.interactive_bk and arg != self.mpl_backend:
                 m=('invalid matplotlib backend switch.\n'
                    'This script attempted to switch to the interactive '
                    'backend: `%s`\n'
                    'Your current choice of interactive backend is: `%s`\n\n'
                    'Switching interactive matplotlib backends at runtime\n'
                    'would crash the python interpreter, '
                    'and IPython has blocked it.\n\n'
                    'You need to either change your choice of matplotlib backend\n'
                    'by editing your .matplotlibrc file, or run this script as a \n'
                    'standalone file from the command line, not using IPython.\n' %
                    (arg,self.mpl_backend) )
                 raise RuntimeError, m
             else:
                 self.mpl_use(arg)
                 self.mpl_use._called = True
         
         self.matplotlib = matplotlib
         self.mpl_backend = matplotlib.rcParams['backend']
 
         # we also need to block switching of interactive backends by use()
         self.mpl_use = matplotlib.use
         self.mpl_use._called = False
         # overwrite the original matplotlib.use with our wrapper
         matplotlib.use = use
 
         # This must be imported last in the matplotlib series, after
         # backend/interactivity choices have been made
         import matplotlib.pylab as pylab
         self.pylab = pylab
 
         self.pylab.show._needmain = False
         # We need to detect at runtime whether show() is called by the user.
         # For this, we wrap it into a decorator which adds a 'called' flag.
         self.pylab.draw_if_interactive = flag_calls(self.pylab.draw_if_interactive)
 
         # Build a user namespace initialized with matplotlib/matlab features.
         user_ns = IPython.ipapi.make_user_ns(user_ns)
 
         exec ("import matplotlib\n"
               "import matplotlib.pylab as pylab\n") in user_ns
         
         # Build matplotlib info banner
         b="""
   Welcome to pylab, a matplotlib-based Python environment.
   For more information, type 'help(pylab)'.
 """
         return user_ns,b
 
     def mplot_exec(self,fname,*where,**kw):
         """Execute a matplotlib script.
 
         This is a call to execfile(), but wrapped in safeties to properly
         handle interactive rendering and backend switching."""
 
         #print '*** Matplotlib runner ***' # dbg
         # turn off rendering until end of script
         isInteractive = self.matplotlib.rcParams['interactive']
         self.matplotlib.interactive(False)
         self.safe_execfile(fname,*where,**kw)
         self.matplotlib.interactive(isInteractive)
         # make rendering call now, if the user tried to do it
         if self.pylab.draw_if_interactive.called:
             self.pylab.draw()
             self.pylab.draw_if_interactive.called = False
                 
         # if a backend switch was performed, reverse it now
         if self.mpl_use._called:
             self.matplotlib.rcParams['backend'] = self.mpl_backend
         
     def magic_run(self,parameter_s=''):
         Magic.magic_run(self,parameter_s,runner=self.mplot_exec)
 
     # Fix the docstring so users see the original as well
     magic_run.__doc__ = "%s\n%s" % (Magic.magic_run.__doc__,
                                     "\n        *** Modified %run for Matplotlib,"
                                     " with proper interactive handling ***")
 
 # Now we provide 2 versions of a matplotlib-aware IPython base shells, single
 # and multithreaded.  Note that these are meant for internal use, the IPShell*
 # classes below are the ones meant for public consumption.
 
 class MatplotlibShell(MatplotlibShellBase,InteractiveShell):
     """Single-threaded shell with matplotlib support."""
 
     def __init__(self,name,usage=None,rc=Struct(opts=None,args=None),
                  user_ns=None,user_global_ns=None,**kw):
         user_ns,b2 = self._matplotlib_config(name,user_ns)
         InteractiveShell.__init__(self,name,usage,rc,user_ns,user_global_ns,
                                   banner2=b2,**kw)
 
 class MatplotlibMTShell(MatplotlibShellBase,MTInteractiveShell):
     """Multi-threaded shell with matplotlib support."""
 
     def __init__(self,name,usage=None,rc=Struct(opts=None,args=None),
                  user_ns=None,user_global_ns=None, **kw):
         user_ns,b2 = self._matplotlib_config(name,user_ns)
         MTInteractiveShell.__init__(self,name,usage,rc,user_ns,user_global_ns,
                                     banner2=b2,**kw)
 
 #-----------------------------------------------------------------------------
 # Utility functions for the different GUI enabled IPShell* classes.
 
 def get_tk():
     """Tries to import Tkinter and returns a withdrawn Tkinter root
     window.  If Tkinter is already imported or not available, this
     returns None.  This function calls `hijack_tk` underneath.
     """
     if not USE_TK or sys.modules.has_key('Tkinter'):
         return None
     else:
         try:
             import Tkinter
         except ImportError:
             return None
         else:
             hijack_tk()
             r = Tkinter.Tk()
             r.withdraw()
             return r
 
 def hijack_tk():
     """Modifies Tkinter's mainloop with a dummy so when a module calls
     mainloop, it does not block.
 
     """
     def misc_mainloop(self, n=0):
         pass
     def tkinter_mainloop(n=0):
         pass
     
     import Tkinter
     Tkinter.Misc.mainloop = misc_mainloop
     Tkinter.mainloop = tkinter_mainloop
 
 def update_tk(tk):
     """Updates the Tkinter event loop.  This is typically called from
     the respective WX or GTK mainloops.
     """    
     if tk:
         tk.update()
 
 def hijack_wx():
     """Modifies wxPython's MainLoop with a dummy so user code does not
     block IPython.  The hijacked mainloop function is returned.
     """    
     def dummy_mainloop(*args, **kw):
         pass
 
     try:
         import wx
     except ImportError:
         # For very old versions of WX
         import wxPython as wx
         
     ver = wx.__version__
     orig_mainloop = None
     if ver[:3] >= '2.5':
         import wx
         if hasattr(wx, '_core_'): core = getattr(wx, '_core_')
         elif hasattr(wx, '_core'): core = getattr(wx, '_core')
         else: raise AttributeError('Could not find wx core module')
         orig_mainloop = core.PyApp_MainLoop
         core.PyApp_MainLoop = dummy_mainloop
     elif ver[:3] == '2.4':
         orig_mainloop = wx.wxc.wxPyApp_MainLoop
         wx.wxc.wxPyApp_MainLoop = dummy_mainloop
     else:
         warn("Unable to find either wxPython version 2.4 or >= 2.5.")
     return orig_mainloop
 
 def hijack_gtk():
     """Modifies pyGTK's mainloop with a dummy so user code does not
     block IPython.  This function returns the original `gtk.mainloop`
     function that has been hijacked.
     """    
     def dummy_mainloop(*args, **kw):
         pass
     import gtk
     if gtk.pygtk_version >= (2,4,0): orig_mainloop = gtk.main
     else:                            orig_mainloop = gtk.mainloop
     gtk.mainloop = dummy_mainloop
     gtk.main = dummy_mainloop
     return orig_mainloop
 
 #-----------------------------------------------------------------------------
 # The IPShell* classes below are the ones meant to be run by external code as
 # IPython instances.  Note that unless a specific threading strategy is
 # desired, the factory function start() below should be used instead (it
 # selects the proper threaded class).
 
 class IPThread(threading.Thread):
     def run(self):
         self.IP.mainloop(self._banner)
         self.IP.kill()
 
 class IPShellGTK(IPThread):
     """Run a gtk mainloop() in a separate thread.
     
     Python commands can be passed to the thread where they will be executed.
     This is implemented by periodically checking for passed code using a
     GTK timeout callback."""
     
     TIMEOUT = 100 # Millisecond interval between timeouts.
 
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,
                  debug=1,shell_class=MTInteractiveShell):
 
         import gtk
         
         self.gtk = gtk
         self.gtk_mainloop = hijack_gtk()
 
         # Allows us to use both Tk and GTK.
         self.tk = get_tk()
         
         if gtk.pygtk_version >= (2,4,0): mainquit = self.gtk.main_quit
         else:                            mainquit = self.gtk.mainquit
 
         self.IP = make_IPython(argv,user_ns=user_ns,
                                user_global_ns=user_global_ns,
                                debug=debug,
                                shell_class=shell_class,
                                on_kill=[mainquit])
 
         # HACK: slot for banner in self; it will be passed to the mainloop
         # method only and .run() needs it.  The actual value will be set by
         # .mainloop().
         self._banner = None 
 
         threading.Thread.__init__(self)
 
     def mainloop(self,sys_exit=0,banner=None):
 
         self._banner = banner
         
         if self.gtk.pygtk_version >= (2,4,0):
             import gobject
             gobject.idle_add(self.on_timer)
         else:
             self.gtk.idle_add(self.on_timer)
 
         if sys.platform != 'win32':
             try:
                 if self.gtk.gtk_version[0] >= 2:
                     self.gtk.gdk.threads_init()
             except AttributeError:
                 pass
             except RuntimeError:
                 error('Your pyGTK likely has not been compiled with '
                       'threading support.\n'
                       'The exception printout is below.\n'
                       'You can either rebuild pyGTK with threads, or '
                       'try using \n'
                       'matplotlib with a different backend (like Tk or WX).\n'
                       'Note that matplotlib will most likely not work in its '
                       'current state!')
                 self.IP.InteractiveTB()
 
         self.start()
         self.gtk.gdk.threads_enter()
         self.gtk_mainloop()
         self.gtk.gdk.threads_leave()
         self.join()
 
     def on_timer(self):
         """Called when GTK is idle.
 
         Must return True always, otherwise GTK stops calling it"""
         
         update_tk(self.tk)
         self.IP.runcode()
         time.sleep(0.01)
         return True
 
 
 class IPShellWX(IPThread):
     """Run a wx mainloop() in a separate thread.
     
     Python commands can be passed to the thread where they will be executed.
     This is implemented by periodically checking for passed code using a
     GTK timeout callback."""
     
     TIMEOUT = 100 # Millisecond interval between timeouts.
 
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,
                  debug=1,shell_class=MTInteractiveShell):
 
         self.IP = make_IPython(argv,user_ns=user_ns,
                                user_global_ns=user_global_ns,
                                debug=debug,
                                shell_class=shell_class,
                                on_kill=[self.wxexit])
 
         wantedwxversion=self.IP.rc.wxversion
         if wantedwxversion!="0":
             try:
                 import wxversion
             except ImportError:
                 error('The wxversion module is needed for WX version selection')
             else:
                 try:
                     wxversion.select(wantedwxversion)
                 except:
                     self.IP.InteractiveTB()
                     error('Requested wxPython version %s could not be loaded' %
                                                                wantedwxversion)
 
         import wx
 
         threading.Thread.__init__(self)
         self.wx = wx
         self.wx_mainloop = hijack_wx()
 
         # Allows us to use both Tk and GTK.
         self.tk = get_tk()
         
         # HACK: slot for banner in self; it will be passed to the mainloop
         # method only and .run() needs it.  The actual value will be set by
         # .mainloop().
         self._banner = None 
 
         self.app = None
 
     def wxexit(self, *args):
         if self.app is not None:
             self.app.agent.timer.Stop()
             self.app.ExitMainLoop()
 
     def mainloop(self,sys_exit=0,banner=None):
 
         self._banner = banner
         
         self.start()
 
         class TimerAgent(self.wx.MiniFrame):
             wx = self.wx
             IP = self.IP
             tk = self.tk
             def __init__(self, parent, interval):
                 style = self.wx.DEFAULT_FRAME_STYLE | self.wx.TINY_CAPTION_HORIZ
                 self.wx.MiniFrame.__init__(self, parent, -1, ' ', pos=(200, 200),
                                              size=(100, 100),style=style)
                 self.Show(False)
                 self.interval = interval
                 self.timerId = self.wx.NewId()                                
 
             def StartWork(self):
                 self.timer = self.wx.Timer(self, self.timerId)
                 self.wx.EVT_TIMER(self,  self.timerId, self.OnTimer)
                 self.timer.Start(self.interval)
 
             def OnTimer(self, event):
                 update_tk(self.tk)
                 self.IP.runcode()
 
         class App(self.wx.App):
             wx = self.wx
             TIMEOUT = self.TIMEOUT
             def OnInit(self):
                 'Create the main window and insert the custom frame'
                 self.agent = TimerAgent(None, self.TIMEOUT)
                 self.agent.Show(False)
                 self.agent.StartWork()
                 return True
 
         self.app = App(redirect=False)
         self.wx_mainloop(self.app)
         self.join()
 
 
 class IPShellQt(IPThread):
     """Run a Qt event loop in a separate thread.
     
     Python commands can be passed to the thread where they will be executed.
     This is implemented by periodically checking for passed code using a
     Qt timer / slot."""
     
     TIMEOUT = 100 # Millisecond interval between timeouts.
 
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,
                  debug=0,shell_class=MTInteractiveShell):
         
         import qt
 
         class newQApplication:
             def __init__( self ):
                 self.QApplication = qt.QApplication
                 
             def __call__( *args, **kwargs ):
                 return qt.qApp
 
             def exec_loop( *args, **kwargs ):
                 pass
 
             def __getattr__( self, name ):
                 return getattr( self.QApplication, name )
           
         qt.QApplication = newQApplication()
 
         # Allows us to use both Tk and QT.
         self.tk = get_tk()
 
         self.IP = make_IPython(argv,user_ns=user_ns,
                                user_global_ns=user_global_ns,
                                debug=debug,
                                shell_class=shell_class,
                                on_kill=[qt.qApp.exit])
 
         # HACK: slot for banner in self; it will be passed to the mainloop
         # method only and .run() needs it.  The actual value will be set by
         # .mainloop().
         self._banner = None 
         
         threading.Thread.__init__(self)
 
     def mainloop(self,sys_exit=0,banner=None):
 
         import qt
 
         self._banner = banner
 
         if qt.QApplication.startingUp():
           a = qt.QApplication.QApplication(sys.argv)
         self.timer = qt.QTimer()
         qt.QObject.connect( self.timer, qt.SIGNAL( 'timeout()' ), self.on_timer )
 
         self.start()
         self.timer.start( self.TIMEOUT, True )
         while True:
             if self.IP._kill: break
             qt.qApp.exec_loop()
         self.join()
 
     def on_timer(self):
         update_tk(self.tk)
         result = self.IP.runcode()
         self.timer.start( self.TIMEOUT, True )
         return result
 
 
 class IPShellQt4(IPThread):
     """Run a Qt event loop in a separate thread.
 
     Python commands can be passed to the thread where they will be executed.
     This is implemented by periodically checking for passed code using a
     Qt timer / slot."""
 
     TIMEOUT = 100 # Millisecond interval between timeouts.
 
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,
                  debug=0,shell_class=MTInteractiveShell):
 
         from PyQt4 import QtCore, QtGui
 
         class newQApplication:
             def __init__( self ):
                 self.QApplication = QtGui.QApplication
 
             def __call__( *args, **kwargs ):
                 return QtGui.qApp
 
             def exec_loop( *args, **kwargs ):
                 pass
 
             def __getattr__( self, name ):
                 return getattr( self.QApplication, name )
 
         QtGui.QApplication = newQApplication()
 
         # Allows us to use both Tk and QT.
         self.tk = get_tk()
 
         self.IP = make_IPython(argv,user_ns=user_ns,
                                user_global_ns=user_global_ns,
                                debug=debug,
                                shell_class=shell_class,
                                on_kill=[QtGui.qApp.exit])
 
         # HACK: slot for banner in self; it will be passed to the mainloop
         # method only and .run() needs it.  The actual value will be set by
         # .mainloop().
         self._banner = None
 
         threading.Thread.__init__(self)
 
     def mainloop(self,sys_exit=0,banner=None):
 
         from PyQt4 import QtCore, QtGui
 
         self._banner = banner
 
         if QtGui.QApplication.startingUp():
           a = QtGui.QApplication.QApplication(sys.argv)
         self.timer = QtCore.QTimer()
         QtCore.QObject.connect( self.timer, QtCore.SIGNAL( 'timeout()' ), self.on_timer )
 
         self.start()
         self.timer.start( self.TIMEOUT )
         while True:
             if self.IP._kill: break
             QtGui.qApp.exec_()
         self.join()
 
     def on_timer(self):
         update_tk(self.tk)
         result = self.IP.runcode()
         self.timer.start( self.TIMEOUT )
         return result
 
 
 # A set of matplotlib public IPython shell classes, for single-threaded (Tk*
 # and FLTK*) and multithreaded (GTK*, WX* and Qt*) backends to use.
 def _load_pylab(user_ns):
     """Allow users to disable pulling all of pylab into the top-level
     namespace.
 
     This little utility must be called AFTER the actual ipython instance is
     running, since only then will the options file have been fully parsed."""
     
     ip = IPython.ipapi.get()
     if ip.options.pylab_import_all:
         exec "from matplotlib.pylab import *" in user_ns
 
 class IPShellMatplotlib(IPShell):
     """Subclass IPShell with MatplotlibShell as the internal shell.
 
     Single-threaded class, meant for the Tk* and FLTK* backends.
 
     Having this on a separate class simplifies the external driver code."""
     
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,debug=1):
         IPShell.__init__(self,argv,user_ns,user_global_ns,debug,
                          shell_class=MatplotlibShell)
         _load_pylab(self.IP.user_ns)
 
 class IPShellMatplotlibGTK(IPShellGTK):
     """Subclass IPShellGTK with MatplotlibMTShell as the internal shell.
 
     Multi-threaded class, meant for the GTK* backends."""
     
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,debug=1):
         IPShellGTK.__init__(self,argv,user_ns,user_global_ns,debug,
                             shell_class=MatplotlibMTShell)
         _load_pylab(self.IP.user_ns)
 
 class IPShellMatplotlibWX(IPShellWX):
     """Subclass IPShellWX with MatplotlibMTShell as the internal shell.
 
     Multi-threaded class, meant for the WX* backends."""
     
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,debug=1):
         IPShellWX.__init__(self,argv,user_ns,user_global_ns,debug,
                            shell_class=MatplotlibMTShell)
         _load_pylab(self.IP.user_ns)
 
 class IPShellMatplotlibQt(IPShellQt):
     """Subclass IPShellQt with MatplotlibMTShell as the internal shell.
 
     Multi-threaded class, meant for the Qt* backends."""
     
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,debug=1):
         IPShellQt.__init__(self,argv,user_ns,user_global_ns,debug,
                            shell_class=MatplotlibMTShell)
         _load_pylab(self.IP.user_ns)
 
 class IPShellMatplotlibQt4(IPShellQt4):
     """Subclass IPShellQt4 with MatplotlibMTShell as the internal shell.
 
     Multi-threaded class, meant for the Qt4* backends."""
 
     def __init__(self,argv=None,user_ns=None,user_global_ns=None,debug=1):
         IPShellQt4.__init__(self,argv,user_ns,user_global_ns,debug,
                            shell_class=MatplotlibMTShell)
         _load_pylab(self.IP.user_ns)
 
 #-----------------------------------------------------------------------------
 # Factory functions to actually start the proper thread-aware shell
 
 def _matplotlib_shell_class():
     """Factory function to handle shell class selection for matplotlib.
 
     The proper shell class to use depends on the matplotlib backend, since
     each backend requires a different threading strategy."""
 
     try:
         import matplotlib
     except ImportError:
         error('matplotlib could NOT be imported!  Starting normal IPython.')
         sh_class = IPShell
     else:
         backend = matplotlib.rcParams['backend']
         if backend.startswith('GTK'):
             sh_class = IPShellMatplotlibGTK
         elif backend.startswith('WX'):
             sh_class = IPShellMatplotlibWX
         elif backend.startswith('Qt4'):
             sh_class = IPShellMatplotlibQt4
         elif backend.startswith('Qt'):
             sh_class = IPShellMatplotlibQt
         else:
             sh_class = IPShellMatplotlib
     #print 'Using %s with the %s backend.' % (sh_class,backend) # dbg
     return sh_class
 
 # This is the one which should be called by external code.
 def start(user_ns = None):
     """Return a running shell instance, dealing with threading options.
 
     This is a factory function which will instantiate the proper IPython shell
     based on the user's threading choice.  Such a selector is needed because
     different GUI toolkits require different thread handling details."""
 
     global USE_TK
     # Crude sys.argv hack to extract the threading options.
     argv = sys.argv
     if len(argv) > 1:
         if len(argv) > 2:
             arg2 = argv[2]
             if arg2.endswith('-tk'):
                 USE_TK = True
         arg1 = argv[1]
         if arg1.endswith('-gthread'):
             shell = IPShellGTK
         elif arg1.endswith( '-qthread' ):
             shell = IPShellQt
         elif arg1.endswith( '-q4thread' ):
             shell = IPShellQt4
         elif arg1.endswith('-wthread'):
             shell = IPShellWX
         elif arg1.endswith('-pylab'):
             shell = _matplotlib_shell_class()
         else:
             shell = IPShell
     else:
         shell = IPShell
     return shell(user_ns = user_ns)
 
 # Some aliases for backwards compatibility
 IPythonShell = IPShell
 IPythonShellEmbed = IPShellEmbed
 #************************ End of file <Shell.py> ***************************

IPython/genutils.py

@@ -1,1850 +1,1850 b''
 # -*- coding: utf-8 -*-
 """
 General purpose utilities.
 
 This is a grab-bag of stuff I find useful in most programs I write. Some of
 these things are also convenient when working at the command line.
 
-$Id: genutils.py 2568 2007-07-29 21:38:44Z fperez $"""
+$Id: genutils.py 2577 2007-08-02 23:50:02Z fperez $"""
 
 #*****************************************************************************
 #       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.
 #*****************************************************************************
 
 from IPython import Release
 __author__  = '%s <%s>' % Release.authors['Fernando']
 __license__ = Release.license
 
 #****************************************************************************
 # required modules from the Python standard library
 import __main__
 import commands
 import os
 import re
 import shlex
 import shutil
 import sys
 import tempfile
 import time
 import types
 import warnings
 
 # Other IPython utilities
 import IPython
 from IPython.Itpl import Itpl,itpl,printpl
 from IPython import DPyGetOpt, platutils
 from IPython.generics import result_display
 from path import path
 if os.name == "nt":
     from IPython.winconsole import get_console_size
 
 #****************************************************************************
 # Exceptions
 class Error(Exception):
     """Base class for exceptions in this module."""
     pass
 
 #----------------------------------------------------------------------------
 class IOStream:
     def __init__(self,stream,fallback):
         if not hasattr(stream,'write') or not hasattr(stream,'flush'):
             stream = fallback
         self.stream = stream
         self._swrite = stream.write
         self.flush = stream.flush
 
     def write(self,data):
         try:
             self._swrite(data)
         except:
             try:
                 # print handles some unicode issues which may trip a plain
                 # write() call.  Attempt to emulate write() by using a
                 # trailing comma
                 print >> self.stream, data,
             except:
                 # if we get here, something is seriously broken.
                 print >> sys.stderr, \
                       'ERROR - failed to write data to stream:', self.stream
 
     def close(self):
         pass
                 
         
 class IOTerm:
     """ Term holds the file or file-like objects for handling I/O operations.
 
     These are normally just sys.stdin, sys.stdout and sys.stderr but for
     Windows they can can replaced to allow editing the strings before they are
     displayed."""
 
     # In the future, having IPython channel all its I/O operations through
     # this class will make it easier to embed it into other environments which
     # are not a normal terminal (such as a GUI-based shell)
     def __init__(self,cin=None,cout=None,cerr=None):
         self.cin  = IOStream(cin,sys.stdin)
         self.cout = IOStream(cout,sys.stdout)
         self.cerr = IOStream(cerr,sys.stderr)
         
 # Global variable to be used for all I/O
 Term = IOTerm()
 
 import IPython.rlineimpl as readline
 # Remake Term to use the readline i/o facilities
 if sys.platform == 'win32' and readline.have_readline:
     
     Term = IOTerm(cout=readline._outputfile,cerr=readline._outputfile)
     
 
 #****************************************************************************
 # Generic warning/error printer, used by everything else
 def warn(msg,level=2,exit_val=1):
     """Standard warning printer. Gives formatting consistency.
 
     Output is sent to Term.cerr (sys.stderr by default).
     
     Options:
     
     -level(2): allows finer control:
       0 -> Do nothing, dummy function.
       1 -> Print message.
       2 -> Print 'WARNING:' + message. (Default level).
       3 -> Print 'ERROR:' + message.
       4 -> Print 'FATAL ERROR:' + message and trigger a sys.exit(exit_val).
 
     -exit_val (1): exit value returned by sys.exit() for a level 4
     warning. Ignored for all other levels."""
     
     if level>0:
         header = ['','','WARNING: ','ERROR: ','FATAL ERROR: ']
         print >> Term.cerr, '%s%s' % (header[level],msg)
         if level == 4:
             print >> Term.cerr,'Exiting.\n'
             sys.exit(exit_val)
 
 def info(msg):
     """Equivalent to warn(msg,level=1)."""
 
     warn(msg,level=1)
 
 def error(msg):
     """Equivalent to warn(msg,level=3)."""
 
     warn(msg,level=3)
 
 def fatal(msg,exit_val=1):
     """Equivalent to warn(msg,exit_val=exit_val,level=4)."""
 
     warn(msg,exit_val=exit_val,level=4)
 
 #---------------------------------------------------------------------------
 # Debugging routines
 # 
 def debugx(expr,pre_msg=''):
     """Print the value of an expression from the caller's frame.
     
     Takes an expression, evaluates it in the caller's frame and prints both
     the given expression and the resulting value (as well as a debug mark
     indicating the name of the calling function.  The input must be of a form
     suitable for eval().
 
     An optional message can be passed, which will be prepended to the printed
     expr->value pair."""
     
     cf = sys._getframe(1)
     print '[DBG:%s] %s%s -> %r' % (cf.f_code.co_name,pre_msg,expr,
                                    eval(expr,cf.f_globals,cf.f_locals))
 
 # deactivate it by uncommenting the following line, which makes it a no-op
 #def debugx(expr,pre_msg=''): pass
 
 #----------------------------------------------------------------------------
 StringTypes = types.StringTypes
 
 # Basic timing functionality
 
 # If possible (Unix), use the resource module instead of time.clock()
 try:
     import resource
     def clocku():
         """clocku() -> floating point number
 
         Return the *USER* CPU time in seconds since the start of the process.
         This is done via a call to resource.getrusage, so it avoids the
         wraparound problems in time.clock()."""
         
         return resource.getrusage(resource.RUSAGE_SELF)[0]
     
     def clocks():
         """clocks() -> floating point number
 
         Return the *SYSTEM* CPU time in seconds since the start of the process.
         This is done via a call to resource.getrusage, so it avoids the
         wraparound problems in time.clock()."""
         
         return resource.getrusage(resource.RUSAGE_SELF)[1]
     
     def clock():
         """clock() -> floating point number
 
         Return the *TOTAL USER+SYSTEM* CPU time in seconds since the start of
         the process.  This is done via a call to resource.getrusage, so it
         avoids the wraparound problems in time.clock()."""
 
         u,s = resource.getrusage(resource.RUSAGE_SELF)[:2] 
         return u+s
     
     def clock2():
         """clock2() -> (t_user,t_system)
 
         Similar to clock(), but return a tuple of user/system times."""
         return resource.getrusage(resource.RUSAGE_SELF)[:2]
 
 except ImportError:
     # There is no distinction of user/system time under windows, so we just use
     # time.clock() for everything...
     clocku = clocks = clock = time.clock
     def clock2():
         """Under windows, system CPU time can't be measured.
 
         This just returns clock() and zero."""
         return time.clock(),0.0
 
 def timings_out(reps,func,*args,**kw):
     """timings_out(reps,func,*args,**kw) -> (t_total,t_per_call,output)
 
     Execute a function reps times, return a tuple with the elapsed total
     CPU time in seconds, the time per call and the function's output.
 
     Under Unix, the return value is the sum of user+system time consumed by
     the process, computed via the resource module.  This prevents problems
     related to the wraparound effect which the time.clock() function has.
     
     Under Windows the return value is in wall clock seconds. See the
     documentation for the time module for more details."""
 
     reps = int(reps)
     assert reps >=1, 'reps must be >= 1'
     if reps==1:
         start = clock()
         out = func(*args,**kw)
         tot_time = clock()-start
     else:
         rng = xrange(reps-1) # the last time is executed separately to store output
         start = clock()
         for dummy in rng: func(*args,**kw)
         out = func(*args,**kw)  # one last time
         tot_time = clock()-start
     av_time = tot_time / reps
     return tot_time,av_time,out
 
 def timings(reps,func,*args,**kw):
     """timings(reps,func,*args,**kw) -> (t_total,t_per_call)
 
     Execute a function reps times, return a tuple with the elapsed total CPU
     time in seconds and the time per call. These are just the first two values
     in timings_out()."""
 
     return timings_out(reps,func,*args,**kw)[0:2]
 
 def timing(func,*args,**kw):
     """timing(func,*args,**kw) -> t_total
 
     Execute a function once, return the elapsed total CPU time in
     seconds. This is just the first value in timings_out()."""
 
     return timings_out(1,func,*args,**kw)[0]
 
 #****************************************************************************
 # file and system
 
 def arg_split(s,posix=False):
     """Split a command line's arguments in a shell-like manner.
 
     This is a modified version of the standard library's shlex.split()
     function, but with a default of posix=False for splitting, so that quotes
     in inputs are respected."""
 
     # XXX - there may be unicode-related problems here!!!  I'm not sure that
     # shlex is truly unicode-safe, so it might be necessary to do
     #
     # s = s.encode(sys.stdin.encoding)
     #
     # first, to ensure that shlex gets a normal string.  Input from anyone who
     # knows more about unicode and shlex than I would be good to have here...
     lex = shlex.shlex(s, posix=posix)
     lex.whitespace_split = True
     return list(lex)
 
 def system(cmd,verbose=0,debug=0,header=''):
     """Execute a system command, return its exit status.
 
     Options:
 
     - verbose (0): print the command to be executed.
     
     - debug (0): only print, do not actually execute.
 
     - header (''): Header to print on screen prior to the executed command (it
     is only prepended to the command, no newlines are added).
 
     Note: a stateful version of this function is available through the
     SystemExec class."""
 
     stat = 0
     if verbose or debug: print header+cmd
     sys.stdout.flush()
     if not debug: stat = os.system(cmd)
     return stat
 
 # This function is used by ipython in a lot of places to make system calls.
 # We need it to be slightly different under win32, due to the vagaries of
 # 'network shares'.  A win32 override is below.
 
 def shell(cmd,verbose=0,debug=0,header=''):
     """Execute a command in the system shell, always return None.
 
     Options:
 
     - verbose (0): print the command to be executed.
     
     - debug (0): only print, do not actually execute.
 
     - header (''): Header to print on screen prior to the executed command (it
     is only prepended to the command, no newlines are added).
 
     Note: this is similar to genutils.system(), but it returns None so it can
     be conveniently used in interactive loops without getting the return value
     (typically 0) printed many times."""
 
     stat = 0
     if verbose or debug: print header+cmd
     # flush stdout so we don't mangle python's buffering
     sys.stdout.flush()
     
     if not debug:
         platutils.set_term_title("IPy:" + cmd)
         os.system(cmd)
         platutils.set_term_title("IPy:" + os.path.basename(os.getcwd()))
 
 # override shell() for win32 to deal with network shares
 if os.name in ('nt','dos'):
 
     shell_ori = shell
 
     def shell(cmd,verbose=0,debug=0,header=''):
         if os.getcwd().startswith(r"\\"):
             path = os.getcwd()
             # change to c drive (cannot be on UNC-share when issuing os.system,
             # as cmd.exe cannot handle UNC addresses)
             os.chdir("c:")
             # issue pushd to the UNC-share and then run the command
             try:
                 shell_ori('"pushd %s&&"'%path+cmd,verbose,debug,header)
             finally:
                 os.chdir(path)
         else:
             shell_ori(cmd,verbose,debug,header)
 
     shell.__doc__ = shell_ori.__doc__
 
 def getoutput(cmd,verbose=0,debug=0,header='',split=0):
     """Dummy substitute for perl's backquotes.
 
     Executes a command and returns the output.
 
     Accepts the same arguments as system(), plus:
 
     - split(0): if true, the output is returned as a list split on newlines.
 
     Note: a stateful version of this function is available through the
     SystemExec class.
     
     This is pretty much deprecated and rarely used, 
     genutils.getoutputerror may be what you need.
     
     """
 
     if verbose or debug: print header+cmd
     if not debug:
         output = os.popen(cmd).read()
         # stipping last \n is here for backwards compat.
         if output.endswith('\n'):
             output = output[:-1]
         if split:
             return output.split('\n')
         else:
             return output
 
 def getoutputerror(cmd,verbose=0,debug=0,header='',split=0):
     """Return (standard output,standard error) of executing cmd in a shell.
 
     Accepts the same arguments as system(), plus:
 
     - split(0): if true, each of stdout/err is returned as a list split on
     newlines.
 
     Note: a stateful version of this function is available through the
     SystemExec class."""
 
     if verbose or debug: print header+cmd
     if not cmd:
         if split:
             return [],[]
         else:
             return '',''
     if not debug:
         pin,pout,perr = os.popen3(cmd)
         tout = pout.read().rstrip()
         terr = perr.read().rstrip()
         pin.close()
         pout.close()
         perr.close()
         if split:
             return tout.split('\n'),terr.split('\n')
         else:
             return tout,terr
 
 # for compatibility with older naming conventions
 xsys = system
 bq = getoutput
 
 class SystemExec:
     """Access the system and getoutput functions through a stateful interface.
 
     Note: here we refer to the system and getoutput functions from this
     library, not the ones from the standard python library.
     
     This class offers the system and getoutput functions as methods, but the
     verbose, debug and header parameters can be set for the instance (at
     creation time or later) so that they don't need to be specified on each
     call.
 
     For efficiency reasons, there's no way to override the parameters on a
     per-call basis other than by setting instance attributes. If you need
     local overrides, it's best to directly call system() or getoutput().
 
     The following names are provided as alternate options:
      - xsys: alias to system
      - bq: alias to getoutput
 
     An instance can then be created as:
      >>> sysexec = SystemExec(verbose=1,debug=0,header='Calling: ')
 
     And used as:
      >>> sysexec.xsys('pwd')
      >>> dirlist = sysexec.bq('ls -l')
     """
     
     def __init__(self,verbose=0,debug=0,header='',split=0):
         """Specify the instance's values for verbose, debug and header."""
         setattr_list(self,'verbose debug header split')
 
     def system(self,cmd):
         """Stateful interface to system(), with the same keyword parameters."""
 
         system(cmd,self.verbose,self.debug,self.header)
 
     def shell(self,cmd):
         """Stateful interface to shell(), with the same keyword parameters."""
 
         shell(cmd,self.verbose,self.debug,self.header)
 
     xsys = system  # alias
 
     def getoutput(self,cmd):
         """Stateful interface to getoutput()."""
 
         return getoutput(cmd,self.verbose,self.debug,self.header,self.split)
 
     def getoutputerror(self,cmd):
         """Stateful interface to getoutputerror()."""
 
         return getoutputerror(cmd,self.verbose,self.debug,self.header,self.split)
 
     bq = getoutput  # alias
 
 #-----------------------------------------------------------------------------
 def mutex_opts(dict,ex_op):
     """Check for presence of mutually exclusive keys in a dict.
 
     Call: mutex_opts(dict,[[op1a,op1b],[op2a,op2b]...]"""
     for op1,op2 in ex_op:
         if op1 in dict and op2 in dict:
             raise ValueError,'\n*** ERROR in Arguments *** '\
                   'Options '+op1+' and '+op2+' are mutually exclusive.'
 
 #-----------------------------------------------------------------------------
 def get_py_filename(name):
     """Return a valid python filename in the current directory.
 
     If the given name is not a file, it adds '.py' and searches again.
     Raises IOError with an informative message if the file isn't found."""
 
     name = os.path.expanduser(name)
     if not os.path.isfile(name) and not name.endswith('.py'):
         name += '.py'
     if os.path.isfile(name):
         return name
     else:
         raise IOError,'File `%s` not found.' % name
 
 #-----------------------------------------------------------------------------
 def filefind(fname,alt_dirs = None):
     """Return the given filename either in the current directory, if it
     exists, or in a specified list of directories.
 
     ~ expansion is done on all file and directory names.
 
     Upon an unsuccessful search, raise an IOError exception."""
 
     if alt_dirs is None:
         try:
             alt_dirs = get_home_dir()
         except HomeDirError:
             alt_dirs = os.getcwd()
     search = [fname] + list_strings(alt_dirs)
     search = map(os.path.expanduser,search)
     #print 'search list for',fname,'list:',search  # dbg
     fname = search[0]
     if os.path.isfile(fname):
         return fname
     for direc in search[1:]:
         testname = os.path.join(direc,fname)
         #print 'testname',testname  # dbg
         if os.path.isfile(testname):
             return testname
     raise IOError,'File' + `fname` + \
           ' not found in current or supplied directories:' + `alt_dirs`
 
 #----------------------------------------------------------------------------
 def file_read(filename):
     """Read a file and close it.  Returns the file source."""
     fobj = open(filename,'r');
     source = fobj.read();
     fobj.close()
     return source
 
 def file_readlines(filename):
     """Read a file and close it.  Returns the file source using readlines()."""
     fobj = open(filename,'r');
     lines = fobj.readlines();
     fobj.close()
     return lines
 
 #----------------------------------------------------------------------------
 def target_outdated(target,deps):
     """Determine whether a target is out of date.
 
     target_outdated(target,deps) -> 1/0
 
     deps: list of filenames which MUST exist.
     target: single filename which may or may not exist.
 
     If target doesn't exist or is older than any file listed in deps, return
     true, otherwise return false.
     """
     try:
         target_time = os.path.getmtime(target)
     except os.error:
         return 1
     for dep in deps:
         dep_time = os.path.getmtime(dep)
         if dep_time > target_time:
             #print "For target",target,"Dep failed:",dep # dbg
             #print "times (dep,tar):",dep_time,target_time # dbg
             return 1
     return 0
 
 #-----------------------------------------------------------------------------
 def target_update(target,deps,cmd):
     """Update a target with a given command given a list of dependencies.
 
     target_update(target,deps,cmd) -> runs cmd if target is outdated.
 
     This is just a wrapper around target_outdated() which calls the given
     command if target is outdated."""
 
     if target_outdated(target,deps):
         xsys(cmd)
 
 #----------------------------------------------------------------------------
 def unquote_ends(istr):
     """Remove a single pair of quotes from the endpoints of a string."""
 
     if not istr:
         return istr
     if (istr[0]=="'" and istr[-1]=="'") or \
        (istr[0]=='"' and istr[-1]=='"'):
         return istr[1:-1]
     else:
         return istr
 
 #----------------------------------------------------------------------------
 def process_cmdline(argv,names=[],defaults={},usage=''):
     """ Process command-line options and arguments.
 
     Arguments:
 
     - argv: list of arguments, typically sys.argv.
     
     - names: list of option names. See DPyGetOpt docs for details on options
     syntax.
 
     - defaults: dict of default values.
 
     - usage: optional usage notice to print if a wrong argument is passed.
 
     Return a dict of options and a list of free arguments."""
 
     getopt = DPyGetOpt.DPyGetOpt()
     getopt.setIgnoreCase(0)
     getopt.parseConfiguration(names)
 
     try:
         getopt.processArguments(argv)
     except:
         print usage
         warn(`sys.exc_value`,level=4)
 
     defaults.update(getopt.optionValues)
     args = getopt.freeValues
     
     return defaults,args
 
 #----------------------------------------------------------------------------
 def optstr2types(ostr):
     """Convert a string of option names to a dict of type mappings.
 
     optstr2types(str) -> {None:'string_opts',int:'int_opts',float:'float_opts'}
 
     This is used to get the types of all the options in a string formatted
     with the conventions of DPyGetOpt. The 'type' None is used for options
     which are strings (they need no further conversion). This function's main
     use is to get a typemap for use with read_dict().
     """
 
     typeconv = {None:'',int:'',float:''}
     typemap = {'s':None,'i':int,'f':float}
     opt_re = re.compile(r'([\w]*)([^:=]*:?=?)([sif]?)')
 
     for w in ostr.split():
         oname,alias,otype = opt_re.match(w).groups()
         if otype == '' or alias == '!':   # simple switches are integers too
             otype = 'i'
         typeconv[typemap[otype]] += oname + ' '
     return typeconv
 
 #----------------------------------------------------------------------------
 def read_dict(filename,type_conv=None,**opt):
 
     """Read a dictionary of key=value pairs from an input file, optionally
     performing conversions on the resulting values.
 
     read_dict(filename,type_conv,**opt) -> dict
 
     Only one value per line is accepted, the format should be
      # optional comments are ignored
      key value\n
 
     Args:
 
       - type_conv: A dictionary specifying which keys need to be converted to
       which types. By default all keys are read as strings. This dictionary
       should have as its keys valid conversion functions for strings
       (int,long,float,complex, or your own).  The value for each key
       (converter) should be a whitespace separated string containing the names
       of all the entries in the file to be converted using that function. For
       keys to be left alone, use None as the conversion function (only needed
       with purge=1, see below).
 
       - opt: dictionary with extra options as below (default in parens)
 
         purge(0): if set to 1, all keys *not* listed in type_conv are purged out
         of the dictionary to be returned. If purge is going to be used, the
         set of keys to be left as strings also has to be explicitly specified
         using the (non-existent) conversion function None.
 
         fs(None): field separator. This is the key/value separator to be used
         when parsing the file. The None default means any whitespace [behavior
         of string.split()].
 
         strip(0): if 1, strip string values of leading/trailinig whitespace.
 
         warn(1): warning level if requested keys are not found in file.
           - 0: silently ignore.
           - 1: inform but proceed.
           - 2: raise KeyError exception.
 
         no_empty(0): if 1, remove keys with whitespace strings as a value.
 
         unique([]): list of keys (or space separated string) which can't be
         repeated. If one such key is found in the file, each new instance
         overwrites the previous one. For keys not listed here, the behavior is
         to make a list of all appearances.
 
     Example:
     If the input file test.ini has:
       i 3
       x 4.5
       y 5.5
       s hi ho
     Then:
 
     >>> type_conv={int:'i',float:'x',None:'s'}
     >>> read_dict('test.ini')
     {'i': '3', 's': 'hi ho', 'x': '4.5', 'y': '5.5'}
     >>> read_dict('test.ini',type_conv)
     {'i': 3, 's': 'hi ho', 'x': 4.5, 'y': '5.5'}
     >>> read_dict('test.ini',type_conv,purge=1)
     {'i': 3, 's': 'hi ho', 'x': 4.5}
     """
 
     # starting config
     opt.setdefault('purge',0)
     opt.setdefault('fs',None)  # field sep defaults to any whitespace
     opt.setdefault('strip',0)
     opt.setdefault('warn',1)
     opt.setdefault('no_empty',0)
     opt.setdefault('unique','')
     if type(opt['unique']) in StringTypes:
         unique_keys = qw(opt['unique'])
     elif type(opt['unique']) in (types.TupleType,types.ListType):
         unique_keys = opt['unique']
     else:
         raise ValueError, 'Unique keys must be given as a string, List or Tuple'
 
     dict = {}
     # first read in table of values as strings
     file = open(filename,'r')
     for line in file.readlines():
         line = line.strip()
         if len(line) and line[0]=='#': continue
         if len(line)>0:
             lsplit = line.split(opt['fs'],1)
             try:
                 key,val = lsplit
             except ValueError:
                 key,val = lsplit[0],''
             key = key.strip()
             if opt['strip']: val = val.strip()
             if val == "''" or val == '""': val = ''
             if opt['no_empty'] and (val=='' or val.isspace()):
                 continue
             # if a key is found more than once in the file, build a list
             # unless it's in the 'unique' list. In that case, last found in file
             # takes precedence. User beware.
             try:
                 if dict[key] and key in unique_keys:
                     dict[key] = val
                 elif type(dict[key]) is types.ListType:
                     dict[key].append(val)
                 else:
                     dict[key] = [dict[key],val]
             except KeyError:
                 dict[key] = val
     # purge if requested
     if opt['purge']:
         accepted_keys = qwflat(type_conv.values())
         for key in dict.keys():
             if key in accepted_keys: continue
             del(dict[key])
     # now convert if requested
     if type_conv==None: return dict
     conversions = type_conv.keys()
     try: conversions.remove(None)
     except: pass
     for convert in conversions:
         for val in qw(type_conv[convert]):
             try:
                 dict[val] = convert(dict[val])
             except KeyError,e:
                 if opt['warn'] == 0:
                     pass
                 elif opt['warn'] == 1:
                     print >>sys.stderr, 'Warning: key',val,\
                           'not found in file',filename
                 elif opt['warn'] == 2:
                     raise KeyError,e
                 else:
                     raise ValueError,'Warning level must be 0,1 or 2'
 
     return dict
 
 #----------------------------------------------------------------------------
 def flag_calls(func):
     """Wrap a function to detect and flag when it gets called.
 
     This is a decorator which takes a function and wraps it in a function with
     a 'called' attribute. wrapper.called is initialized to False.
 
     The wrapper.called attribute is set to False right before each call to the
     wrapped function, so if the call fails it remains False.  After the call
     completes, wrapper.called is set to True and the output is returned.
 
     Testing for truth in wrapper.called allows you to determine if a call to
     func() was attempted and succeeded."""
     
     def wrapper(*args,**kw):
         wrapper.called = False
         out = func(*args,**kw)
         wrapper.called = True
         return out
 
     wrapper.called = False
     wrapper.__doc__ = func.__doc__
     return wrapper
 
 #----------------------------------------------------------------------------
 class HomeDirError(Error):
     pass
 
 def get_home_dir():
     """Return the closest possible equivalent to a 'home' directory.
 
     We first try $HOME.  Absent that, on NT it's $HOMEDRIVE\$HOMEPATH.
 
     Currently only Posix and NT are implemented, a HomeDirError exception is
     raised for all other OSes. """
 
     isdir = os.path.isdir
     env = os.environ
     
     # first, check py2exe distribution root directory for _ipython.
     # This overrides all. Normally does not exist.
     
     if '\\library.zip\\' in IPython.__file__.lower():
         root, rest = IPython.__file__.lower().split('library.zip')
         if isdir(root + '_ipython'):
             os.environ["IPYKITROOT"] = root.rstrip('\\')
             return root
     
     try:
         homedir = env['HOME']
         if not isdir(homedir):
             # in case a user stuck some string which does NOT resolve to a
             # valid path, it's as good as if we hadn't foud it
             raise KeyError
         return homedir
     except KeyError:
         if os.name == 'posix':
             raise HomeDirError,'undefined $HOME, IPython can not proceed.'
         elif os.name == 'nt':
             # For some strange reason, win9x returns 'nt' for os.name.
             try:
                 homedir = os.path.join(env['HOMEDRIVE'],env['HOMEPATH'])
                 if not isdir(homedir):
                     homedir = os.path.join(env['USERPROFILE'])
                     if not isdir(homedir):
                         raise HomeDirError
                 return homedir
             except:
                 try:
                     # Use the registry to get the 'My Documents' folder.
                     import _winreg as wreg
                     key = wreg.OpenKey(wreg.HKEY_CURRENT_USER,
                                        "Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders")
                     homedir = wreg.QueryValueEx(key,'Personal')[0]
                     key.Close()
                     if not isdir(homedir):
                         e = ('Invalid "Personal" folder registry key '
                              'typically "My Documents".\n'
                              'Value: %s\n'
                              'This is not a valid directory on your system.' %
                              homedir)
                         raise HomeDirError(e)
                     return homedir
                 except HomeDirError:
                     raise
                 except:
                     return 'C:\\'
         elif os.name == 'dos':
             # Desperate, may do absurd things in classic MacOS. May work under DOS.
             return 'C:\\'
         else:
             raise HomeDirError,'support for your operating system not implemented.'
 
 #****************************************************************************
 # strings and text
 
 class LSString(str):
     """String derivative with a special access attributes.
 
     These are normal strings, but with the special attributes:
 
         .l (or .list) : value as list (split on newlines).
         .n (or .nlstr): original value (the string itself).
         .s (or .spstr): value as whitespace-separated string.
         .p (or .paths): list of path objects
         
     Any values which require transformations are computed only once and
     cached.
 
     Such strings are very useful to efficiently interact with the shell, which
     typically only understands whitespace-separated options for commands."""
 
     def get_list(self):
         try:
             return self.__list
         except AttributeError:
             self.__list = self.split('\n')
             return self.__list
 
     l = list = property(get_list)
 
     def get_spstr(self):
         try:
             return self.__spstr
         except AttributeError:
             self.__spstr = self.replace('\n',' ')
             return self.__spstr
 
     s = spstr = property(get_spstr)
 
     def get_nlstr(self):
         return self
 
     n = nlstr = property(get_nlstr)
 
     def get_paths(self):
         try:
             return self.__paths
         except AttributeError:
             self.__paths = [path(p) for p in self.split('\n') if os.path.exists(p)]
             return self.__paths
     
     p = paths = property(get_paths)
 
 def print_lsstring(arg):
     """ Prettier (non-repr-like) and more informative printer for LSString """
     print "LSString (.p, .n, .l, .s available). Value:"
     print arg
     
 print_lsstring = result_display.when_type(LSString)(print_lsstring)
 
 #----------------------------------------------------------------------------
 class SList(list):
     """List derivative with a special access attributes.
 
     These are normal lists, but with the special attributes:
 
         .l (or .list) : value as list (the list itself).
         .n (or .nlstr): value as a string, joined on newlines.
         .s (or .spstr): value as a string, joined on spaces.
         .p (or .paths): list of path objects
         
     Any values which require transformations are computed only once and
     cached."""
 
     def get_list(self):
         return self
 
     l = list = property(get_list)
 
     def get_spstr(self):
         try:
             return self.__spstr
         except AttributeError:
             self.__spstr = ' '.join(self)
             return self.__spstr
 
     s = spstr = property(get_spstr)
 
     def get_nlstr(self):
         try:
             return self.__nlstr
         except AttributeError:
             self.__nlstr = '\n'.join(self)
             return self.__nlstr
 
     n = nlstr = property(get_nlstr)
     
     def get_paths(self):
         try:
             return self.__paths
         except AttributeError:
             self.__paths = [path(p) for p in self if os.path.exists(p)]
             return self.__paths
     
     p = paths = property(get_paths)
 
 #----------------------------------------------------------------------------
 def esc_quotes(strng):
     """Return the input string with single and double quotes escaped out"""
 
     return strng.replace('"','\\"').replace("'","\\'")
 
 #----------------------------------------------------------------------------
 def make_quoted_expr(s):
     """Return string s in appropriate quotes, using raw string if possible.
     
     Effectively this turns string: cd \ao\ao\
     to: r"cd \ao\ao\_"[:-1]
     
     Note the use of raw string and padding at the end to allow trailing backslash.
     
     """
     
     tail = ''
     tailpadding = ''
     raw  = ''
     if "\\" in s:
         raw = 'r'
         if s.endswith('\\'):
             tail = '[:-1]'
             tailpadding = '_'
     if '"' not in s:
         quote = '"'
     elif "'" not in s:
         quote = "'"
     elif '"""' not in s and not s.endswith('"'):
         quote = '"""'
     elif "'''" not in s and not s.endswith("'"):
         quote = "'''"
     else:
         # give up, backslash-escaped string will do
         return '"%s"' % esc_quotes(s)
     res = itpl("$raw$quote$s$tailpadding$quote$tail")
     return res
 
 
 #----------------------------------------------------------------------------
 def raw_input_multi(header='', ps1='==> ', ps2='..> ',terminate_str = '.'):
     """Take multiple lines of input.
 
     A list with each line of input as a separate element is returned when a
     termination string is entered (defaults to a single '.'). Input can also
     terminate via EOF (^D in Unix, ^Z-RET in Windows).
 
     Lines of input which end in \\ are joined into single entries (and a
     secondary continuation prompt is issued as long as the user terminates
     lines with \\). This allows entering very long strings which are still
     meant to be treated as single entities.
     """
 
     try:
         if header:
             header += '\n'
         lines = [raw_input(header + ps1)]
     except EOFError:
         return []
     terminate = [terminate_str]
     try:
         while lines[-1:] != terminate:
             new_line = raw_input(ps1)
             while new_line.endswith('\\'):
                 new_line = new_line[:-1] + raw_input(ps2)
             lines.append(new_line)
                 
         return lines[:-1]  # don't return the termination command
     except EOFError:
         print
         return lines
 
 #----------------------------------------------------------------------------
 def raw_input_ext(prompt='',  ps2='... '):
     """Similar to raw_input(), but accepts extended lines if input ends with \\."""
 
     line = raw_input(prompt)
     while line.endswith('\\'):
         line = line[:-1] + raw_input(ps2)
     return line
 
 #----------------------------------------------------------------------------
 def ask_yes_no(prompt,default=None):
-    """Asks a question and returns an integer 1/0 (y/n) answer.
+    """Asks a question and returns a boolean (y/n) answer.
 
     If default is given (one of 'y','n'), it is used if the user input is
     empty. Otherwise the question is repeated until an answer is given.
 
     An EOF is treated as the default answer.  If there is no default, an
     exception is raised to prevent infinite loops.
 
     Valid answers are: y/yes/n/no (match is not case sensitive)."""
 
     answers = {'y':True,'n':False,'yes':True,'no':False}
     ans = None
     while ans not in answers.keys():
         try:
             ans = raw_input(prompt+' ').lower()
             if not ans:  # response was an empty string
                 ans = default
         except KeyboardInterrupt:
             pass
         except EOFError:
             if default in answers.keys():
                 ans = default
                 print
             else:
                 raise
             
     return answers[ans]
 
 #----------------------------------------------------------------------------
 def marquee(txt='',width=78,mark='*'):
     """Return the input string centered in a 'marquee'."""
     if not txt:
         return (mark*width)[:width]
     nmark = (width-len(txt)-2)/len(mark)/2
     if nmark < 0: nmark =0
     marks = mark*nmark
     return '%s %s %s' % (marks,txt,marks)
 
 #----------------------------------------------------------------------------
 class EvalDict:
     """
     Emulate a dict which evaluates its contents in the caller's frame.
 
     Usage:
     >>>number = 19
     >>>text = "python"
     >>>print "%(text.capitalize())s %(number/9.0).1f rules!" % EvalDict()
     """
 
     # This version is due to [e-mail] on c.l.py, and is basically a
     # modified (shorter) version of:
     # http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/66018 by
     # Skip Montanaro ([e-mail]).
 
     def __getitem__(self, name):
         frame = sys._getframe(1)
         return eval(name, frame.f_globals, frame.f_locals)
 
 EvalString = EvalDict  # for backwards compatibility
 #----------------------------------------------------------------------------
 def qw(words,flat=0,sep=None,maxsplit=-1):
     """Similar to Perl's qw() operator, but with some more options.
 
     qw(words,flat=0,sep=' ',maxsplit=-1) -> words.split(sep,maxsplit)
 
     words can also be a list itself, and with flat=1, the output will be
     recursively flattened. Examples:
 
     >>> qw('1 2')
     ['1', '2']
     >>> qw(['a b','1 2',['m n','p q']])
     [['a', 'b'], ['1', '2'], [['m', 'n'], ['p', 'q']]]
     >>> qw(['a b','1 2',['m n','p q']],flat=1)
     ['a', 'b', '1', '2', 'm', 'n', 'p', 'q']    """
 
     if type(words) in StringTypes:
         return [word.strip() for word in words.split(sep,maxsplit)
                 if word and not word.isspace() ]
     if flat:
         return flatten(map(qw,words,[1]*len(words)))
     return map(qw,words)
 
 #----------------------------------------------------------------------------
 def qwflat(words,sep=None,maxsplit=-1):
     """Calls qw(words) in flat mode. It's just a convenient shorthand."""
     return qw(words,1,sep,maxsplit)
 
 #----------------------------------------------------------------------------
 def qw_lol(indata):
     """qw_lol('a b') -> [['a','b']],
     otherwise it's just a call to qw().
 
     We need this to make sure the modules_some keys *always* end up as a
     list of lists."""
 
     if type(indata) in StringTypes:
         return [qw(indata)]
     else:
         return qw(indata)
 
 #-----------------------------------------------------------------------------
 def list_strings(arg):
     """Always return a list of strings, given a string or list of strings
     as input."""
 
     if type(arg) in StringTypes: return [arg]
     else: return arg
 
 #----------------------------------------------------------------------------
 def grep(pat,list,case=1):
     """Simple minded grep-like function.
     grep(pat,list) returns occurrences of pat in list, None on failure.
 
     It only does simple string matching, with no support for regexps. Use the
     option case=0 for case-insensitive matching."""
 
     # This is pretty crude. At least it should implement copying only references
     # to the original data in case it's big. Now it copies the data for output.
     out=[]
     if case:
         for term in list:
             if term.find(pat)>-1: out.append(term)
     else:
         lpat=pat.lower()
         for term in list:
             if term.lower().find(lpat)>-1: out.append(term)
 
     if len(out): return out
     else: return None
 
 #----------------------------------------------------------------------------
 def dgrep(pat,*opts):
     """Return grep() on dir()+dir(__builtins__).
 
     A very common use of grep() when working interactively."""
 
     return grep(pat,dir(__main__)+dir(__main__.__builtins__),*opts)
 
 #----------------------------------------------------------------------------
 def idgrep(pat):
     """Case-insensitive dgrep()"""
 
     return dgrep(pat,0)
 
 #----------------------------------------------------------------------------
 def igrep(pat,list):
     """Synonym for case-insensitive grep."""
 
     return grep(pat,list,case=0)
 
 #----------------------------------------------------------------------------
 def indent(str,nspaces=4,ntabs=0):
     """Indent a string a given number of spaces or tabstops.
     
     indent(str,nspaces=4,ntabs=0) -> indent str by ntabs+nspaces.
     """
     if str is None:
         return
     ind = '\t'*ntabs+' '*nspaces
     outstr = '%s%s' % (ind,str.replace(os.linesep,os.linesep+ind))
     if outstr.endswith(os.linesep+ind):
         return outstr[:-len(ind)]
     else:
         return outstr
     
 #-----------------------------------------------------------------------------
 def native_line_ends(filename,backup=1):
     """Convert (in-place) a file to line-ends native to the current OS.
 
     If the optional backup argument is given as false, no backup of the
     original file is left.  """
 
     backup_suffixes = {'posix':'~','dos':'.bak','nt':'.bak','mac':'.bak'}
 
     bak_filename = filename + backup_suffixes[os.name]
 
     original = open(filename).read()
     shutil.copy2(filename,bak_filename)
     try:
         new = open(filename,'wb')
         new.write(os.linesep.join(original.splitlines()))
         new.write(os.linesep) # ALWAYS put an eol at the end of the file
         new.close()
     except:
         os.rename(bak_filename,filename)
     if not backup:
         try:
             os.remove(bak_filename)
         except:
             pass
     
 #----------------------------------------------------------------------------
 def get_pager_cmd(pager_cmd = None):
     """Return a pager command.
 
     Makes some attempts at finding an OS-correct one."""
     
     if os.name == 'posix':
         default_pager_cmd = 'less -r'  # -r for color control sequences
     elif os.name in ['nt','dos']:
         default_pager_cmd = 'type'
 
     if pager_cmd is None:
         try:
             pager_cmd = os.environ['PAGER']
         except:
             pager_cmd = default_pager_cmd
     return pager_cmd
 
 #-----------------------------------------------------------------------------
 def get_pager_start(pager,start):
     """Return the string for paging files with an offset.
 
     This is the '+N' argument which less and more (under Unix) accept.
     """
 
     if pager in ['less','more']:
         if start:
             start_string = '+' + str(start)
         else:
             start_string = ''
     else:
         start_string = ''
     return start_string
 
 #----------------------------------------------------------------------------
 # (X)emacs on W32 doesn't like to be bypassed with msvcrt.getch()
 if os.name == 'nt' and os.environ.get('TERM','dumb') != 'emacs':
     import msvcrt
     def page_more():
         """ Smart pausing between pages
 
         @return:    True if need print more lines, False if quit
         """
         Term.cout.write('---Return to continue, q to quit--- ')
         ans = msvcrt.getch()
         if ans in ("q", "Q"):
             result = False
         else:
             result = True
         Term.cout.write("\b"*37 + " "*37 + "\b"*37)
         return result
 else:
     def page_more():
         ans = raw_input('---Return to continue, q to quit--- ')
         if ans.lower().startswith('q'):
             return False
         else:
             return True
 
 esc_re = re.compile(r"(\x1b[^m]+m)")
 
 def page_dumb(strng,start=0,screen_lines=25):
     """Very dumb 'pager' in Python, for when nothing else works.
 
     Only moves forward, same interface as page(), except for pager_cmd and
     mode."""
 
     out_ln  = strng.splitlines()[start:]
     screens = chop(out_ln,screen_lines-1)
     if len(screens) == 1:
         print >>Term.cout, os.linesep.join(screens[0])
     else:
         last_escape = ""
         for scr in screens[0:-1]:
             hunk = os.linesep.join(scr)
             print >>Term.cout, last_escape + hunk
             if not page_more():
                 return
             esc_list = esc_re.findall(hunk)
             if len(esc_list) > 0:
                 last_escape = esc_list[-1]
         print >>Term.cout, last_escape + os.linesep.join(screens[-1])
 
 #----------------------------------------------------------------------------
 def page(strng,start=0,screen_lines=0,pager_cmd = None):
     """Print a string, piping through a pager after a certain length.
 
     The screen_lines parameter specifies the number of *usable* lines of your
     terminal screen (total lines minus lines you need to reserve to show other
     information).
 
     If you set screen_lines to a number <=0, page() will try to auto-determine
     your screen size and will only use up to (screen_size+screen_lines) for
     printing, paging after that. That is, if you want auto-detection but need
     to reserve the bottom 3 lines of the screen, use screen_lines = -3, and for
     auto-detection without any lines reserved simply use screen_lines = 0.
 
     If a string won't fit in the allowed lines, it is sent through the
     specified pager command. If none given, look for PAGER in the environment,
     and ultimately default to less.
 
     If no system pager works, the string is sent through a 'dumb pager'
     written in python, very simplistic.
     """
     
     # Ugly kludge, but calling curses.initscr() flat out crashes in emacs
     TERM = os.environ.get('TERM','dumb')
     if TERM in ['dumb','emacs'] and os.name != 'nt':
         print strng
         return
     # chop off the topmost part of the string we don't want to see
     str_lines = strng.split(os.linesep)[start:]
     str_toprint = os.linesep.join(str_lines)
     num_newlines = len(str_lines)
     len_str = len(str_toprint)
     
     # Dumb heuristics to guesstimate number of on-screen lines the string
     # takes.  Very basic, but good enough for docstrings in reasonable
     # terminals. If someone later feels like refining it, it's not hard.
     numlines = max(num_newlines,int(len_str/80)+1)
 
     if os.name == "nt":
         screen_lines_def = get_console_size(defaulty=25)[1]
     else:
         screen_lines_def = 25 # default value if we can't auto-determine
 
     # auto-determine screen size
     if screen_lines <= 0:
         if TERM=='xterm':
             try:
                 import curses
                 if hasattr(curses,'initscr'):
                     use_curses = 1
                 else:
                     use_curses = 0
             except ImportError:
                 use_curses = 0
         else:
             # curses causes problems on many terminals other than xterm.
             use_curses = 0
         if use_curses:
                 scr = curses.initscr()
                 screen_lines_real,screen_cols = scr.getmaxyx()
                 curses.endwin()
                 screen_lines += screen_lines_real
                 #print '***Screen size:',screen_lines_real,'lines x',\
                 #screen_cols,'columns.' # dbg
         else:
                 screen_lines += screen_lines_def
 
     #print 'numlines',numlines,'screenlines',screen_lines  # dbg
     if numlines <= screen_lines :
         #print '*** normal print'  # dbg
         print >>Term.cout, str_toprint
     else:
         # Try to open pager and default to internal one if that fails.
         # All failure modes are tagged as 'retval=1', to match the return
         # value of a failed system command.  If any intermediate attempt
         # sets retval to 1, at the end we resort to our own page_dumb() pager.
         pager_cmd = get_pager_cmd(pager_cmd)
         pager_cmd += ' ' + get_pager_start(pager_cmd,start)
         if os.name == 'nt':
             if pager_cmd.startswith('type'):
                 # The default WinXP 'type' command is failing on complex strings.
                 retval = 1
             else:
                 tmpname = tempfile.mktemp('.txt')
                 tmpfile = file(tmpname,'wt')
                 tmpfile.write(strng)
                 tmpfile.close()
                 cmd = "%s < %s" % (pager_cmd,tmpname)
                 if os.system(cmd):
                   retval = 1
                 else:
                   retval = None
                 os.remove(tmpname)
         else:
             try:
                 retval = None
                 # if I use popen4, things hang. No idea why.
                 #pager,shell_out = os.popen4(pager_cmd)
                 pager = os.popen(pager_cmd,'w')
                 pager.write(strng)
                 pager.close()
                 retval = pager.close()  # success returns None
             except IOError,msg:  # broken pipe when user quits
                 if msg.args == (32,'Broken pipe'):
                     retval = None
                 else:
                     retval = 1
             except OSError:
                 # Other strange problems, sometimes seen in Win2k/cygwin
                 retval = 1
         if retval is not None:
             page_dumb(strng,screen_lines=screen_lines)
 
 #----------------------------------------------------------------------------
 def page_file(fname,start = 0, pager_cmd = None):
     """Page a file, using an optional pager command and starting line.
     """
 
     pager_cmd = get_pager_cmd(pager_cmd)
     pager_cmd += ' ' + get_pager_start(pager_cmd,start)
 
     try:
         if os.environ['TERM'] in ['emacs','dumb']:
             raise EnvironmentError
         xsys(pager_cmd + ' ' + fname)
     except:
         try:
             if start > 0:
                 start -= 1
             page(open(fname).read(),start)
         except:
             print 'Unable to show file',`fname`
 
 #----------------------------------------------------------------------------
 def snip_print(str,width = 75,print_full = 0,header = ''):
     """Print a string snipping the midsection to fit in width.
 
     print_full: mode control:
       - 0: only snip long strings
       - 1: send to page() directly.
       - 2: snip long strings and ask for full length viewing with page()
     Return 1 if snipping was necessary, 0 otherwise."""
 
     if print_full == 1:
         page(header+str)
         return 0
 
     print header,
     if len(str) < width:
         print str
         snip = 0
     else:
         whalf = int((width -5)/2)
         print str[:whalf] + ' <...> ' + str[-whalf:]
         snip = 1
     if snip and print_full == 2:
         if raw_input(header+' Snipped. View (y/n)? [N]').lower() == 'y':
             page(str)
     return snip
 
 #****************************************************************************
 # lists, dicts and structures
 
 def belong(candidates,checklist):
     """Check whether a list of items appear in a given list of options.
 
     Returns a list of 1 and 0, one for each candidate given."""
 
     return [x in checklist for x in candidates]
 
 #----------------------------------------------------------------------------
 def uniq_stable(elems):
     """uniq_stable(elems) -> list
 
     Return from an iterable, a list of all the unique elements in the input,
     but maintaining the order in which they first appear.
 
     A naive solution to this problem which just makes a dictionary with the
     elements as keys fails to respect the stability condition, since
     dictionaries are unsorted by nature.
 
     Note: All elements in the input must be valid dictionary keys for this
     routine to work, as it internally uses a dictionary for efficiency
     reasons."""
     
     unique = []
     unique_dict = {}
     for nn in elems:
         if nn not in unique_dict:
             unique.append(nn)
             unique_dict[nn] = None
     return unique
 
 #----------------------------------------------------------------------------
 class NLprinter:
     """Print an arbitrarily nested list, indicating index numbers.
 
     An instance of this class called nlprint is available and callable as a
     function.
     
     nlprint(list,indent=' ',sep=': ') -> prints indenting each level by 'indent'
     and using 'sep' to separate the index from the value. """
 
     def __init__(self):
         self.depth = 0
     
     def __call__(self,lst,pos='',**kw):
         """Prints the nested list numbering levels."""
         kw.setdefault('indent',' ')
         kw.setdefault('sep',': ')
         kw.setdefault('start',0)
         kw.setdefault('stop',len(lst))
         # we need to remove start and stop from kw so they don't propagate
         # into a recursive call for a nested list.
         start = kw['start']; del kw['start']
         stop = kw['stop']; del kw['stop']
         if self.depth == 0 and 'header' in kw.keys():
             print kw['header']
             
         for idx in range(start,stop):
             elem = lst[idx]
             if type(elem)==type([]):
                 self.depth += 1
                 self.__call__(elem,itpl('$pos$idx,'),**kw)
                 self.depth -= 1
             else:
                 printpl(kw['indent']*self.depth+'$pos$idx$kw["sep"]$elem')
 
 nlprint = NLprinter()
 #----------------------------------------------------------------------------
 def all_belong(candidates,checklist):
     """Check whether a list of items ALL appear in a given list of options.
 
     Returns a single 1 or 0 value."""
 
     return 1-(0 in [x in checklist for x in candidates])
 
 #----------------------------------------------------------------------------
 def sort_compare(lst1,lst2,inplace = 1):
     """Sort and compare two lists.
 
     By default it does it in place, thus modifying the lists. Use inplace = 0
     to avoid that (at the cost of temporary copy creation)."""
     if not inplace:
         lst1 = lst1[:]
         lst2 = lst2[:]
     lst1.sort(); lst2.sort()
     return lst1 == lst2
 
 #----------------------------------------------------------------------------
 def mkdict(**kwargs):
     """Return a dict from a keyword list.
 
     It's just syntactic sugar for making ditcionary creation more convenient:
     # the standard way
     >>>data = { 'red' : 1, 'green' : 2, 'blue' : 3 }
     # a cleaner way
     >>>data = dict(red=1, green=2, blue=3)
 
     If you need more than this, look at the Struct() class."""
 
     return kwargs
 
 #----------------------------------------------------------------------------
 def list2dict(lst):
     """Takes a list of (key,value) pairs and turns it into a dict."""
 
     dic = {}
     for k,v in lst: dic[k] = v
     return dic
 
 #----------------------------------------------------------------------------
 def list2dict2(lst,default=''):
     """Takes a list and turns it into a dict.
     Much slower than list2dict, but more versatile. This version can take
     lists with sublists of arbitrary length (including sclars)."""
 
     dic = {}
     for elem in lst:
         if type(elem) in (types.ListType,types.TupleType):
             size = len(elem)
             if  size == 0:
                 pass
             elif size == 1:
                 dic[elem] = default
             else:
                 k,v = elem[0], elem[1:]
                 if len(v) == 1: v = v[0]
                 dic[k] = v
         else:
             dic[elem] = default
     return dic
 
 #----------------------------------------------------------------------------
 def flatten(seq):
     """Flatten a list of lists (NOT recursive, only works for 2d lists)."""
 
     return [x for subseq in seq for x in subseq]
 
 #----------------------------------------------------------------------------
 def get_slice(seq,start=0,stop=None,step=1):
     """Get a slice of a sequence with variable step. Specify start,stop,step."""
     if stop == None:
         stop = len(seq)
     item = lambda i: seq[i]
     return map(item,xrange(start,stop,step))
 
 #----------------------------------------------------------------------------
 def chop(seq,size):
     """Chop a sequence into chunks of the given size."""
     chunk = lambda i: seq[i:i+size]
     return map(chunk,xrange(0,len(seq),size))
 
 #----------------------------------------------------------------------------
 # with is a keyword as of python 2.5, so this function is renamed to withobj
 # from its old 'with' name.
 def with_obj(object, **args):
     """Set multiple attributes for an object, similar to Pascal's with.
 
     Example:
     with_obj(jim,
              born = 1960,
              haircolour = 'Brown',
              eyecolour = 'Green')
 
     Credit: Greg Ewing, in
     http://mail.python.org/pipermail/python-list/2001-May/040703.html.
 
     NOTE: up until IPython 0.7.2, this was called simply 'with', but 'with'
     has become a keyword for Python 2.5, so we had to rename it."""
 
     object.__dict__.update(args)
 
 #----------------------------------------------------------------------------
 def setattr_list(obj,alist,nspace = None):
     """Set a list of attributes for an object taken from a namespace.
 
     setattr_list(obj,alist,nspace) -> sets in obj all the attributes listed in
     alist with their values taken from nspace, which must be a dict (something
     like locals() will often do) If nspace isn't given, locals() of the
     *caller* is used, so in most cases you can omit it.
 
     Note that alist can be given as a string, which will be automatically
     split into a list on whitespace. If given as a list, it must be a list of
     *strings* (the variable names themselves), not of variables."""
 
     # this grabs the local variables from the *previous* call frame -- that is
     # the locals from the function that called setattr_list().
     # - snipped from weave.inline()
     if nspace is None:
         call_frame = sys._getframe().f_back
         nspace = call_frame.f_locals
 
     if type(alist) in StringTypes:
         alist = alist.split()
     for attr in alist:
         val = eval(attr,nspace)
         setattr(obj,attr,val)
 
 #----------------------------------------------------------------------------
 def getattr_list(obj,alist,*args):
     """getattr_list(obj,alist[, default]) -> attribute list.
 
     Get a list of named attributes for an object. When a default argument is
     given, it is returned when the attribute doesn't exist; without it, an
     exception is raised in that case.
 
     Note that alist can be given as a string, which will be automatically
     split into a list on whitespace. If given as a list, it must be a list of
     *strings* (the variable names themselves), not of variables."""
 
     if type(alist) in StringTypes:
         alist = alist.split()
     if args:
         if len(args)==1:
             default = args[0]
             return map(lambda attr: getattr(obj,attr,default),alist)
         else:
             raise ValueError,'getattr_list() takes only one optional argument'
     else:
         return map(lambda attr: getattr(obj,attr),alist)
     
 #----------------------------------------------------------------------------
 def map_method(method,object_list,*argseq,**kw):
     """map_method(method,object_list,*args,**kw) -> list
 
     Return a list of the results of applying the methods to the items of the
     argument sequence(s).  If more than one sequence is given, the method is
     called with an argument list consisting of the corresponding item of each
     sequence. All sequences must be of the same length.
 
     Keyword arguments are passed verbatim to all objects called.
 
     This is Python code, so it's not nearly as fast as the builtin map()."""
 
     out_list = []
     idx = 0
     for object in object_list:
         try:
             handler = getattr(object, method)
         except AttributeError:
             out_list.append(None)
         else:
             if argseq:
                 args = map(lambda lst:lst[idx],argseq)
                 #print 'ob',object,'hand',handler,'ar',args # dbg
                 out_list.append(handler(args,**kw))
             else:
                 out_list.append(handler(**kw))
         idx += 1
     return out_list
 
 #----------------------------------------------------------------------------
 def get_class_members(cls):
     ret = dir(cls)
     if hasattr(cls,'__bases__'):
         for base in cls.__bases__:
             ret.extend(get_class_members(base))
     return ret
 
 #----------------------------------------------------------------------------
 def dir2(obj):
     """dir2(obj) -> list of strings
 
     Extended version of the Python builtin dir(), which does a few extra
     checks, and supports common objects with unusual internals that confuse
     dir(), such as Traits and PyCrust.
 
     This version is guaranteed to return only a list of true strings, whereas
     dir() returns anything that objects inject into themselves, even if they
     are later not really valid for attribute access (many extension libraries
     have such bugs).
     """
     
     # Start building the attribute list via dir(), and then complete it
     # with a few extra special-purpose calls.
     words = dir(obj)
 
     if hasattr(obj,'__class__'):
         words.append('__class__')
         words.extend(get_class_members(obj.__class__))
     #if '__base__' in words: 1/0
 
     # Some libraries (such as traits) may introduce duplicates, we want to
     # track and clean this up if it happens
     may_have_dupes = False
 
     # this is the 'dir' function for objects with Enthought's traits
     if hasattr(obj, 'trait_names'):
         try:
             words.extend(obj.trait_names())
             may_have_dupes = True
         except TypeError:
             # This will happen if `obj` is a class and not an instance.
             pass
 
     # Support for PyCrust-style _getAttributeNames magic method.
     if hasattr(obj, '_getAttributeNames'):
         try:
             words.extend(obj._getAttributeNames())
             may_have_dupes = True
         except TypeError:
             # `obj` is a class and not an instance.  Ignore
             # this error.
             pass
 
     if may_have_dupes:
         # eliminate possible duplicates, as some traits may also
         # appear as normal attributes in the dir() call.
         words = list(set(words))
         words.sort()
 
     # filter out non-string attributes which may be stuffed by dir() calls
     # and poor coding in third-party modules
     return [w for w in words if isinstance(w, basestring)]
 
 #----------------------------------------------------------------------------
 def import_fail_info(mod_name,fns=None):
     """Inform load failure for a module."""
 
     if fns == None:
         warn("Loading of %s failed.\n" % (mod_name,))
     else:
         warn("Loading of %s from %s failed.\n" % (fns,mod_name))
 
 #----------------------------------------------------------------------------
 # Proposed popitem() extension, written as a method
 
 
 class NotGiven: pass
 
 def popkey(dct,key,default=NotGiven):
     """Return dct[key] and delete dct[key].
 
     If default is given, return it if dct[key] doesn't exist, otherwise raise
     KeyError.  """
 
     try:
         val = dct[key]
     except KeyError:
         if default is NotGiven:
             raise
         else:
             return default
     else:
         del dct[key]
         return val
 
 def wrap_deprecated(func, suggest = '<nothing>'):
     def newFunc(*args, **kwargs):
         warnings.warn("Call to deprecated function %s, use %s instead" % 
                       ( func.__name__, suggest),
                       category=DeprecationWarning,
                       stacklevel = 2)
         return func(*args, **kwargs)
     return newFunc
     
 #*************************** end of file <genutils.py> **********************
 

IPython/iplib.py

@@ -1,2471 +1,2475 b''
 # -*- coding: utf-8 -*-
 """
 IPython -- An enhanced Interactive Python
 
 Requires Python 2.3 or newer.
 
 This file contains all the classes and helper functions specific to IPython.
 
-$Id: iplib.py 2571 2007-08-01 14:48:03Z vivainio $
+$Id: iplib.py 2577 2007-08-02 23:50:02Z fperez $
 """
 
 #*****************************************************************************
 #       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
 
 from IPython import Release
 __author__  = '%s <%s>\n%s <%s>' % \
               ( Release.authors['Janko'] + Release.authors['Fernando'] )
 __license__ = Release.license
 __version__ = Release.version
 
 # 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
 import pickleshare
 from sets import Set
 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.FakeModule import FakeModule
 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
 
 
 #****************************************************************************
 # 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')
 
         # some minimal strict typechecks.  For some core data structures, I
         # want actual basic python types, not just anything that looks like
         # one.  This is especially true for namespaces.
         for ns in (user_ns,user_global_ns):
             if ns is not None and type(ns) != types.DictType:
                 raise TypeError,'namespace must be a dictionary'
 
         # Job manager (for jobs run as background threads)
         self.jobs = BackgroundJobManager()
 
         # Store the actual shell's name
         self.name = name
 
         # 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.
 
         # 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 = IPython.ipapi.make_user_ns(user_ns)
         user_global_ns = IPython.ipapi.make_user_global_ns(user_global_ns)
             
         # Assign namespaces
         # This is the namespace where all normal user variables live
         self.user_ns = user_ns
         # Embedded instances require a separate namespace for globals.
         # Normally this one is unused by non-embedded instances.
         self.user_global_ns = user_global_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 = {}
 
         # 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__
                          }
 
         # The user namespace MUST have a pointer to the shell itself.
         self.user_ns[name] = self
 
         # 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.
         # Fill its zero entry, user counter starts at 1
         self.input_hist = InputList(['\n'])
         # 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(['\n'])
 
         # 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
         self.stdin_encoding = sys.stdin.encoding or '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
                 
         # make global variables for user access to these
         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
         # 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 = [os.getcwd().replace(self.home_dir,'~')]
 
         # 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: \
                       shell(self.var_expand(cmd,depth=2),
                             header=self.rc.system_header,
                             verbose=self.rc.system_verbose)
 
         # 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 = ('dir dir /on', '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]
         # Call the actual (public) initializer
         self.init_auto_alias()
 
         # Produce a public API instance
         self.api = IPython.ipapi.IPApi(self)
 
         # 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.
         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.replace('#','\#'),
                           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
         
         # 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()
         
         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
         if batchrun:
             self.exit_now = True            
 
     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 except _ip; 'jobs' should be installed 
         # by an extension and the rest are under _ip, ipalias is redundant
         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 [1]: x = 'hello'
 
         In [2]: __IP.complete('x.l')
         Out[2]: ['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()
         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.alias_table[alias] = (0,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.
 
         Can be called when running for the first time or to upgrade the user's
         .ipython/ directory with the mode parameter. Valid modes are 'install'
         and 'upgrade'."""
 
         def wait():
             try:
                 raw_input("Please press <RETURN> to start IPython.")
             except EOFError:
                 print >> Term.cout
             print '*'*70
 
         cwd = os.getcwd()  # remember where we started
         glb = glob.glob
         print '*'*70
         if mode == 'install':
             print \
 """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:
             print 'I am going to upgrade your configuration in:'
 
         print 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]
         except IOError:
             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 proceed with builtin defaults.
 """
             warn(warning)
             wait()
             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:
                 print """
 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:',`mode`
 
         # Fix line-endings to those native to each platform in the config
         # directory.
         try:
             os.chdir(ipythondir)
         except:
             print """
 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':
             print """
 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:
             print """
 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)
         # end user_setup()
 
     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
 
         self.hooks.shutdown_hook()
         
     def savehist(self):
         """Save input history to a file (via readline library)."""
         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:
             self.readline.clear_history()
             self.readline.read_history_file(self.shell.histfile)
 
     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)
             inputrc_name = os.environ.get('INPUTRC')
             if inputrc_name is None:
                 home_dir = get_home_dir()
                 if home_dir is not None:
                     inputrc_name = os.path.join(home_dir,'.inputrc')
             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
             for rlcommand in self.rc.readline_parse_and_bind:
                 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 _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
         self.hooks.fix_error_editor(e.filename,
             int0(e.lineno),int0(e.offset),e.msg)
         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.
         
         
         if exc_tuple is None:
             etype, value, tb = sys.exc_info()
         else:
             etype, value, tb = exc_tuple
 
         if etype is SyntaxError:
             self.showsyntaxerror(filename)
         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()
         
 
     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
 
         self.interact(banner)
 
     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))
         self.exit_now = True
 
     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)
 
         # 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(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 readline.have_readline:
             self.readline_startup_hook(self.pre_readline)
         # exit_now is set by a call to %Exit or %Quit
         
         while not self.exit_now:
             if more:
                 prompt = self.hooks.generate_prompt(True)
                 if self.autoindent:
                     self.rl_do_indent = True
                     
             else:
                 prompt = self.hooks.generate_prompt(False)
             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:
                 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 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.
         """
         nargs,cmd = self.alias_table[alias]
         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
         # 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
         if source[:1] in [' ', '\t']:
             source = 'if 1:\n%s' % source
 
         try:
             code = self.compile(source,filename,symbol)
         except (OverflowError, SyntaxError, ValueError):
             # 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:
                 # Embedded instances require separate global/local namespaces
                 # so they can see both the surrounding (local) namespace and
                 # the module-level globals when called inside another function.
                 if self.embedded:
                     exec code_obj in self.user_global_ns, self.user_ns
                 # Normal (non-embedded) instances should only have a single
                 # namespace for user code execution, otherwise functions won't
                 # see interactive top-level globals.
                 else:
                     exec code_obj in 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.exit_now = True
             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()
                         newhist = self.input_hist_raw[-1].rstrip()
                         self.readline.remove_history_item(histlen-1)
                         self.readline.replace_history_item(histlen-2,newhist)
                     except AttributeError:
                         pass # re{move,place}_history_item are new in 2.4.                
             else:
                 self.input_hist_raw.append('%s\n' % line)                
         
             if line.lstrip() == line:
                 self.shadowhist.add(line.strip())
             
         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
 
         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):
             line_out = "_sh." + line_info.iFun + '(r"""' + line_info.theRest + '""")'
         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."""
 
         #print 'pre <%s> iFun <%s> rest <%s>' % (pre,iFun,theRest)  # dbg
         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']
         
         # 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 exit(self):
         """Handle interactive exit.
 
         This method sets the exit_now attribute."""
 
         if self.rc.confirm_exit:
             if self.ask_yes_no('Do you really want to exit ([y]/n)?','y'):
                 self.exit_now = True
         else:
             self.exit_now = True
 
     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."""
 
         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:
                 if not kw['exit_ignore']:
                     self.showtraceback()
                     warn('Failure executing file: <%s>' % fname)
             except:
                 self.showtraceback()
                 warn('Failure executing file: <%s>' % fname)
 
         syspath_cleanup()
 
 #************************* end of file <iplib.py> *****************************

doc/examples/example-embed.py

@@ -1,129 +1,131 b''
 #!/usr/bin/env python
 
 """An example of how to embed an IPython shell into a running program.
 
 Please see the documentation in the IPython.Shell module for more details.
 
 The accompanying file example-embed-short.py has quick code fragments for
 embedding which you can cut and paste in your code once you understand how
 things work.
 
 The code in this file is deliberately extra-verbose, meant for learning."""
 
 # The basics to get you going:
 
 # IPython sets the __IPYTHON__ variable so you can know if you have nested
 # copies running.
 
 # Try running this code both at the command line and from inside IPython (with
 # %run example-embed.py)
 try:
     __IPYTHON__
 except NameError:
     nested = 0
     args = ['']
 else:
     print "Running nested copies of IPython."
     print "The prompts for the nested copy have been modified"
     nested = 1
     # what the embedded instance will see as sys.argv:
     args = ['-pi1','In <\\#>: ','-pi2','   .\\D.: ',
             '-po','Out<\\#>: ','-nosep']
 
 # First import the embeddable shell class
 from IPython.Shell import IPShellEmbed
 
 # Now create an instance of the embeddable shell. The first argument is a
 # string with options exactly as you would type them if you were starting
 # IPython at the system command line. Any parameters you want to define for
 # configuration can thus be specified here.
 ipshell = IPShellEmbed(args,
                        banner = 'Dropping into IPython',
                        exit_msg = 'Leaving Interpreter, back to program.')
 
 # Make a second instance, you can have as many as you want.
 if nested:
     args[1] = 'In2<\\#>'
 else:
     args = ['-pi1','In2<\\#>: ','-pi2','   .\\D.: ',
             '-po','Out<\\#>: ','-nosep']
 ipshell2 = IPShellEmbed(args,banner = 'Second IPython instance.')
 
 print '\nHello. This is printed from the main controller program.\n'
 
 # You can then call ipshell() anywhere you need it (with an optional
 # message):
 ipshell('***Called from top level. '
-        'Hit Ctrl-D to exit interpreter and continue program.')
+        'Hit Ctrl-D to exit interpreter and continue program.\n'
+        'Note that if you use %kill_embedded, you can fully deactivate\n'
+        'This embedded instance so it will never turn on again')
 
 print '\nBack in caller program, moving along...\n'
 
 #---------------------------------------------------------------------------
 # More details:
 
 # IPShellEmbed instances don't print the standard system banner and
 # messages. The IPython banner (which actually may contain initialization
 # messages) is available as <instance>.IP.BANNER in case you want it.
 
 # IPShellEmbed instances print the following information everytime they
 # start:
 
 # - A global startup banner.
 
 # - A call-specific header string, which you can use to indicate where in the
 # execution flow the shell is starting.
 
 # They also print an exit message every time they exit.
 
 # Both the startup banner and the exit message default to None, and can be set
 # either at the instance constructor or at any other time with the
 # set_banner() and set_exit_msg() methods.
 
 # The shell instance can be also put in 'dummy' mode globally or on a per-call
 # basis. This gives you fine control for debugging without having to change
 # code all over the place.
 
 # The code below illustrates all this.
 
 
 # This is how the global banner and exit_msg can be reset at any point
 ipshell.set_banner('Entering interpreter - New Banner')
 ipshell.set_exit_msg('Leaving interpreter - New exit_msg')
 
 def foo(m):
     s = 'spam'
     ipshell('***In foo(). Try @whos, or print s or m:')
     print 'foo says m = ',m
 
 def bar(n):
     s = 'eggs'
     ipshell('***In bar(). Try @whos, or print s or n:')
     print 'bar says n = ',n
     
 # Some calls to the above functions which will trigger IPython:
 print 'Main program calling foo("eggs")\n'
 foo('eggs')
 
 # The shell can be put in 'dummy' mode where calls to it silently return. This
 # allows you, for example, to globally turn off debugging for a program with a
 # single call.
 ipshell.set_dummy_mode(1)
 print '\nTrying to call IPython which is now "dummy":'
 ipshell()
 print 'Nothing happened...'
 # The global 'dummy' mode can still be overridden for a single call
 print '\nOverriding dummy mode manually:'
 ipshell(dummy=0)
 
 # Reactivate the IPython shell
 ipshell.set_dummy_mode(0)
 
 print 'You can even have multiple embedded instances:'
 ipshell2()
 
 print '\nMain program calling bar("spam")\n'
 bar('spam')
 
 print 'Main program finished. Bye!'
 
 #********************** End of file <example-embed.py> ***********************