Semi-final Application and minor work on traitlets.

IPython/config/loader.py

@@ -1,198 +1,200 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """A factory for creating configuration objects.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import os
 import sys
 
 from IPython.external import argparse
 from IPython.utils.ipstruct import Struct
+from IPython.utils.genutils import filefind
 
 #-----------------------------------------------------------------------------
 # Code
 #-----------------------------------------------------------------------------
 
 
 class ConfigLoaderError(Exception):
     pass
 
 
 class ConfigLoader(object):
     """A object for loading configurations from just about anywhere.
     
     The resulting configuration is packaged as a :class:`Struct`.
     
     Notes
     -----
     A :class:`ConfigLoader` does one thing: load a config from a source 
     (file, command line arguments) and returns the data as a :class:`Struct`.
     There are lots of things that :class:`ConfigLoader` does not do.  It does
     not implement complex logic for finding config files.  It does not handle
     default values or merge multiple configs.  These things need to be 
     handled elsewhere.
     """
 
     def __init__(self):
         """A base class for config loaders.
         
         Examples
         --------
         
         >>> cl = ConfigLoader()
         >>> config = cl.load_config()
         >>> config
         {}
         """
         self.clear()
 
     def clear(self):
         self.config = Struct()
 
     def load_config(self):
         """Load a config from somewhere, return a Struct.
         
         Usually, this will cause self.config to be set and then returned.
         """
         return self.config
 
 
 class FileConfigLoader(ConfigLoader):
     """A base class for file based configurations.
 
     As we add more file based config loaders, the common logic should go
     here.
     """
     pass
 
 
 class PyFileConfigLoader(FileConfigLoader):
     """A config loader for pure python files.
     
     This calls execfile on a plain python file and looks for attributes
     that are all caps.  These attribute are added to the config Struct.
     """
 
-    def __init__(self, filename, path='.'):
+    def __init__(self, filename, path=None):
         """Build a config loader for a filename and path.
 
         Parameters
         ----------
         filename : str
             The file name of the config file.
         path : str, list, tuple
             The path to search for the config file on, or a sequence of
             paths to try in order.
         """
         super(PyFileConfigLoader, self).__init__()
         self.filename = filename
         self.path = path
         self.full_filename = ''
         self.data = None
 
     def load_config(self):
         """Load the config from a file and return it as a Struct."""
         self._find_file()
         self._read_file_as_dict()
         self._convert_to_struct()
         return self.config
 
     def _find_file(self):
         """Try to find the file by searching the paths."""
-        if os.path.isfile(os.path.expanduser(self.filename)):
-            self.full_filename = os.path.expanduser(self.filename)
-            return
-        if self.path == '.':
-            self.path = [os.getcwd()]
-        if not isinstance(path, (list, tuple)):
-            raise TypeError("path must be a list or tuple, got: %r" % self.path)
-        for p in self.path:
-            if p == '.': p = os.getcwd()
-            full_filename = os.path.expanduser(os.path.join(p, self.filename))
-            if os.path.isfile(full_filename):
-                self.full_filename = full_filename
-                return
-        raise IOError("Config file does not exist in any "
-                      "of the search paths: %r, %r" % \
-                      (self.filename, self.path))
+        self.full_filename = filefind(self.filename, self.path)
 
     def _read_file_as_dict(self):
         self.data = {}
         execfile(self.full_filename, self.data)
 
     def _convert_to_struct(self):
         if self.data is None:
             ConfigLoaderError('self.data does not exist')
         for k, v in self.data.iteritems():
             if k == k.upper():
                 self.config[k] = v
 
 
 class CommandLineConfigLoader(ConfigLoader):
     """A config loader for command line arguments.
 
     As we add more command line based loaders, the common logic should go
     here.
     """
 
 
 class NoDefault(object): pass
 NoDefault = NoDefault()
 
 class ArgParseConfigLoader(CommandLineConfigLoader):
     
     # arguments = [(('-f','--file'),dict(type=str,dest='file'))]
     arguments = ()
 
     def __init__(self, *args, **kw):
         """Create a config loader for use with argparse.
 
         The args and kwargs arguments here are passed onto the constructor
         of :class:`argparse.ArgumentParser`.
         """
         super(CommandLineConfigLoader, self).__init__()
         self.args = args
         self.kw = kw
 
     def load_config(self, args=None):
         """Parse command line arguments and return as a Struct."""
         self._create_parser()
         self._parse_args(args)
         self._convert_to_struct()
         return self.config
 
     def _create_parser(self):
         self.parser = argparse.ArgumentParser(*self.args, **self.kw)
         self._add_arguments()
+        self._add_other_arguments()
+
+    def _add_other_arguments():
+        pass
 
     def _add_arguments(self):
         for argument in self.arguments:
             if not argument[1].has_key('default'):
                 argument[1]['default'] = NoDefault
             self.parser.add_argument(*argument[0],**argument[1])
 
     def _parse_args(self, args=None):
         """self.parser->self.parsed_data"""
         if args is None:
             self.parsed_data = self.parser.parse_args()
         else:
             self.parsed_data = self.parser.parse_args(args)
 
     def _convert_to_struct(self):
         """self.parsed_data->self.config"""
         self.config = Struct()
         for k, v in vars(self.parsed_data).items():
             if v is not NoDefault:
                 setattr(self.config, k, v)
 
+class IPythonArgParseConfigLoader(ArgParseConfigLoader):
+
+    def _add_other_arguments(self):
+        self.parser.add_argument('--ipythondir',dest='IPYTHONDIR',type=str,
+            help='set to override default location of IPYTHONDIR',
+            default=NoDefault)
+        self.parser.add_argument('-p','--p',dest='PROFILE_NAME',type=str,
+            help='the string name of the ipython profile to be used',
+            default=None)
+        self.parser.add_argument('--debug',dest="DEBUG",action='store_true',
+            help='debug the application startup process',
+            default=NoDefault)

IPython/core/application.py

@@ -1,161 +1,231 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 An application for IPython
 
 Authors:
 
 * Brian Granger
 * Fernando Perez
 
 Notes
 -----
-
-The following directories are relevant in the startup of an app:
-
-* The ipythondir.  This has a default, but can be set by IPYTHONDIR or at
-  the command line.
-* The current working directory.
-* Another runtime directory.  With some applications (engine, controller) we
-  need the ability to have different cluster configs.  Each of these needs
-  to have its own config, security dir and log dir.  We could simply treat
-  these as regular ipython dirs.  
-
-There are number of ways in which these directories are used:
-
-* For config files.
-* For other assets and resources needed to run.  These include 
-  plugins, magics, furls files.
-* For writing various things created at runtime like logs, furl files, etc.
-
-Questions:
-
-
-* Can we limit ourselves to 1 config file or do we want to have a sequence
-  of them like IPYTHONDIR->RUNTIMEDIR->CWD? [1]
-* Do we need a debug mode that has custom exception handling and can drop
-  into pdb upno startup? N
-* Do we need to use an OutputTrap to capture output and then present it
-  to a user if startup fails? N
-* Do we want the location of the config file(s) to be independent of the
-  ipython/runtime dir or coupled to it.  In other words, can the user select
-  a config file that is outside their runtime/ipython dir.  One model is 
-  that we could have a very strict model of IPYTHONDIR=runtimed dir=
-  dir used for all config.
-* Do we install default config files or not? N
-
-* attempt needs to either clash or to die
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
+import os
 import sys
+import traceback
+
 from copy import deepcopy
 from IPython.utils.ipstruct import Struct
+from IPython.utils.genutils import get_ipython_dir, filefind
+from IPython.config.loader import (
+    IPythonArgParseConfigLoader,
+    PyFileConfigLoader
+)
 
 #-----------------------------------------------------------------------------
 # Classes and functions
 #-----------------------------------------------------------------------------
 
 
 class ApplicationError(Exception):
     pass
 
 
 class Application(object):
+    """Load a config, construct an app and run it.
+    """
 
-    runtime_dirs = []
-    default_config = Struct()
-    runtime_dir = ''
-    config_file = ''
-    name = ''
+    config_file_name = 'ipython_config.py'
+    name = 'ipython'
+    debug = False
 
     def __init__(self):
         pass
 
     def start(self):
         """Start the application."""
-        self.attempt(self.create_command_line_config)
-        self.attempt(self.find_runtime_dirs)
-        self.attempt(self.create_runtime_dirs)
-        self.attempt(self.find_config_files)
-        self.attempt(self.create_file_configs)
+        self.attempt(self.create_default_config)
+        self.attempt(self.pre_load_command_line_config)
+        self.attempt(self.load_command_line_config, action='exit')
+        self.attempt(self.post_load_command_line_config)
+        self.attempt(self.find_ipythondir)
+        self.attempt(self.find_config_file_name)
+        self.attempt(self.find_config_file_paths)
+        self.attempt(self.pre_load_file_config)
+        self.attempt(self.load_file_config)
+        self.attempt(self.post_load_file_config)
         self.attempt(self.merge_configs)
+        self.attempt(self.pre_construct)
         self.attempt(self.construct)
-        self.attempt(self.start_logging)
+        self.attempt(self.post_construct)
         self.attempt(self.start_app)
 
     #-------------------------------------------------------------------------
     # Various stages of Application creation
     #-------------------------------------------------------------------------
 
+    def create_default_config(self):
+        """Create defaults that can't be set elsewhere."""
+        self.default_config = Struct()
+        self.default_config.IPYTHONDIR = get_ipython_dir()
+
     def create_command_line_config(self):
-        """Read the command line args and return its config object."""
-        self.command_line_config = Struct()
+        """Create and return a command line config loader."""
+        return IPythonArgParseConfigLoader(description=self.name)
+
+    def pre_load_command_line_config(self):
+        """Do actions just before loading the command line config."""
+        pass
 
-    def find_runtime_dirs(self):
-        """Find the runtime directory for this application.
+    def load_command_line_config(self):
+        """Load the command line config.
 
-        This should set self.runtime_dir.
+        This method also sets ``self.debug``.
         """
-        pass
 
-    def create_runtime_dirs(self):
-        """Create the runtime dirs if they don't exist."""
+        loader = self.create_command_line_config()
+        self.command_line_config = loader.load_config()
+        try:
+            self.debug = self.command_line_config.DEBUG
+        except AttributeError:
+            pass # use class default
+        self.log("Default config loaded:", self.default_config)
+        self.log("Command line config loaded:", self.command_line_config)
+
+    def post_load_command_line_config(self):
+        """Do actions just after loading the command line config."""
         pass
 
-    def find_config_files(self):
-        """Find the config file for this application."""
+    def find_ipythondir(self):
+        """Set the IPython directory.
+
+        This sets ``self.ipythondir``, but the actual value that is passed
+        to the application is kept in either ``self.default_config`` or
+        ``self.command_line_config``.  This also added ``self.ipythondir`` to
+        ``sys.path`` so config files there can be references by other config
+        files.
+        """
+
+        try:
+            self.ipythondir = self.command_line_config.IPYTHONDIR
+        except AttributeError:
+            self.ipythondir = self.default_config.IPYTHONDIR
+        sys.path.append(os.path.abspath(self.ipythondir))
+        self.log("IPYTHONDIR set to: %s" % self.ipythondir)
+
+    def find_config_file_name(self):
+        """Find the config file name for this application.
+
+        If a profile has been set at the command line, this will resolve
+        it.  The search paths for the config file are set in
+        :meth:`find_config_file_paths` and then passed to the config file
+        loader where they are resolved to an absolute path.
+        """
+
+        if self.command_line_config.PROFILE_NAME is not None:
+            self.profile_name = self.command_line_config.PROFILE_NAME
+            name_parts = self.config_file_name.split('.')
+            name_parts.insert(1, '_' + self.profile_name + '.')
+            self.config_file_name = ''.join(name_parts)
+
+    def find_config_file_paths(self):
+        """Set the search paths for resolving the config file."""
+        self.config_file_paths = (os.getcwd(), self.ipythondir)
+
+    def pre_load_file_config(self):
+        """Do actions before the config file is loaded."""
         pass
 
-    def create_file_configs(self):
-        self.file_configs = [Struct()]
+    def load_file_config(self):
+        """Load the config file.
+        
+        This tries to load the config file from disk.  If successful, the
+        ``CONFIG_FILE`` config variable is set to the resolved config file
+        location.  If not successful, an empty config is used.
+        """
+        loader = PyFileConfigLoader(self.config_file_name, 
+                                    self.config_file_paths)
+        try:
+            self.file_config = loader.load_config()
+            self.file_config.CONFIG_FILE = loader.full_filename
+        except IOError:
+            self.log("Config file not found, skipping: %s" % \
+                     self.config_file_name)
+            self.file_config = Struct()
+        else:
+            self.log("Config file loaded: %s" % loader.full_filename)
+
+    def post_load_file_config(self):
+        """Do actions after the config file is loaded."""
+        pass
 
     def merge_configs(self):
+        """Merge the default, command line and file config objects."""
         config = Struct()
-        all_configs = self.file_configs + self.command_line_config
-        for c in all_configs:
-            config.update(c)
+        config.update(self.default_config)
+        config.update(self.command_line_config)
+        config.update(self.file_config)
         self.master_config = config
+        self.log("Master config created:", self.master_config)
 
-    def construct(self, config):
-        """Construct the main components that make up this app."""
+    def pre_construct(self):
+        """Do actions after the config has been built, but before construct."""
         pass
 
-    def start_logging(self):
-        """Start logging, if needed, at the last possible moment."""
+    def construct(self):
+        """Construct the main components that make up this app."""
+        self.log("Constructing components for application...")
+
+    def post_construct(self):
+        """Do actions after construct, but before starting the app."""
         pass
 
     def start_app(self):
         """Actually start the app."""
-        pass
+        self.log("Starting application...")
 
     #-------------------------------------------------------------------------
     # Utility methods
     #-------------------------------------------------------------------------
 
     def abort(self):
         """Abort the starting of the application."""
         print "Aborting application: ", self.name
         sys.exit(1)
 
-    def attempt(self, func):
+    def exit(self):
+        print "Exiting application: ", self.name
+        sys.exit(1)
+
+    def attempt(self, func, action='abort'):
         try:
             func()
         except:
-            self.handle_error()
-            self.abort()
-
-    def handle_error(self):
-        print "I am dying!"
-     
-        
  No newline at end of file
+            if action == 'abort':
+                self.print_traceback()
+                self.abort()
+            elif action == 'exit':
+                self.exit()
+
+    def print_traceback(self):
+        print "Error in appliction startup: ", self.name
+        print
+        traceback.print_exc()
+
+    def log(self, *args):
+        if self.debug:
+            for arg in args:
+                print "[%s] %s" % (self.name, arg)        
  No newline at end of file

IPython/core/component.py

@@ -1,225 +1,225 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 A lightweight component system for IPython.
 
 Authors:
 
 * Brian Granger
 * Fernando Perez
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 from copy import deepcopy
 from weakref import WeakValueDictionary
 
 from IPython.utils.ipstruct import Struct
 from IPython.utils.traitlets import (
     HasTraitlets, TraitletError, MetaHasTraitlets, Instance, This
 )
 
 
 #-----------------------------------------------------------------------------
 # Helper classes for Components
 #-----------------------------------------------------------------------------
 
 
 class ComponentError(Exception):
     pass
 
 class MetaComponentTracker(type):
     """A metaclass that tracks instances of Components and its subclasses."""
 
     def __init__(cls, name, bases, d):
         super(MetaComponentTracker, cls).__init__(name, bases, d)
         cls.__instance_refs = WeakValueDictionary()
         cls.__numcreated = 0
 
     def __call__(cls, *args, **kw):
         """Called when *class* is called (instantiated)!!!
         
         When a Component or subclass is instantiated, this is called and
         the instance is saved in a WeakValueDictionary for tracking.
         """
 
         instance = super(MetaComponentTracker, cls).__call__(*args, **kw)
         for c in cls.__mro__:
             if issubclass(cls, c) and issubclass(c, Component):
                 c.__numcreated += 1
                 c.__instance_refs[c.__numcreated] = instance
         return instance
 
     def get_instances(cls, name=None, klass=None, root=None):
         """Get all instances of cls and its subclasses.
 
         Parameters
         ----------
         name : str
             Limit to components with this name.
         klass : class
             Limit to components having isinstance(component, klass)
         root : Component or subclass
             Limit to components having this root.
         """
         instances = cls.__instance_refs.values()
         if name is not None:
             instances = [i for i in instances if i.name == name]
         if klass is not None:
             instances = [i for i in instances if isinstance(i, klass)]
         if root is not None:
             instances = [i for i in instances if i.root == root]
         return instances
 
     def get_instances_by_condition(cls, call, name=None, klass=None, root=None):
         """Get all instances of cls, i such that call(i)==True.
 
         This also takes the ``name``, ``klass`` and ``root`` arguments of
         :meth:`get_instance`
         """
         return [i for i in cls.get_instances(name,klass,root) if call(i)]
 
 
 class ComponentNameGenerator(object):
     """A Singleton to generate unique component names."""
 
     def __init__(self, prefix):
         self.prefix = prefix
         self.i = 0
 
     def __call__(self):
         count = self.i
         self.i += 1
         return "%s%s" % (self.prefix, count)
 
 
 ComponentNameGenerator = ComponentNameGenerator('ipython.component')
 
 
 class MetaComponent(MetaHasTraitlets, MetaComponentTracker):
     pass
 
 
 #-----------------------------------------------------------------------------
 # Component implementation
 #-----------------------------------------------------------------------------
 
 
 class Component(HasTraitlets):
 
     __metaclass__ = MetaComponent
 
     # Traitlets are fun!
     config = Instance(Struct,(),{})
     parent = This()
     root = This()
 
     def __init__(self, parent, name=None, config=None):
         """Create a component given a parent and possibly and name and config.
 
         Parameters
         ----------
         parent : Component subclass
             The parent in the component graph.  The parent is used
             to get the root of the component graph.
         name : str
             The unique name of the component.  If empty, then a unique
             one will be autogenerated.
         config : Struct
             If this is empty, self.config = parent.config, otherwise
             self.config = config and root.config is ignored.  This argument
             should only be used to *override* the automatic inheritance of 
             parent.config.  If a caller wants to modify parent.config 
             (not override), the caller should make a copy and change 
             attributes and then pass the copy to this argument.
         
         Notes
         -----
         Subclasses of Component must call the :meth:`__init__` method of
         :class:`Component` *before* doing anything else and using 
         :func:`super`::
         
             class MyComponent(Component):
                 def __init__(self, parent, name=None, config=None):
                     super(MyComponent, self).__init__(parent, name, config)
                     # Then any other code you need to finish initialization.
 
         This ensures that the :attr:`parent`, :attr:`name` and :attr:`config`
         attributes are handled properly.
         """
         super(Component, self).__init__()
         self._children = []
         if name is None:
             self.name = ComponentNameGenerator()
         else:
             self.name = name
         self.root = self # This is the default, it is set when parent is set
         self.parent = parent
         if config is not None:
             self.config = deepcopy(config)
         else:
             if self.parent is not None:
                 self.config = deepcopy(self.parent.config)
 
     #-------------------------------------------------------------------------
     # Static traitlet notifiations
     #-------------------------------------------------------------------------
 
     def _parent_changed(self, name, old, new):
         if old is not None:
             old._remove_child(self)
         if new is not None:
             new._add_child(self)
 
         if new is None:
             self.root = self
         else:
             self.root = new.root
 
     def _root_changed(self, name, old, new):
         if self.parent is None:
             if not (new is self):
                 raise ComponentError("Root not self, but parent is None.")
         else:
             if not self.parent.root is new:
                 raise ComponentError("Error in setting the root attribute: "
                                      "root != parent.root")
 
     def _config_changed(self, name, old, new):
         # Get all traitlets with a config_key metadata entry
-        traitlets = self.traitlets(config_key=lambda v: True)
+        traitlets = self.traitlets('config_key')
         for k, v in traitlets.items():
             try:
                 config_value = new[v.get_metadata('config_key')]
             except KeyError:
                 pass
             else:
                 setattr(self, k, config_value)
 
     @property
     def children(self):
         """A list of all my child components."""
         return self._children
 
     def _remove_child(self, child):
         """A private method for removing children componenets."""
         if child in self._children:
             index = self._children.index(child)
             del self._children[index]
 
     def _add_child(self, child):
         """A private method for adding children componenets."""
         if child not in self._children:
             self._children.append(child)
 
     def __repr__(self):
         return "<Component('%s')>" % self.name

IPython/core/ipmaker.py

@@ -1,790 +1,792 b''
 # -*- coding: utf-8 -*-
 """
 IPython -- An enhanced Interactive Python
 
 Requires Python 2.1 or better.
 
 This file contains the main make_IPython() starter function.
 """
 
 #*****************************************************************************
 #       Copyright (C) 2008-2009 The IPython Development Team
 #       Copyright (C) 2001-2007 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.
 #*****************************************************************************
 
 try:
     credits._Printer__data = """
     Python: %s
 
     IPython: The IPython Development Team.
     See http://ipython.scipy.org for more information.""" \
     % credits._Printer__data
 
     copyright._Printer__data += """
 
     Copyright (c) 2008-2009 The IPython Development Team.
     Copyright (c) 2001-2007 Fernando Perez, Janko Hauser, Nathan Gray.
     All Rights Reserved."""
 except NameError:
     # Can happen if ipython was started with 'python -S', so that site.py is
     # not loaded
     pass
 
 #****************************************************************************
 # Required modules
 
 # From the standard library
 import __main__
 import __builtin__
 import os
 import sys
 from pprint import pprint
 import warnings
 
 # Our own
 from IPython.utils import DPyGetOpt
 from IPython.core import release
 from IPython.utils.ipstruct import Struct
 from IPython.core.outputtrap import OutputTrap
 from IPython.config.configloader import ConfigLoader
 from IPython.core.iplib import InteractiveShell
 from IPython.core.usage import cmd_line_usage, interactive_usage
 from IPython.utils.genutils import *
 
 
 def force_import(modname,force_reload=False):
     if modname in sys.modules and force_reload:
         info("reloading: %s" % modname)
         reload(sys.modules[modname])
     else:
         __import__(modname)
 
 
 def threaded_shell_warning():
     msg = """
 
 The IPython threaded shells and their associated command line
 arguments (pylab/wthread/gthread/qthread/q4thread) have been 
 deprecated.  See the %gui magic for information on the new interface.
 """
     warnings.warn(msg, category=DeprecationWarning, stacklevel=1)
 
 
 #-----------------------------------------------------------------------------
 def make_IPython(argv=None,user_ns=None,user_global_ns=None,debug=1,
                  rc_override=None,shell_class=InteractiveShell,
                  embedded=False,**kw):
     """This is a dump of IPython into a single function.
 
     Later it will have to be broken up in a sensible manner.
 
     Arguments:
 
     - argv: a list similar to sys.argv[1:].  It should NOT contain the desired
     script name, b/c DPyGetOpt strips the first argument only for the real
     sys.argv.
 
     - user_ns: a dict to be used as the user's namespace."""
 
     #----------------------------------------------------------------------
     # Defaults and initialization
     
     # For developer debugging, deactivates crash handler and uses pdb.
-    DEVDEBUG = False
+    DEVDEBUG = True
 
     if argv is None:
         argv = sys.argv
 
     # __IP is the main global that lives throughout and represents the whole
     # application. If the user redefines it, all bets are off as to what
     # happens.
 
     # __IP is the name of he global which the caller will have accessible as
     # __IP.name. We set its name via the first parameter passed to
     # InteractiveShell:
 
     IP = shell_class('__IP',user_ns=user_ns,user_global_ns=user_global_ns,
                      embedded=embedded,**kw)
 
     # Put 'help' in the user namespace
     try:
         from site import _Helper
         IP.user_ns['help'] = _Helper()
     except ImportError:
         warn('help() not available - check site.py')
 
     if DEVDEBUG:
         # For developer debugging only (global flag)
         from IPython.core import ultratb
         sys.excepthook = ultratb.VerboseTB(call_pdb=1)
 
     IP.BANNER_PARTS = ['Python %s\n'
                          'Type "copyright", "credits" or "license" '
                          'for more information.\n'
                          % (sys.version.split('\n')[0],),
                          "IPython %s -- An enhanced Interactive Python."
                          % (release.version,),
 """\
 ?         -> Introduction and overview of IPython's features.
 %quickref -> Quick reference.
 help      -> Python's own help system.
 object?   -> Details about 'object'. ?object also works, ?? prints more.
 """ ]
 
     IP.usage = interactive_usage
 
     # Platform-dependent suffix.
     if os.name == 'posix':
         rc_suffix = ''
     else:
         rc_suffix = '.ini'
 
     # default directory for configuration
     ipythondir_def = get_ipython_dir() 
     
     sys.path.insert(0, '') # add . to sys.path. Fix from Prabhu Ramachandran
 
     # we need the directory where IPython itself is installed
     import IPython
     IPython_dir = os.path.dirname(IPython.__file__)
     del IPython
     
     #-------------------------------------------------------------------------
     # Command line handling
 
     # Valid command line options (uses DPyGetOpt syntax, like Perl's
     # GetOpt::Long)
 
     # Any key not listed here gets deleted even if in the file (like session
     # or profile). That's deliberate, to maintain the rc namespace clean.
 
     # Each set of options appears twice: under _conv only the names are
     # listed, indicating which type they must be converted to when reading the
     # ipythonrc file. And under DPyGetOpt they are listed with the regular
     # DPyGetOpt syntax (=s,=i,:f,etc).
 
     # Make sure there's a space before each end of line (they get auto-joined!)
     cmdline_opts = ('autocall=i autoindent! automagic! banner! cache_size|cs=i '
                     'c=s classic|cl color_info! colors=s confirm_exit! '
                     'debug! deep_reload! editor=s log|l messages! nosep '
                     'object_info_string_level=i pdb! '
                     'pprint! prompt_in1|pi1=s prompt_in2|pi2=s prompt_out|po=s '
                     'pydb! '
                     'pylab_import_all! '
                     'quick screen_length|sl=i prompts_pad_left=i '
                     'logfile|lf=s logplay|lp=s profile|p=s '
                     'readline! readline_merge_completions! '
                     'readline_omit__names! '
                     'rcfile=s separate_in|si=s separate_out|so=s '
                     'separate_out2|so2=s xmode=s wildcards_case_sensitive! '
                     'magic_docstrings system_verbose! '
                     'multi_line_specials! '
                     'term_title! wxversion=s '
                     'autoedit_syntax!')
 
     # Options that can *only* appear at the cmd line (not in rcfiles).
     
     cmdline_only = ('help interact|i ipythondir=s Version upgrade '
                     'gthread! qthread! q4thread! wthread! tkthread! pylab! tk! '
                     # 'twisted!'  # disabled for now.
                     )
 
     # Build the actual name list to be used by DPyGetOpt
     opts_names = qw(cmdline_opts) + qw(cmdline_only)
 
     # Set sensible command line defaults.
     # This should have everything from  cmdline_opts and cmdline_only
     opts_def = Struct(autocall = 1,
                       autoedit_syntax = 0,
                       autoindent = 0,
                       automagic = 1,
                       autoexec = [],
                       banner = 1,
                       c = '',
                       cache_size = 1000,
                       classic = 0,
                       color_info = 0,
                       colors = 'NoColor',
                       confirm_exit = 1,
                       debug = 0,
                       deep_reload = 0,
                       editor = '0',
                       gthread = 0,
                       help = 0,
                       interact = 0,
                       ipythondir = ipythondir_def,
                       log = 0,
                       logfile = '',
                       logplay = '',
                       messages = 1,
                       multi_line_specials = 1,
                       nosep = 0,
                       object_info_string_level = 0,
                       pdb = 0,
                       pprint = 0,
                       profile = '',
                       prompt_in1 = 'In [\\#]: ',
                       prompt_in2 = '   .\\D.: ',
                       prompt_out = 'Out[\\#]: ',
                       prompts_pad_left = 1,
                       pydb = 0,
                       pylab = 0,
                       pylab_import_all = 1,
                       q4thread = 0,
                       qthread = 0,
                       quick = 0,
                       quiet = 0,
                       rcfile = 'ipythonrc' + rc_suffix,
                       readline = 1,
                       readline_merge_completions = 1,
                       readline_omit__names = 0,
                       screen_length = 0,
                       separate_in = '\n',
                       separate_out = '\n',
                       separate_out2 = '',
                       system_header = 'IPython system call: ',
                       system_verbose = 0,
                       term_title = 1,
                       tk = 0,
                       #twisted= 0,  # disabled for now
                       upgrade = 0,
                       Version = 0,
                       wildcards_case_sensitive = 1,
                       wthread = 0,
                       wxversion = '0',
                       xmode = 'Context',
                       magic_docstrings = 0,  # undocumented, for doc generation
                       )
     
     # Things that will *only* appear in rcfiles (not at the command line).
     # Make sure there's a space before each end of line (they get auto-joined!)
     rcfile_opts = { qwflat: 'include import_mod import_all execfile ',
                     qw_lol: 'import_some ',
                     # for things with embedded whitespace:
                     list_strings:'execute alias readline_parse_and_bind ',
                     # Regular strings need no conversion:
                     None:'readline_remove_delims ',
                     }
     # Default values for these
     rc_def = Struct(include = [],
                     import_mod = [], 
                     import_all = [],
                     import_some = [[]],
                     execute = [],
                     execfile = [],
                     alias = [],
                     readline_parse_and_bind = [],
                     readline_remove_delims = '',
                     )
 
     # Build the type conversion dictionary from the above tables:
     typeconv = rcfile_opts.copy()
     typeconv.update(optstr2types(cmdline_opts))
 
     # FIXME: the None key appears in both, put that back together by hand. Ugly!
     typeconv[None] += ' ' + rcfile_opts[None]
 
     # Remove quotes at ends of all strings (used to protect spaces)
     typeconv[unquote_ends] = typeconv[None]
     del typeconv[None]
 
     # Build the list we'll use to make all config decisions with defaults:
     opts_all = opts_def.copy()
     opts_all.update(rc_def)
 
     # Build conflict resolver for recursive loading of config files:
     # - preserve means the outermost file maintains the value, it is not
     # overwritten if an included file has the same key.
     # - add_flip applies + to the two values, so it better make sense to add
     # those types of keys. But it flips them first so that things loaded
     # deeper in the inclusion chain have lower precedence.
     conflict = {'preserve': ' '.join([ typeconv[int],
                                        typeconv[unquote_ends] ]),
                 'add_flip': ' '.join([ typeconv[qwflat],
                                        typeconv[qw_lol],
                                        typeconv[list_strings] ])
                 }
 
     # Now actually process the command line
     getopt = DPyGetOpt.DPyGetOpt()
     getopt.setIgnoreCase(0)
 
     getopt.parseConfiguration(opts_names)
 
     try:
         getopt.processArguments(argv)
     except DPyGetOpt.ArgumentError, exc:
         print cmd_line_usage
         warn('\nError in Arguments: "%s"' % exc)
         sys.exit(1)
 
     # convert the options dict to a struct for much lighter syntax later
     opts = Struct(getopt.optionValues)
     args = getopt.freeValues
 
     # this is the struct (which has default values at this point) with which
     # we make all decisions:
     opts_all.update(opts)
 
     # Options that force an immediate exit
     if opts_all.help:
         page(cmd_line_usage)
         sys.exit()
 
     if opts_all.Version:
         print release.version
         sys.exit()
 
     if opts_all.magic_docstrings:
         IP.magic_magic('-latex')
         sys.exit()
 
     # Display the deprecation warnings about threaded shells
     if opts_all.pylab == 1: threaded_shell_warning()
     if opts_all.wthread == 1: threaded_shell_warning()
     if opts_all.qthread == 1: threaded_shell_warning()
     if opts_all.q4thread == 1: threaded_shell_warning()
     if opts_all.gthread == 1: threaded_shell_warning()
 
     # add personal ipythondir to sys.path so that users can put things in
     # there for customization
     sys.path.append(os.path.abspath(opts_all.ipythondir))
 
     # Create user config directory if it doesn't exist. This must be done
     # *after* getting the cmd line options.
     if not os.path.isdir(opts_all.ipythondir):
         IP.user_setup(opts_all.ipythondir,rc_suffix,'install')
 
     # upgrade user config files while preserving a copy of the originals
     if opts_all.upgrade:
         IP.user_setup(opts_all.ipythondir,rc_suffix,'upgrade')
 
     # check mutually exclusive options in the *original* command line
     mutex_opts(opts,[qw('log logfile'),qw('rcfile profile'),
                      qw('classic profile'),qw('classic rcfile')])
 
     #---------------------------------------------------------------------------
     # Log replay
     
     # if -logplay, we need to 'become' the other session. That basically means
     # replacing the current command line environment with that of the old
     # session and moving on.
 
     # this is needed so that later we know we're in session reload mode, as
     # opts_all will get overwritten:
     load_logplay = 0
 
     if opts_all.logplay:
         load_logplay = opts_all.logplay 
         opts_debug_save = opts_all.debug
         try:
             logplay = open(opts_all.logplay)
         except IOError:
             if opts_all.debug: IP.InteractiveTB()
             warn('Could not open logplay file '+`opts_all.logplay`)
             # restore state as if nothing had happened and move on, but make
             # sure that later we don't try to actually load the session file
             logplay = None
             load_logplay = 0
             del opts_all.logplay
         else:
             try: 
                 logplay.readline()
                 logplay.readline();
                 # this reloads that session's command line
                 cmd = logplay.readline()[6:] 
                 exec cmd
                 # restore the true debug flag given so that the process of
                 # session loading itself can be monitored.
                 opts.debug = opts_debug_save
                 # save the logplay flag so later we don't overwrite the log
                 opts.logplay = load_logplay
                 # now we must update our own structure with defaults
                 opts_all.update(opts)
                 # now load args
                 cmd = logplay.readline()[6:] 
                 exec cmd
                 logplay.close()
             except:
                 logplay.close()
                 if opts_all.debug: IP.InteractiveTB()
                 warn("Logplay file lacking full configuration information.\n"
                      "I'll try to read it, but some things may not work.")
 
     #-------------------------------------------------------------------------
     # set up output traps: catch all output from files, being run, modules
     # loaded, etc. Then give it to the user in a clean form at the end.
     
     msg_out = 'Output messages. '
     msg_err = 'Error messages. '
     msg_sep = '\n'
     msg = Struct(config    = OutputTrap('Configuration Loader',msg_out,
                                         msg_err,msg_sep,debug,
                                         quiet_out=1),
                  user_exec = OutputTrap('User File Execution',msg_out,
                                         msg_err,msg_sep,debug),
                  logplay   = OutputTrap('Log Loader',msg_out,
                                         msg_err,msg_sep,debug),
                  summary = ''
                  )
 
     #-------------------------------------------------------------------------
     # Process user ipythonrc-type configuration files
 
     # turn on output trapping and log to msg.config
     # remember that with debug on, trapping is actually disabled
     msg.config.trap_all()
 
     # look for rcfile in current or default directory
     try:
         opts_all.rcfile = filefind(opts_all.rcfile,opts_all.ipythondir)
     except IOError:
         if opts_all.debug:  IP.InteractiveTB()
         warn('Configuration file %s not found. Ignoring request.'
              % (opts_all.rcfile) )
 
+    print opts_all.rcfile, opts_all.ipythondir
+
     # 'profiles' are a shorthand notation for config filenames
     profile_handled_by_legacy = False
     if opts_all.profile:
             
         try:
             opts_all.rcfile = filefind('ipythonrc-' + opts_all.profile
                                        + rc_suffix,
                                        opts_all.ipythondir)
             profile_handled_by_legacy = True
         except IOError:
            if opts_all.debug:  IP.InteractiveTB()
            opts.profile = ''  # remove profile from options if invalid
            # We won't warn anymore, primary method is ipy_profile_PROFNAME
            # which does trigger a warning.
 
     # load the config file
     rcfiledata = None
     if opts_all.quick:
         print 'Launching IPython in quick mode. No config file read.'
     elif opts_all.rcfile:
         try:
             cfg_loader = ConfigLoader(conflict)
             rcfiledata = cfg_loader.load(opts_all.rcfile,typeconv,
                                          'include',opts_all.ipythondir,
                                          purge = 1,
                                          unique = conflict['preserve'])
         except:
             IP.InteractiveTB()
             warn('Problems loading configuration file '+
                  `opts_all.rcfile`+
                  '\nStarting with default -bare bones- configuration.')
     else:
         warn('No valid configuration file found in either currrent directory\n'+
              'or in the IPython config. directory: '+`opts_all.ipythondir`+
              '\nProceeding with internal defaults.')
 
     #------------------------------------------------------------------------
     # Set exception handlers in mode requested by user.
     otrap = OutputTrap(trap_out=1)  # trap messages from magic_xmode
     IP.magic_xmode(opts_all.xmode)
     otrap.release_out()
 
     #------------------------------------------------------------------------
     # Execute user config
 
     # Create a valid config structure with the right precedence order:
     # defaults < rcfile < command line.  This needs to be in the instance, so
     # that method calls below that rely on it find it.
     IP.rc = rc_def.copy()
 
     # Work with a local alias inside this routine to avoid unnecessary
     # attribute lookups.
     IP_rc = IP.rc
     
     IP_rc.update(opts_def)
     if rcfiledata:
         IP_rc.update(rcfiledata)
     IP_rc.update(opts)
     if rc_override is not None:
         IP_rc.update(rc_override)
 
     # Store the original cmd line for reference:
     IP_rc.opts = opts
     IP_rc.args = args
 
     # create a *runtime* Struct like rc for holding parameters which may be
     # created and/or modified by runtime user extensions.
     IP.runtime_rc = Struct()
 
     # from this point on, all config should be handled through IP_rc,
     # opts* shouldn't be used anymore.
 
     
     # update IP_rc with some special things that need manual
     # tweaks. Basically options which affect other options. I guess this
     # should just be written so that options are fully orthogonal and we
     # wouldn't worry about this stuff!
 
     if IP_rc.classic:
         IP_rc.quick = 1
         IP_rc.cache_size = 0
         IP_rc.pprint = 0
         IP_rc.prompt_in1 = '>>> '
         IP_rc.prompt_in2 = '... '
         IP_rc.prompt_out = ''
         IP_rc.separate_in = IP_rc.separate_out = IP_rc.separate_out2 = '0'
         IP_rc.colors = 'NoColor'
         IP_rc.xmode = 'Plain'
 
     IP.pre_config_initialization()
     # configure readline
 
     # update exception handlers with rc file status
     otrap.trap_out()  # I don't want these messages ever.
     IP.magic_xmode(IP_rc.xmode)
     otrap.release_out()
 
     # activate logging if requested and not reloading a log
     if IP_rc.logplay:
         IP.magic_logstart(IP_rc.logplay + ' append')
     elif  IP_rc.logfile:
         IP.magic_logstart(IP_rc.logfile)
     elif IP_rc.log:
         IP.magic_logstart()
 
     # find user editor so that it we don't have to look it up constantly
     if IP_rc.editor.strip()=='0':
         try:
             ed = os.environ['EDITOR']
         except KeyError:
             if os.name == 'posix':
                 ed = 'vi'  # the only one guaranteed to be there!
             else:
                 ed = 'notepad' # same in Windows!
         IP_rc.editor = ed
 
     # Keep track of whether this is an embedded instance or not (useful for
     # post-mortems).
     IP_rc.embedded = IP.embedded
 
     # Recursive reload
     try:
         from IPython.lib import deepreload
         if IP_rc.deep_reload:
             __builtin__.reload = deepreload.reload
         else:
             __builtin__.dreload = deepreload.reload
         del deepreload
     except ImportError:
         pass
 
     # Save the current state of our namespace so that the interactive shell
     # can later know which variables have been created by us from config files
     # and loading. This way, loading a file (in any way) is treated just like
     # defining things on the command line, and %who works as expected.
 
     # DON'T do anything that affects the namespace beyond this point!
     IP.internal_ns.update(__main__.__dict__)
 
     #IP.internal_ns.update(locals()) # so our stuff doesn't show up in %who
 
     # Now run through the different sections of the users's config
     if IP_rc.debug:    
         print 'Trying to execute the following configuration structure:'
         print '(Things listed first are deeper in the inclusion tree and get'
         print 'loaded first).\n'
         pprint(IP_rc.__dict__)
         
     for mod in IP_rc.import_mod:
         try:
             exec 'import '+mod in IP.user_ns
         except :
             IP.InteractiveTB()
             import_fail_info(mod)
 
     for mod_fn in IP_rc.import_some:
         if not mod_fn == []: 
             mod,fn = mod_fn[0],','.join(mod_fn[1:])
             try:
                 exec 'from '+mod+' import '+fn in IP.user_ns
             except :
                 IP.InteractiveTB()
                 import_fail_info(mod,fn)
 
     for mod in IP_rc.import_all:
         try:
             exec 'from '+mod+' import *' in IP.user_ns
         except :
             IP.InteractiveTB()
             import_fail_info(mod)
 
     for code in IP_rc.execute:
         try:
             exec code in IP.user_ns
         except:
             IP.InteractiveTB()
             warn('Failure executing code: ' + `code`)
 
     # Execute the files the user wants in ipythonrc
     for file in IP_rc.execfile:
         try:
             file = filefind(file,sys.path+[IPython_dir])
         except IOError:
             warn(itpl('File $file not found. Skipping it.'))
         else:
             IP.safe_execfile(os.path.expanduser(file),IP.user_ns)
 
     # finally, try importing ipy_*_conf for final configuration
     try:
         import ipy_system_conf
     except ImportError:
         if opts_all.debug:  IP.InteractiveTB()
         warn("Could not import 'ipy_system_conf'")        
     except:
         IP.InteractiveTB()
         import_fail_info('ipy_system_conf')
 
     # only import prof module if ipythonrc-PROF was not found
     if opts_all.profile and not profile_handled_by_legacy:
         profmodname = 'ipy_profile_' + opts_all.profile
         try:
             force_import(profmodname)
         except:
             IP.InteractiveTB()
             print "Error importing",profmodname,\
                   "- perhaps you should run %upgrade?"
             import_fail_info(profmodname)
         else:
             opts.profile = opts_all.profile
     else:
         force_import('ipy_profile_none')
     # XXX - this is wrong: ipy_user_conf should not be loaded unconditionally,
     # since the user could have specified a config file path by hand.
     try:
         force_import('ipy_user_conf')
     except:
         conf = opts_all.ipythondir + "/ipy_user_conf.py"
         IP.InteractiveTB()
         if not os.path.isfile(conf):
             warn(conf + ' does not exist, please run %upgrade!')
 
         import_fail_info("ipy_user_conf")
 
     # Define the history file for saving commands in between sessions
     try:
         histfname = 'history-%s' % opts.profile
     except AttributeError:
         histfname = 'history'
     IP.histfile = os.path.join(opts_all.ipythondir,histfname)
 
     # finally, push the argv to options again to ensure highest priority
     IP_rc.update(opts)
     
     # release stdout and stderr and save config log into a global summary
     msg.config.release_all()
     if IP_rc.messages:
         msg.summary += msg.config.summary_all()
 
     #------------------------------------------------------------------------
     # Setup interactive session
 
     # Now we should be fully configured. We can then execute files or load
     # things only needed for interactive use. Then we'll open the shell.
 
     # Take a snapshot of the user namespace before opening the shell. That way
     # we'll be able to identify which things were interactively defined and
     # which were defined through config files.
     IP.user_config_ns.update(IP.user_ns)
 
     # Force reading a file as if it were a session log. Slower but safer.
     if load_logplay:
         print 'Replaying log...'
         try:
             if IP_rc.debug:
                 logplay_quiet = 0
             else:
                  logplay_quiet = 1
 
             msg.logplay.trap_all()
             IP.safe_execfile(load_logplay,IP.user_ns,
                              islog = 1, quiet = logplay_quiet)
             msg.logplay.release_all()
             if IP_rc.messages:
                 msg.summary += msg.logplay.summary_all()
         except:
             warn('Problems replaying logfile %s.' % load_logplay)
             IP.InteractiveTB()
 
     # Load remaining files in command line
     msg.user_exec.trap_all()
 
     # Do NOT execute files named in the command line as scripts to be loaded
     # by embedded instances.  Doing so has the potential for an infinite
     # recursion if there are exceptions thrown in the process.
 
     # XXX FIXME: the execution of user files should be moved out to after
     # ipython is fully initialized, just as if they were run via %run at the
     # ipython prompt.  This would also give them the benefit of ipython's
     # nice tracebacks.
 
     if (not embedded and IP_rc.args and 
         not IP_rc.args[0].lower().endswith('.ipy')):
         name_save = IP.user_ns['__name__']
         IP.user_ns['__name__'] = '__main__'
         # Set our own excepthook in case the user code tries to call it
         # directly. This prevents triggering the IPython crash handler.
         old_excepthook,sys.excepthook = sys.excepthook, IP.excepthook
 
         save_argv = sys.argv[1:] # save it for later restoring
         
         sys.argv = args
         
         try:
             IP.safe_execfile(args[0], IP.user_ns)
         finally:
             # Reset our crash handler in place
             sys.excepthook = old_excepthook
             sys.argv[:] = save_argv
             IP.user_ns['__name__'] = name_save
         
     msg.user_exec.release_all()
 
     if IP_rc.messages:
         msg.summary += msg.user_exec.summary_all()
 
     # since we can't specify a null string on the cmd line, 0 is the equivalent:
     if IP_rc.nosep:
         IP_rc.separate_in = IP_rc.separate_out = IP_rc.separate_out2 = '0'
     if IP_rc.separate_in == '0': IP_rc.separate_in = ''
     if IP_rc.separate_out == '0': IP_rc.separate_out = ''
     if IP_rc.separate_out2 == '0': IP_rc.separate_out2 = ''
     IP_rc.separate_in = IP_rc.separate_in.replace('\\n','\n')
     IP_rc.separate_out = IP_rc.separate_out.replace('\\n','\n')
     IP_rc.separate_out2 = IP_rc.separate_out2.replace('\\n','\n')
 
     # Determine how many lines at the bottom of the screen are needed for
     # showing prompts, so we can know wheter long strings are to be printed or
     # paged:
     num_lines_bot = IP_rc.separate_in.count('\n')+1
     IP_rc.screen_length = IP_rc.screen_length - num_lines_bot
 
     # configure startup banner
     if IP_rc.c:  # regular python doesn't print the banner with -c
         IP_rc.banner = 0
     if IP_rc.banner:
         BANN_P = IP.BANNER_PARTS
     else:
         BANN_P = []
 
     if IP_rc.profile: BANN_P.append('IPython profile: %s\n' % IP_rc.profile)
 
     # add message log (possibly empty)
     if msg.summary: BANN_P.append(msg.summary)
     # Final banner is a string
     IP.BANNER = '\n'.join(BANN_P)
 
     # Finalize the IPython instance.  This assumes the rc structure is fully
     # in place.
     IP.post_config_initialization()
 
     return IP
 #************************ end of file <ipmaker.py> **************************

IPython/utils/genutils.py

@@ -1,2261 +1,2284 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.
 """
 
 #*****************************************************************************
 #       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.
 #*****************************************************************************
 
 #****************************************************************************
 # required modules from the Python standard library
 import __main__
 import commands
 try:
     import doctest
 except ImportError:
     pass
 import os
 import platform
 import re
 import shlex
 import shutil
 import subprocess
 import sys
 import tempfile
 import time
 import types
 import warnings
 
 # Curses and termios are Unix-only modules
 try:
     import curses
     # We need termios as well, so if its import happens to raise, we bail on
     # using curses altogether.
     import termios
 except ImportError:
     USE_CURSES = False
 else:
     # Curses on Solaris may not be complete, so we can't use it there
     USE_CURSES = hasattr(curses,'initscr')
 
 # Other IPython utilities
 import IPython
 from IPython.external.Itpl import Itpl,itpl,printpl
 from IPython.utils import platutils
 from IPython.utils import DPyGetOpt
 from IPython.utils.generics import result_display
 from IPython.core import ipapi
 from IPython.external.path import path
 if os.name == "nt":
     from IPython.utils.winconsole import get_console_size
 
 try:
     set
 except:
     from sets import Set as set
 
 
 #****************************************************************************
 # 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.utils.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
 
 def abbrev_cwd():
     """ Return abbreviated version of cwd, e.g. d:mydir """
     cwd = os.getcwd().replace('\\','/')
     drivepart = ''
     tail = cwd
     if sys.platform == 'win32':
         if len(cwd) < 4:
             return cwd
         drivepart,tail = os.path.splitdrive(cwd)
 
 
     parts = tail.split('/')
     if len(parts) > 2:
         tail = '/'.join(parts[-2:])
 
     return (drivepart + (
         cwd == '/' and '/' or tail))
 
 
 # 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 " + abbrev_cwd())
 
 # 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: ')
     """
 
     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."""
+def filefind(filename, path_dirs=None):
+    """Find a file by looking through a sequence of paths.
 
-    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
+    This iterates through a sequence of paths looking for a file and returns
+    the full, absolute path of the first occurence of the file.  If no set of
+    path dirs is given, the filename is tested as is, after running through
+    :func:`expandvars` and :func:`expanduser`.  Thus a simple call::
+
+        filefind('myfile.txt')
+
+    will find the file in the current working dir, but::
+
+        filefind('~/myfile.txt')
+
+    Will find the file in the users home directory.  This function does not
+    automatically try any paths, such as the cwd or the user's home directory.
+    
+    Parameters
+    ----------
+    filename : str
+        The filename to look for.
+    path_dirs : str, None or sequence of str
+        The sequence of paths to look for the file in.  If None, the filename
+        need to be absolute or be in the cwd.  If a string, the string is
+        put into a sequence and the searched.  If a sequence, walk through
+        each element and join with ``filename``, calling :func:`expandvars`
+        and :func:`expanduser` before testing for existence.
+        
+    Returns
+    -------
+    Raises :exc:`IOError` or returns absolute path to file.
+    """
+    if path_dirs is None:
+        path_dirs = ("",)
+    elif isinstance(path_dirs, basestring):
+        path_dirs = (path_dirs,)
+    for path in path_dirs:
+        if path == '.': path = os.getcwd()
+        testname = os.path.expandvars(
+                       os.path.expanduser(
+                           os.path.join(path, filename)))
         if os.path.isfile(testname):
-            return testname
-    raise IOError,'File' + `fname` + \
-          ' not found in current or supplied directories:' + `alt_dirs`
+            return os.path.abspath(testname)
+    raise IOError("File does not exist in any "
+                  "of the search paths: %r, %r" % \
+                  (filename, path_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 DPyGetOpt.ArgumentError, exc:
         print usage
         warn('"%s"' % exc,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):
     r"""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 contains (we put it in a string to keep the test
     self-contained):
 
     >>> test_ini = '''\
     ... i 3
     ... x 4.5
     ... y 5.5
     ... s hi ho'''
 
     Then we can use it as follows:
     >>> type_conv={int:'i',float:'x',None:'s'}
 
     >>> d = read_dict(test_ini)
 
     >>> sorted(d.items())
     [('i', '3'), ('s', 'hi ho'), ('x', '4.5'), ('y', '5.5')]
 
     >>> d = read_dict(test_ini,type_conv)
 
     >>> sorted(d.items())
     [('i', 3), ('s', 'hi ho'), ('x', 4.5), ('y', '5.5')]
 
     >>> d = read_dict(test_ini,type_conv,purge=True)
 
     >>> sorted(d.items())
     [('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
     if '\n' in filename:
         lines = filename.splitlines()
         file = None
     else:
         file = open(filename,'r')
         lines = file.readlines()
     for line in lines:
         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
 
 #----------------------------------------------------------------------------
 def dhook_wrap(func,*a,**k):
     """Wrap a function call in a sys.displayhook controller.
 
     Returns a wrapper around func which calls func, with all its arguments and
     keywords unmodified, using the default sys.displayhook.  Since IPython
     modifies sys.displayhook, it breaks the behavior of certain systems that
     rely on the default behavior, notably doctest.
     """
 
     def f(*a,**k):
 
         dhook_s = sys.displayhook
         sys.displayhook = sys.__displayhook__
         try:
             out = func(*a,**k)
         finally:
             sys.displayhook = dhook_s
 
         return out
 
     f.__doc__ = func.__doc__
     return f
 
 #----------------------------------------------------------------------------
 def doctest_reload():
     """Properly reload doctest to reuse it interactively.
 
     This routine:
 
       - imports doctest but does NOT reload it (see below).
 
       - resets its global 'master' attribute to None, so that multiple uses of
       the module interactively don't produce cumulative reports.
 
       - Monkeypatches its core test runner method to protect it from IPython's
       modified displayhook.  Doctest expects the default displayhook behavior
       deep down, so our modification breaks it completely.  For this reason, a
       hard monkeypatch seems like a reasonable solution rather than asking
       users to manually use a different doctest runner when under IPython.
 
     Notes
     -----
 
     This function *used to* reload doctest, but this has been disabled because
     reloading doctest unconditionally can cause massive breakage of other
     doctest-dependent modules already in memory, such as those for IPython's
     own testing system.  The name wasn't changed to avoid breaking people's
     code, but the reload call isn't actually made anymore."""
 
     import doctest
     doctest.master = None
     doctest.DocTestRunner.run = dhook_wrap(doctest.DocTestRunner.run)
 
 #----------------------------------------------------------------------------
 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 hasattr(sys, "frozen"): #Is frozen by py2exe
         if '\\library.zip\\' in IPython.__file__.lower():#libraries compressed to zip-file
             root, rest = IPython.__file__.lower().split('library.zip')
         else: 
             root=os.path.join(os.path.split(IPython.__file__)[0],"../../")
         root=os.path.abspath(root).rstrip('\\')
         if isdir(os.path.join(root, '_ipython')):
             os.environ["IPYKITROOT"] = root
         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 KeyError:
                 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.'
 
 
 def get_ipython_dir():
     """Get the IPython directory for this platform and user.
     
     This uses the logic in `get_home_dir` to find the home directory
     and the adds either .ipython or _ipython to the end of the path.
     """
     if os.name == 'posix':
          ipdir_def = '.ipython'
     else:
          ipdir_def = '_ipython'
     home_dir = get_home_dir()
     ipdir = os.path.abspath(os.environ.get('IPYTHONDIR',
                                            os.path.join(home_dir, ipdir_def)))
     return ipdir.decode(sys.getfilesystemencoding())
 
 def get_security_dir():
     """Get the IPython security directory.
     
     This directory is the default location for all security related files,
     including SSL/TLS certificates and FURL files.
     
     If the directory does not exist, it is created with 0700 permissions.
     If it exists, permissions are set to 0700.
     """
     security_dir = os.path.join(get_ipython_dir(), 'security')
     if not os.path.isdir(security_dir):
         os.mkdir(security_dir, 0700)
     else:
         os.chmod(security_dir, 0700)
     return security_dir
 
 def get_log_dir():
     """Get the IPython log directory.
     
     If the log directory does not exist, it is created.
     """
     log_dir = os.path.join(get_ipython_dir(), 'log')
     if not os.path.isdir(log_dir):
         os.mkdir(log_dir, 0777)
     return log_dir
 
 #****************************************************************************
 # 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 grep(self, pattern, prune = False, field = None):
         """ Return all strings matching 'pattern' (a regex or callable)
 
         This is case-insensitive. If prune is true, return all items
         NOT matching the pattern.
 
         If field is specified, the match must occur in the specified
         whitespace-separated field.
 
         Examples::
 
             a.grep( lambda x: x.startswith('C') )
             a.grep('Cha.*log', prune=1)
             a.grep('chm', field=-1)
         """
 
         def match_target(s):
             if field is None:
                 return s
             parts = s.split()
             try:
                 tgt = parts[field]
                 return tgt
             except IndexError:
                 return ""
 
         if isinstance(pattern, basestring):
             pred = lambda x : re.search(pattern, x, re.IGNORECASE)
         else:
             pred = pattern
         if not prune:
             return SList([el for el in self if pred(match_target(el))])
         else:
             return SList([el for el in self if not pred(match_target(el))])
     def fields(self, *fields):
         """ Collect whitespace-separated fields from string list
 
         Allows quick awk-like usage of string lists.
 
         Example data (in var a, created by 'a = !ls -l')::
             -rwxrwxrwx  1 ville None      18 Dec 14  2006 ChangeLog
             drwxrwxrwx+ 6 ville None       0 Oct 24 18:05 IPython
 
         a.fields(0) is ['-rwxrwxrwx', 'drwxrwxrwx+']
         a.fields(1,0) is ['1 -rwxrwxrwx', '6 drwxrwxrwx+']
         (note the joining by space).
         a.fields(-1) is ['ChangeLog', 'IPython']
 
         IndexErrors are ignored.
 
         Without args, fields() just split()'s the strings.
         """
         if len(fields) == 0:
             return [el.split() for el in self]
 
         res = SList()
         for el in [f.split() for f in self]:
             lineparts = []
 
             for fd in fields:
                 try:
                     lineparts.append(el[fd])
                 except IndexError:
                     pass
             if lineparts:
                 res.append(" ".join(lineparts))
 
         return res
     def sort(self,field= None,  nums = False):
         """ sort by specified fields (see fields())
 
         Example::
             a.sort(1, nums = True)
 
         Sorts a by second field, in numerical order (so that 21 > 3)
 
         """
 
         #decorate, sort, undecorate
         if field is not None:
             dsu = [[SList([line]).fields(field),  line] for line in self]
         else:
             dsu = [[line,  line] for line in self]
         if nums:
             for i in range(len(dsu)):
                 numstr = "".join([ch for ch in dsu[i][0] if ch.isdigit()])
                 try:
                     n = int(numstr)
                 except ValueError:
                     n = 0;
                 dsu[i][0] = n
 
 
         dsu.sort()
         return SList([t[1] for t in dsu])
 
 def print_slist(arg):
     """ Prettier (non-repr-like) and more informative printer for SList """
     print "SList (.p, .n, .l, .s, .grep(), .fields(), sort() available):"
     if hasattr(arg,  'hideonce') and arg.hideonce:
         arg.hideonce = False
         return
 
     nlprint(arg)
 
 print_slist = result_display.when_type(SList)(print_slist)
 
 
 
 #----------------------------------------------------------------------------
 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.
 
     XXX - example removed because it caused encoding errors in documentation
     generation.  We need a new example that doesn't contain invalid chars.
 
     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 = 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 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()
     Python 2.1 rules!
     """
 
     # 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 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.
     """
 
     # Some routines may auto-compute start offsets incorrectly and pass a
     # negative value.  Offset to 0 for robustness.
     start = max(0,start)
 
     # first, try the hook
     ip = ipapi.get()
     if ip:
         try:
             ip.IP.hooks.show_in_pager(strng)
             return
         except ipapi.TryNext:
             pass
 
     # 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':
             use_curses = USE_CURSES
         else:
             # curses causes problems on many terminals other than xterm.
             use_curses = False
         if use_curses:
             # There is a bug in curses, where *sometimes* it fails to properly
             # initialize, and then after the endwin() call is made, the
             # terminal is left in an unusable state.  Rather than trying to
             # check everytime for this (by requesting and comparing termios
             # flags each time), we just save the initial terminal state and
             # unconditionally reset it every time.  It's cheaper than making
             # the checks.
             term_flags = termios.tcgetattr(sys.stdout)
             scr = curses.initscr()
             screen_lines_real,screen_cols = scr.getmaxyx()
             curses.endwin()
             # Restore terminal state in case endwin() didn't.
             termios.tcsetattr(sys.stdout,termios.TCSANOW,term_flags)
             # Now we have what we needed: the screen size in rows/columns
             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 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
 
 
 def _num_cpus_unix():
     """Return the number of active CPUs on a Unix system."""
     return os.sysconf("SC_NPROCESSORS_ONLN")
 
 
 def _num_cpus_darwin():
     """Return the number of active CPUs on a Darwin system."""
     p = subprocess.Popen(['sysctl','-n','hw.ncpu'],stdout=subprocess.PIPE)
     return p.stdout.read()
 
 
 def _num_cpus_windows():
     """Return the number of active CPUs on a Windows system."""
     return os.environ.get("NUMBER_OF_PROCESSORS")
 
 
 def num_cpus():
    """Return the effective number of CPUs in the system as an integer.
 
    This cross-platform function makes an attempt at finding the total number of
    available CPUs in the system, as returned by various underlying system and
    python calls.
 
    If it can't find a sensible answer, it returns 1 (though an error *may* make
    it return a large positive number that's actually incorrect).
    """
 
    # Many thanks to the Parallel Python project (http://www.parallelpython.com)
    # for the names of the keys we needed to look up for this function.  This
    # code was inspired by their equivalent function.
 
    ncpufuncs = {'Linux':_num_cpus_unix,
                 'Darwin':_num_cpus_darwin,
                 'Windows':_num_cpus_windows,
                 # On Vista, python < 2.5.2 has a bug and returns 'Microsoft'
                 # See http://bugs.python.org/issue1082 for details.
                 'Microsoft':_num_cpus_windows,
                 }
 
    ncpufunc = ncpufuncs.get(platform.system(),
                             # default to unix version (Solaris, AIX, etc)
                             _num_cpus_unix)
 
    try:
        ncpus = max(1,int(ncpufunc()))
    except:
        ncpus = 1
    return ncpus
 
 def extract_vars(*names,**kw):
     """Extract a set of variables by name from another frame.
 
     :Parameters:
       - `*names`: strings
         One or more variable names which will be extracted from the caller's
     frame.
 
     :Keywords:
       - `depth`: integer (0)
         How many frames in the stack to walk when looking for your variables.
 
 
     Examples:
 
         In [2]: def func(x):
            ...:     y = 1
            ...:     print extract_vars('x','y')
            ...:
 
         In [3]: func('hello')
         {'y': 1, 'x': 'hello'}
     """
 
     depth = kw.get('depth',0)
     
     callerNS = sys._getframe(depth+1).f_locals
     return dict((k,callerNS[k]) for k in names)
     
 
 def extract_vars_above(*names):
     """Extract a set of variables by name from another frame.
 
     Similar to extractVars(), but with a specified depth of 1, so that names
     are exctracted exactly from above the caller.
 
     This is simply a convenience function so that the very common case (for us)
     of skipping exactly 1 frame doesn't have to construct a special dict for
     keyword passing."""
 
     callerNS = sys._getframe(2).f_locals
     return dict((k,callerNS[k]) for k in names)
 
 def shexp(s):
     """Expand $VARS and ~names in a string, like a shell
 
     :Examples:
     
        In [2]: os.environ['FOO']='test'
 
        In [3]: shexp('variable FOO is $FOO')
        Out[3]: 'variable FOO is test'
     """
     return os.path.expandvars(os.path.expanduser(s))
     
 
 def list_strings(arg):
     """Always return a list of strings, given a string or list of strings
     as input.
 
     :Examples:
 
         In [7]: list_strings('A single string')
         Out[7]: ['A single string']
 
         In [8]: list_strings(['A single string in a list'])
         Out[8]: ['A single string in a list']
 
         In [9]: list_strings(['A','list','of','strings'])
         Out[9]: ['A', 'list', 'of', 'strings']
     """
 
     if isinstance(arg,basestring): return [arg]
     else: return arg
 
 def marquee(txt='',width=78,mark='*'):
     """Return the input string centered in a 'marquee'.
 
     :Examples:
 
         In [16]: marquee('A test',40)
         Out[16]: '**************** A test ****************'
 
         In [17]: marquee('A test',40,'-')
         Out[17]: '---------------- A test ----------------'
 
         In [18]: marquee('A test',40,' ')
         Out[18]: '                 A test                 '
 
     """
     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)
 
 #*************************** end of file <genutils.py> **********************

IPython/utils/tests/test_traitlets.py

@@ -1,667 +1,670 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 Tests for IPython.utils.traitlets.
 
 Authors:
 
 * Brian Granger
 * Enthought, Inc.  Some of the code in this file comes from enthought.traits
   and is licensed under the BSD license.  Also, many of the ideas also come
   from enthought.traits even though our implementation is very different.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import sys
 import os
 
 
 from unittest import TestCase
 
 from IPython.utils.traitlets import (
     HasTraitlets, MetaHasTraitlets, TraitletType, Any,
     Int, Long, Float, Complex, Str, Unicode, Bool, TraitletError,
     Undefined, Type, This, Instance
 )
 
 
 #-----------------------------------------------------------------------------
 # Helper classes for testing
 #-----------------------------------------------------------------------------
 
 
 class HasTraitletsStub(HasTraitlets):
 
     def _notify_traitlet(self, name, old, new):
         self._notify_name = name
         self._notify_old = old
         self._notify_new = new
 
 
 #-----------------------------------------------------------------------------
 # Test classes
 #-----------------------------------------------------------------------------
 
 
 class TestTraitletType(TestCase):
 
     def test_get_undefined(self):
         class A(HasTraitlets):
             a = TraitletType
         a = A()
         self.assertEquals(a.a, Undefined)
 
     def test_set(self):
         class A(HasTraitletsStub):
             a = TraitletType
 
         a = A()
         a.a = 10
         self.assertEquals(a.a, 10)
         self.assertEquals(a._notify_name, 'a')
         self.assertEquals(a._notify_old, Undefined)
         self.assertEquals(a._notify_new, 10)
 
     def test_validate(self):
         class MyTT(TraitletType):
             def validate(self, inst, value):
                 return -1
         class A(HasTraitletsStub):
             tt = MyTT
         
         a = A()
         a.tt = 10
         self.assertEquals(a.tt, -1)
 
     def test_default_validate(self):
         class MyIntTT(TraitletType):
             def validate(self, obj, value):
                 if isinstance(value, int):
                     return value
                 self.error(obj, value)
         class A(HasTraitlets):
             tt = MyIntTT(10)
         a = A()
         self.assertEquals(a.tt, 10)
 
         # Defaults are validated when the HasTraitlets is instantiated
         class B(HasTraitlets):
             tt = MyIntTT('bad default')
         self.assertRaises(TraitletError, B)
 
     def test_is_valid_for(self):
         class MyTT(TraitletType):
             def is_valid_for(self, value):
                 return True
         class A(HasTraitlets):
             tt = MyTT
 
         a = A()
         a.tt = 10
         self.assertEquals(a.tt, 10)
 
     def test_value_for(self):
         class MyTT(TraitletType):
             def value_for(self, value):
                 return 20
         class A(HasTraitlets):
             tt = MyTT
 
         a = A()
         a.tt = 10
         self.assertEquals(a.tt, 20)
 
     def test_info(self):
         class A(HasTraitlets):
             tt = TraitletType
         a = A()
         self.assertEquals(A.tt.info(), 'any value')
 
     def test_error(self):
         class A(HasTraitlets):
             tt = TraitletType
         a = A()
         self.assertRaises(TraitletError, A.tt.error, a, 10)
 
 
 class TestHasTraitletsMeta(TestCase):
 
     def test_metaclass(self):
         self.assertEquals(type(HasTraitlets), MetaHasTraitlets)
 
         class A(HasTraitlets):
             a = Int
 
         a = A()
         self.assertEquals(type(a.__class__), MetaHasTraitlets)
         self.assertEquals(a.a,0)
         a.a = 10
         self.assertEquals(a.a,10)
 
         class B(HasTraitlets):
             b = Int()
 
         b = B()
         self.assertEquals(b.b,0)
         b.b = 10
         self.assertEquals(b.b,10)
 
         class C(HasTraitlets):
             c = Int(30)
 
         c = C()
         self.assertEquals(c.c,30)
         c.c = 10
         self.assertEquals(c.c,10)
 
     def test_this_class(self):
         class A(HasTraitlets):
             t = This()
             tt = This()
         class B(A):
             tt = This()
             ttt = This()
         self.assertEquals(A.t.this_class, A)
         self.assertEquals(B.t.this_class, A)
         self.assertEquals(B.tt.this_class, B)
         self.assertEquals(B.ttt.this_class, B)
 
 class TestHasTraitletsNotify(TestCase):
 
     def setUp(self):
         self._notify1 = []
         self._notify2 = []
 
     def notify1(self, name, old, new):
         self._notify1.append((name, old, new))
 
     def notify2(self, name, old, new):
         self._notify2.append((name, old, new))
 
     def test_notify_all(self):
 
         class A(HasTraitlets):
             a = Int
             b = Float
 
         a = A()
         a.on_traitlet_change(self.notify1)
         a.a = 0
         self.assertEquals(len(self._notify1),0)
         a.b = 0.0
         self.assertEquals(len(self._notify1),0)
         a.a = 10
         self.assert_(('a',0,10) in self._notify1)
         a.b = 10.0
         self.assert_(('b',0.0,10.0) in self._notify1)
         self.assertRaises(TraitletError,setattr,a,'a','bad string')
         self.assertRaises(TraitletError,setattr,a,'b','bad string')
         self._notify1 = []
         a.on_traitlet_change(self.notify1,remove=True)
         a.a = 20
         a.b = 20.0
         self.assertEquals(len(self._notify1),0)
 
     def test_notify_one(self):
 
         class A(HasTraitlets):
             a = Int
             b = Float
 
         a = A()
         a.on_traitlet_change(self.notify1, 'a')
         a.a = 0
         self.assertEquals(len(self._notify1),0)
         a.a = 10
         self.assert_(('a',0,10) in self._notify1)
         self.assertRaises(TraitletError,setattr,a,'a','bad string')
 
     def test_subclass(self):
 
         class A(HasTraitlets):
             a = Int
 
         class B(A):
             b = Float
 
         b = B()
         self.assertEquals(b.a,0)
         self.assertEquals(b.b,0.0)
         b.a = 100
         b.b = 100.0
         self.assertEquals(b.a,100)
         self.assertEquals(b.b,100.0)
 
     def test_notify_subclass(self):
 
         class A(HasTraitlets):
             a = Int
 
         class B(A):
             b = Float
 
         b = B()
         b.on_traitlet_change(self.notify1, 'a')
         b.on_traitlet_change(self.notify2, 'b')
         b.a = 0
         b.b = 0.0
         self.assertEquals(len(self._notify1),0)
         self.assertEquals(len(self._notify2),0)
         b.a = 10
         b.b = 10.0
         self.assert_(('a',0,10) in self._notify1)
         self.assert_(('b',0.0,10.0) in self._notify2)
 
     def test_static_notify(self):
 
         class A(HasTraitlets):
             a = Int
             _notify1 = []
             def _a_changed(self, name, old, new):
                 self._notify1.append((name, old, new))
 
         a = A()
         a.a = 0
         # This is broken!!!
         self.assertEquals(len(a._notify1),0)
         a.a = 10
         self.assert_(('a',0,10) in a._notify1)
 
         class B(A):
             b = Float
             _notify2 = []
             def _b_changed(self, name, old, new):
                 self._notify2.append((name, old, new))
 
         b = B()
         b.a = 10
         b.b = 10.0
         self.assert_(('a',0,10) in b._notify1)
         self.assert_(('b',0.0,10.0) in b._notify2)
 
     def test_notify_args(self):
 
         def callback0():
             self.cb = ()
         def callback1(name):
             self.cb = (name,)
         def callback2(name, new):
             self.cb = (name, new)
         def callback3(name, old, new):
             self.cb = (name, old, new)
 
         class A(HasTraitlets):
             a = Int
 
         a = A()
         a.on_traitlet_change(callback0, 'a')
         a.a = 10
         self.assertEquals(self.cb,())
         a.on_traitlet_change(callback0, 'a', remove=True)
 
         a.on_traitlet_change(callback1, 'a')
         a.a = 100
         self.assertEquals(self.cb,('a',))
         a.on_traitlet_change(callback1, 'a', remove=True)
 
         a.on_traitlet_change(callback2, 'a')
         a.a = 1000
         self.assertEquals(self.cb,('a',1000))
         a.on_traitlet_change(callback2, 'a', remove=True)
 
         a.on_traitlet_change(callback3, 'a')
         a.a = 10000
         self.assertEquals(self.cb,('a',1000,10000))
         a.on_traitlet_change(callback3, 'a', remove=True)
 
         self.assertEquals(len(a._traitlet_notifiers['a']),0)
 
 
 class TestHasTraitlets(TestCase):
 
     def test_traitlet_names(self):
         class A(HasTraitlets):
             i = Int
             f = Float
         a = A()
         self.assertEquals(a.traitlet_names(),['i','f'])
 
     def test_traitlet_metadata(self):
         class A(HasTraitlets):
             i = Int(config_key='MY_VALUE')
         a = A()
         self.assertEquals(a.traitlet_metadata('i','config_key'), 'MY_VALUE')
 
     def test_traitlets(self):
         class A(HasTraitlets):
             i = Int
             f = Float
         a = A()
         self.assertEquals(a.traitlets(), dict(i=A.i, f=A.f))
 
     def test_traitlets_metadata(self):
         class A(HasTraitlets):
             i = Int(config_key='VALUE1', other_thing='VALUE2')
             f = Float(config_key='VALUE3', other_thing='VALUE2')
         a = A()
-        # traitlets = a.traitlets(config_key=lambda v: True)
-        # self.assertEquals(traitlets, dict(i=A.i, f=A.f))
+        self.assertEquals(a.traitlets(), dict(i=A.i, f=A.f))
+        traitlets = a.traitlets(config_key=lambda v: True)
+        self.assertEquals(traitlets, dict(i=A.i, f=A.f))
         traitlets = a.traitlets(config_key='VALUE1', other_thing='VALUE2')
         self.assertEquals(traitlets, dict(i=A.i))
+        traitlets = a.traitlets('config_key')
+        self.assertEquals(traitlets, dict(i=A.i, f=A.f))
 
 #-----------------------------------------------------------------------------
 # Tests for specific traitlet types
 #-----------------------------------------------------------------------------
 
 
 class TestType(TestCase):
 
     def test_default(self):
 
         class B(object): pass
         class A(HasTraitlets):
             klass = Type
 
         a = A()
         self.assertEquals(a.klass, None)
         a.klass = B
         self.assertEquals(a.klass, B)
         self.assertRaises(TraitletError, setattr, a, 'klass', 10)
 
     def test_value(self):
 
         class B(object): pass
         class C(object): pass
         class A(HasTraitlets):
             klass = Type(B)
         
         a = A()
         self.assertEquals(a.klass, B)
         self.assertRaises(TraitletError, setattr, a, 'klass', C)
         self.assertRaises(TraitletError, setattr, a, 'klass', object)
         a.klass = B
 
     def test_allow_none(self):
 
         class B(object): pass
         class C(B): pass
         class A(HasTraitlets):
             klass = Type(B, allow_none=False)
 
         a = A()
         self.assertEquals(a.klass, B)
         self.assertRaises(TraitletError, setattr, a, 'klass', None)
         a.klass = C
         self.assertEquals(a.klass, C)
 
     def test_validate_klass(self):
 
         def inner():
             class A(HasTraitlets):
                 klass = Type('no strings allowed')
 
         self.assertRaises(TraitletError, inner)
 
     def test_validate_default(self):
 
         class B(object): pass
         class A(HasTraitlets):
             klass = Type('bad default', B)
 
         self.assertRaises(TraitletError, A)
 
         class C(HasTraitlets):
             klass = Type(None, B, allow_none=False)
 
         self.assertRaises(TraitletError, C)
 
 class TestInstance(TestCase):
 
     def test_basic(self):
         class Foo(object): pass
         class Bar(Foo): pass
         class Bah(object): pass
         
         class A(HasTraitlets):
             inst = Instance(Foo)
 
         a = A()
         self.assert_(a.inst is None)
         a.inst = Foo()
         self.assert_(isinstance(a.inst, Foo))
         a.inst = Bar()
         self.assert_(isinstance(a.inst, Foo))
         self.assertRaises(TraitletError, setattr, a, 'inst', Foo)
         self.assertRaises(TraitletError, setattr, a, 'inst', Bar)
         self.assertRaises(TraitletError, setattr, a, 'inst', Bah())
 
     def test_unique_default_value(self):
         class Foo(object): pass        
         class A(HasTraitlets):
             inst = Instance(Foo,(),{})
 
         a = A()
         b = A()
         self.assert_(a.inst is not b.inst)
 
     def test_args_kw(self):
         class Foo(object):
             def __init__(self, c): self.c = c
         class Bar(object): pass
         class Bah(object):
             def __init__(self, c, d):
                 self.c = c; self.d = d
 
         class A(HasTraitlets):
             inst = Instance(Foo, (10,))
         a = A()
         self.assertEquals(a.inst.c, 10)
 
         class B(HasTraitlets):
             inst = Instance(Bah, args=(10,), kw=dict(d=20))
         b = B()
         self.assertEquals(b.inst.c, 10)
         self.assertEquals(b.inst.d, 20)
 
         class C(HasTraitlets):
             inst = Instance(Foo)
         c = C()
         self.assert_(c.inst is None)
 
     def test_bad_default(self):
         class Foo(object): pass
 
         class A(HasTraitlets):
             inst = Instance(Foo, allow_none=False)
         
         self.assertRaises(TraitletError, A)
 
     def test_instance(self):
         class Foo(object): pass
 
         def inner():
             class A(HasTraitlets):
                 inst = Instance(Foo())
         
         self.assertRaises(TraitletError, inner)
 
 
 class TestThis(TestCase):
 
     def test_this_class(self):
         class Foo(HasTraitlets):
             this = This
 
         f = Foo()
         self.assertEquals(f.this, None)
         g = Foo()
         f.this = g
         self.assertEquals(f.this, g)
         self.assertRaises(TraitletError, setattr, f, 'this', 10)
 
     def test_this_inst(self):
         class Foo(HasTraitlets):
             this = This()
         
         f = Foo()
         f.this = Foo()
         self.assert_(isinstance(f.this, Foo))
 
     def test_subclass(self):
         class Foo(HasTraitlets):
             t = This()
         class Bar(Foo):
             pass
         f = Foo()
         b = Bar()
         f.t = b
         b.t = f
         self.assertEquals(f.t, b)
         self.assertEquals(b.t, f)
 
     def test_subclass_override(self):
         class Foo(HasTraitlets):
             t = This()
         class Bar(Foo):
             t = This()
         f = Foo()
         b = Bar()
         f.t = b
         self.assertEquals(f.t, b)
         self.assertRaises(TraitletError, setattr, b, 't', f)
 
 class TraitletTestBase(TestCase):
     """A best testing class for basic traitlet types."""
 
     def assign(self, value):
         self.obj.value = value
 
     def coerce(self, value):
         return value
 
     def test_good_values(self):
         if hasattr(self, '_good_values'):
             for value in self._good_values:
                 self.assign(value)
                 self.assertEquals(self.obj.value, self.coerce(value))
 
     def test_bad_values(self):
         if hasattr(self, '_bad_values'):
             for value in self._bad_values:
                 self.assertRaises(TraitletError, self.assign, value)
 
     def test_default_value(self):
         if hasattr(self, '_default_value'):
             self.assertEquals(self._default_value, self.obj.value)
 
 
 class AnyTraitlet(HasTraitlets):
 
     value = Any
 
 class AnyTraitTest(TraitletTestBase):
 
     obj = AnyTraitlet()
 
     _default_value = None
     _good_values   = [10.0, 'ten', u'ten', [10], {'ten': 10},(10,), None, 1j]
     _bad_values    = []
 
 
 class IntTraitlet(HasTraitlets):
 
     value = Int(99)
 
 class TestInt(TraitletTestBase):
 
     obj = IntTraitlet()
     _default_value = 99
     _good_values   = [10, -10]
     _bad_values    = ['ten', u'ten', [10], {'ten': 10},(10,), None, 1j, 10L,
                       -10L, 10.1, -10.1, '10L', '-10L', '10.1', '-10.1', u'10L',
                       u'-10L', u'10.1', u'-10.1',  '10', '-10', u'10', u'-10']
 
 
 class LongTraitlet(HasTraitlets):
 
     value = Long(99L)
 
 class TestLong(TraitletTestBase):
 
     obj = LongTraitlet()
 
     _default_value = 99L
     _good_values   = [10, -10, 10L, -10L]
     _bad_values    = ['ten', u'ten', [10], [10l], {'ten': 10},(10,),(10L,),
                       None, 1j, 10.1, -10.1, '10', '-10', '10L', '-10L', '10.1',
                       '-10.1', u'10', u'-10', u'10L', u'-10L', u'10.1',
                       u'-10.1']
 
 
 class FloatTraitlet(HasTraitlets):
 
     value = Float(99.0)
 
 class TestFloat(TraitletTestBase):
 
     obj = FloatTraitlet()
 
     _default_value = 99.0
     _good_values   = [10, -10, 10.1, -10.1]
     _bad_values    = [10L, -10L, 'ten', u'ten', [10], {'ten': 10},(10,), None,
                       1j, '10', '-10', '10L', '-10L', '10.1', '-10.1', u'10',
                       u'-10', u'10L', u'-10L', u'10.1', u'-10.1']
 
 
 class ComplexTraitlet(HasTraitlets):
 
     value = Complex(99.0-99.0j)
 
 class TestComplex(TraitletTestBase):
 
     obj = ComplexTraitlet()
 
     _default_value = 99.0-99.0j
     _good_values   = [10, -10, 10.1, -10.1, 10j, 10+10j, 10-10j, 
                       10.1j, 10.1+10.1j, 10.1-10.1j]
     _bad_values    = [10L, -10L, u'10L', u'-10L', 'ten', [10], {'ten': 10},(10,), None]
 
 
 class StringTraitlet(HasTraitlets):
 
     value = Str('string')
 
 class TestString(TraitletTestBase):
 
     obj = StringTraitlet()
 
     _default_value = 'string'
     _good_values   = ['10', '-10', '10L',
                       '-10L', '10.1', '-10.1', 'string']
     _bad_values    = [10, -10, 10L, -10L, 10.1, -10.1, 1j, [10],
                       ['ten'],{'ten': 10},(10,), None,  u'string']
 
 
 class UnicodeTraitlet(HasTraitlets):
 
     value = Unicode(u'unicode')
 
 class TestUnicode(TraitletTestBase):
 
     obj = UnicodeTraitlet()
 
     _default_value = u'unicode'
     _good_values   = ['10', '-10', '10L', '-10L', '10.1', 
                       '-10.1', '', u'', 'string', u'string', ]
     _bad_values    = [10, -10, 10L, -10L, 10.1, -10.1, 1j,
                       [10], ['ten'], [u'ten'], {'ten': 10},(10,), None]

IPython/utils/traitlets.py

@@ -1,858 +1,861 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 A lightweight Traits like module.
 
 This is designed to provide a lightweight, simple, pure Python version of
 many of the capabilities of enthought.traits.  This includes:
 
 * Validation
 * Type specification with defaults
 * Static and dynamic notification
 * Basic predefined types
 * An API that is similar to enthought.traits
 
 We don't support:
 
 * Delegation
 * Automatic GUI generation
 * A full set of trait types.  Most importantly, we don't provide container
   traitlets (list, dict, tuple) that can trigger notifications if their
   contents change.
 * API compatibility with enthought.traits
 
 There are also some important difference in our design:
 
 * enthought.traits does not validate default values.  We do.
 
 We choose to create this module because we need these capabilities, but
 we need them to be pure Python so they work in all Python implementations,
 including Jython and IronPython.
 
 Authors:
 
 * Brian Granger
 * Enthought, Inc.  Some of the code in this file comes from enthought.traits
   and is licensed under the BSD license.  Also, many of the ideas also come
   from enthought.traits even though our implementation is very different.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 
 import inspect
 import sys
 import types
 from types import InstanceType, ClassType, FunctionType
 
 ClassTypes = (ClassType, type)
 
 #-----------------------------------------------------------------------------
 # Basic classes
 #-----------------------------------------------------------------------------
 
 
 class NoDefaultSpecified ( object ): pass
 NoDefaultSpecified = NoDefaultSpecified()
 
 
 class Undefined ( object ): pass
 Undefined = Undefined()
 
 
 class TraitletError(Exception):
     pass
 
 
 #-----------------------------------------------------------------------------
 # Utilities
 #-----------------------------------------------------------------------------
 
 
 def class_of ( object ):
     """ Returns a string containing the class name of an object with the
     correct indefinite article ('a' or 'an') preceding it (e.g., 'an Image',
     'a PlotValue').
     """
     if isinstance( object, basestring ):
         return add_article( object )
 
     return add_article( object.__class__.__name__ )
 
 
 def add_article ( name ):
     """ Returns a string containing the correct indefinite article ('a' or 'an')
     prefixed to the specified string.
     """
     if name[:1].lower() in 'aeiou':
        return 'an ' + name
 
     return 'a ' + name
 
 
 def repr_type(obj):
     """ Return a string representation of a value and its type for readable
     error messages.
     """
     the_type = type(obj)
     if the_type is InstanceType:
         # Old-style class.
         the_type = obj.__class__
     msg = '%r %r' % (obj, the_type)
     return msg
 
 
 def parse_notifier_name(name):
     """Convert the name argument to a list of names.
     
     Examples
     --------
     
     >>> parse_notifier_name('a')
     ['a']
     >>> parse_notifier_name(['a','b'])
     ['a', 'b']
     >>> parse_notifier_name(None)
     ['anytraitlet']
     """
     if isinstance(name, str):
         return [name]
     elif name is None:
         return ['anytraitlet']
     elif isinstance(name, (list, tuple)):
         for n in name:
             assert isinstance(n, str), "names must be strings"
         return name
 
 
 class _SimpleTest:
     def __init__ ( self, value ): self.value = value
     def __call__ ( self, test  ):
         print test, self.value 
         return test == self.value
     def __repr__(self):
         return "<SimpleTest(%r)" % self.value
     def __str__(self):
         return self.__repr__()
 
 
 #-----------------------------------------------------------------------------
 # Base TraitletType for all traitlets
 #-----------------------------------------------------------------------------
 
 
 class TraitletType(object):
     """A base class for all traitlet descriptors.
 
     Notes
     -----
     Our implementation of traitlets is based on Python's descriptor
     prototol.  This class is the base class for all such descriptors.  The
     only magic we use is a custom metaclass for the main :class:`HasTraitlets`
     class that does the following:
 
     1. Sets the :attr:`name` attribute of every :class:`TraitletType`
        instance in the class dict to the name of the attribute.
     2. Sets the :attr:`this_class` attribute of every :class:`TraitletType`
        instance in the class dict to the *class* that declared the traitlet.
        This is used by the :class:`This` traitlet to allow subclasses to
        accept superclasses for :class:`This` values.
     """
     
 
     metadata = {}
     default_value = Undefined
     info_text = 'any value'
 
     def __init__(self, default_value=NoDefaultSpecified, **metadata):
         """Create a TraitletType.
         """
         if default_value is not NoDefaultSpecified:
             self.default_value = default_value
 
         if len(metadata) > 0:
             if len(self.metadata) > 0:
                 self._metadata = self.metadata.copy()
                 self._metadata.update(metadata)
             else:
                 self._metadata = metadata
         else:
             self._metadata = self.metadata
 
         self.init()
 
     def init(self):
         pass
 
     def get_default_value(self):
         """Create a new instance of the default value."""
         dv = self.default_value
         return dv
 
     def set_default_value(self, obj):
         dv = self.get_default_value()
         newdv = self._validate(obj, dv)
         obj._traitlet_values[self.name] = newdv
         
 
     def __get__(self, obj, cls=None):
         """Get the value of the traitlet by self.name for the instance.
 
         Default values are instantiated when :meth:`HasTraitlets.__new__`
         is called.  Thus by the time this method gets called either the 
         default value or a user defined value (they called :meth:`__set__`)
         is in the :class:`HasTraitlets` instance.
         """
         if obj is None:
             return self
         else:
             try:
                 value = obj._traitlet_values[self.name]
             except:
                 # HasTraitlets should call set_default_value to populate
                 # this.  So this should never be reached.
                 raise TraitletError('Unexpected error in TraitletType: '
                                     'default value not set properly')
             else:
                 return value
 
     def __set__(self, obj, value):
         new_value = self._validate(obj, value)
         old_value = self.__get__(obj)
         if old_value != new_value:
             obj._traitlet_values[self.name] = new_value
             obj._notify_traitlet(self.name, old_value, new_value)
 
     def _validate(self, obj, value):
         if hasattr(self, 'validate'):
             return self.validate(obj, value)
         elif hasattr(self, 'is_valid_for'):
             valid = self.is_valid_for(value)
             if valid:
                 return value
             else:
                 raise TraitletError('invalid value for type: %r' % value)
         elif hasattr(self, 'value_for'):
             return self.value_for(value)
         else:
             return value
 
     def info(self):
         return self.info_text
 
     def error(self, obj, value):
         if obj is not None:
             e = "The '%s' traitlet of %s instance must be %s, but a value of %s was specified." \
                 % (self.name, class_of(obj),
                    self.info(), repr_type(value))
         else:
             e = "The '%s' traitlet must be %s, but a value of %r was specified." \
                 % (self.name, self.info(), repr_type(value))            
         raise TraitletError(e)
 
     def get_metadata(self, key):
         return getattr(self, '_metadata', {}).get(key, None)
 
     def set_metadata(self, key, value):
         getattr(self, '_metadata', {})[key] = value
 
 
 #-----------------------------------------------------------------------------
 # The HasTraitlets implementation
 #-----------------------------------------------------------------------------
 
 
 class MetaHasTraitlets(type):
     """A metaclass for HasTraitlets.
     
     This metaclass makes sure that any TraitletType class attributes are
     instantiated and sets their name attribute.
     """
     
     def __new__(mcls, name, bases, classdict):
         """Create the HasTraitlets class.
         
         This instantiates all TraitletTypes in the class dict and sets their
         :attr:`name` attribute.
         """
         # print "========================="
         # print "MetaHasTraitlets.__new__"
         # print "mcls, ", mcls
         # print "name, ", name
         # print "bases, ", bases
         # print "classdict, ", classdict
         for k,v in classdict.iteritems():
             if isinstance(v, TraitletType):
                 v.name = k
             elif inspect.isclass(v):
                 if issubclass(v, TraitletType):
                     vinst = v()
                     vinst.name = k
                     classdict[k] = vinst
         return super(MetaHasTraitlets, mcls).__new__(mcls, name, bases, classdict)
 
     def __init__(cls, name, bases, classdict):
         """Finish initializing the HasTraitlets class.
         
         This sets the :attr:`this_class` attribute of each TraitletType in the
         class dict to the newly created class ``cls``.
         """
         # print "========================="
         # print "MetaHasTraitlets.__init__"
         # print "cls, ", cls
         # print "name, ", name
         # print "bases, ", bases
         # print "classdict, ", classdict
         for k, v in classdict.iteritems():
             if isinstance(v, TraitletType):
                 v.this_class = cls
         super(MetaHasTraitlets, cls).__init__(name, bases, classdict)
 
 class HasTraitlets(object):
 
     __metaclass__ = MetaHasTraitlets
 
     def __new__(cls, *args, **kw):
         inst = super(HasTraitlets, cls).__new__(cls, *args, **kw)
         inst._traitlet_values = {}
         inst._traitlet_notifiers = {}
         # Here we tell all the TraitletType instances to set their default
         # values on the instance. 
         for key in dir(cls):
             value = getattr(cls, key)
             if isinstance(value, TraitletType):
                 value.set_default_value(inst)
         return inst
 
     # def __init__(self):
     #     self._traitlet_values = {}
     #     self._traitlet_notifiers = {}
 
     def _notify_traitlet(self, name, old_value, new_value):
 
         # First dynamic ones
         callables = self._traitlet_notifiers.get(name,[])
         more_callables = self._traitlet_notifiers.get('anytraitlet',[])
         callables.extend(more_callables)
 
         # Now static ones
         try:
             cb = getattr(self, '_%s_changed' % name)
         except:
             pass
         else:
             callables.append(cb)
 
         # Call them all now
         for c in callables:
             # Traits catches and logs errors here.  I allow them to raise
             if callable(c):
                 argspec = inspect.getargspec(c)
                 nargs = len(argspec[0])
                 # Bound methods have an additional 'self' argument
                 # I don't know how to treat unbound methods, but they
                 # can't really be used for callbacks.
                 if isinstance(c, types.MethodType):
                     offset = -1
                 else:
                     offset = 0
                 if nargs + offset == 0:
                     c()
                 elif nargs + offset == 1:
                     c(name)
                 elif nargs + offset == 2:
                     c(name, new_value)
                 elif nargs + offset == 3:
                     c(name, old_value, new_value)
                 else:
                     raise TraitletError('a traitlet changed callback '
                                         'must have 0-3 arguments.')
             else:
                 raise TraitletError('a traitlet changed callback '
                                     'must be callable.')
                 
 
     def _add_notifiers(self, handler, name):
         if not self._traitlet_notifiers.has_key(name):
             nlist = []
             self._traitlet_notifiers[name] = nlist
         else:
             nlist = self._traitlet_notifiers[name]
         if handler not in nlist:
             nlist.append(handler)
 
     def _remove_notifiers(self, handler, name):
         if self._traitlet_notifiers.has_key(name):
             nlist = self._traitlet_notifiers[name]
             try:
                 index = nlist.index(handler)
             except ValueError:
                 pass
             else:
                 del nlist[index]
 
     def on_traitlet_change(self, handler, name=None, remove=False):
         """Setup a handler to be called when a traitlet changes.
 
         This is used to setup dynamic notifications of traitlet changes.
         
         Static handlers can be created by creating methods on a HasTraitlets
         subclass with the naming convention '_[traitletname]_changed'.  Thus,
         to create static handler for the traitlet 'a', create the method
         _a_changed(self, name, old, new) (fewer arguments can be used, see
         below).
         
         Parameters
         ----------
             handler : callable
                 A callable that is called when a traitlet changes.  Its 
                 signature can be handler(), handler(name), handler(name, new)
                 or handler(name, old, new).
             name : list, str, None
                 If None, the handler will apply to all traitlets.  If a list
                 of str, handler will apply to all names in the list.  If a
                 str, the handler will apply just to that name.
             remove : bool
                 If False (the default), then install the handler.  If True
                 then unintall it.
         """
         if remove:
             names = parse_notifier_name(name)
             for n in names:
                 self._remove_notifiers(handler, n)
         else:
             names = parse_notifier_name(name)
             for n in names:
                 self._add_notifiers(handler, n)
 
     def traitlet_names(self, **metadata):
         """Get a list of all the names of this classes traitlets."""
         return self.traitlets(**metadata).keys()
 
-    def traitlets(self, **metadata):
+    def traitlets(self, *args, **metadata):
         """Get a list of all the traitlets of this class.
 
         The TraitletTypes returned don't know anything about the values
         that the various HasTraitlet's instances are holding.
         """
         traitlets = dict([memb for memb in inspect.getmembers(self.__class__) if \
                      isinstance(memb[1], TraitletType)])
-        if len(metadata) == 0:
+        if len(metadata) == 0 and len(args) == 0:
             return traitlets
 
+        for meta_name in args:
+            metadata[meta_name] = lambda _: True
+
         for meta_name, meta_eval in metadata.items():
             if type(meta_eval) is not FunctionType:
                 metadata[meta_name] = _SimpleTest(meta_eval)
 
         result = {}
         for name, traitlet in traitlets.items():
             for meta_name, meta_eval in metadata.items():
                 if not meta_eval(traitlet.get_metadata(meta_name)):
                     break
             else:
                 result[name] = traitlet
 
         return result
 
     def traitlet_metadata(self, traitletname, key):
         """Get metadata values for traitlet by key."""
         try:
             traitlet = getattr(self.__class__, traitletname)
         except AttributeError:
             raise TraitletError("Class %s does not have a traitlet named %s" %
                                 (self.__class__.__name__, traitletname))
         else:
             return traitlet.get_metadata(key)
 
 #-----------------------------------------------------------------------------
 # Actual TraitletTypes implementations/subclasses
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # TraitletTypes subclasses for handling classes and instances of classes
 #-----------------------------------------------------------------------------
 
 
 class ClassBasedTraitletType(TraitletType):
     """A traitlet with error reporting for Type, Instance and This."""
 
     def error(self, obj, value):
         kind = type(value)
         if kind is InstanceType:
             msg = 'class %s' % value.__class__.__name__
         else:
             msg = '%s (i.e. %s)' % ( str( kind )[1:-1], repr( value ) )
 
         super(ClassBasedTraitletType, self).error(obj, msg)
 
 
 class Type(ClassBasedTraitletType):
     """A traitlet whose value must be a subclass of a specified class."""
 
     def __init__ (self, default_value=None, klass=None, allow_none=True, **metadata ):
         """Construct a Type traitlet
 
         A Type traitlet specifies that its values must be subclasses of
         a particular class.
 
         Parameters
         ----------
         default_value : class
             The default value must be a subclass of klass.
         klass : class, str, None
             Values of this traitlet must be a subclass of klass.  The klass
             may be specified in a string like: 'foo.bar.MyClass'.
         allow_none : boolean
             Indicates whether None is allowed as an assignable value. Even if
             ``False``, the default value may be ``None``.
         """
         if default_value is None:
             if klass is None:
                 klass = object
         elif klass is None:
             klass = default_value
 
         if not inspect.isclass(klass):
             raise TraitletError("A Type traitlet must specify a class.")
 
         self.klass       = klass
         self._allow_none = allow_none
 
         super(Type, self).__init__(default_value, **metadata)
 
     def validate(self, obj, value):
         """Validates that the value is a valid object instance."""
         try:
             if issubclass(value, self.klass):
                 return value
         except:
             if (value is None) and (self._allow_none):
                 return value
 
         self.error(obj, value)
 
     def info(self):
         """ Returns a description of the trait."""
         klass = self.klass.__name__
         result = 'a subclass of ' + klass
         if self._allow_none:
             return result + ' or None'
         return result
 
 
 class DefaultValueGenerator(object):
     """A class for generating new default value instances."""
 
     def __init__(self, klass, *args, **kw):
         self.klass = klass
         self.args = args
         self.kw = kw
 
     def generate(self):
         return self.klass(*self.args, **self.kw)
 
 
 class Instance(ClassBasedTraitletType):
     """A trait whose value must be an instance of a specified class.
     
     The value can also be an instance of a subclass of the specified class.
     """
 
     def __init__(self, klass=None, args=None, kw=None, 
                  allow_none=True, **metadata ):
         """Construct an Instance traitlet.
 
         This traitlet allows values that are instances of a particular
         class or its sublclasses.  Our implementation is quite different
         from that of enthough.traits as we don't allow instances to be used
         for klass and we handle the ``args`` and ``kw`` arguments differently.
 
         Parameters
         ----------
         klass : class
             The class that forms the basis for the traitlet.  Instances
             and strings are not allowed.
         args : tuple
             Positional arguments for generating the default value.
         kw : dict
             Keyword arguments for generating the default value.
         allow_none : bool
             Indicates whether None is allowed as a value.
 
         Default Value
         -------------
         If both ``args`` and ``kw`` are None, then the default value is None.
         If ``args`` is a tuple and ``kw`` is a dict, then the default is
         created as ``klass(*args, **kw)``.  If either ``args`` or ``kw`` is 
         not (but not both), None is replace by ``()`` or ``{}``.
         """
 
         self._allow_none = allow_none
 
         if (klass is None) or (not inspect.isclass(klass)):
             raise TraitletError('The klass argument must be a class'
                                 ' you gave: %r' % klass)
         self.klass = klass
         
         # self.klass is a class, so handle default_value
         if args is None and kw is None:
             default_value = None
         else:
             if args is None:
                 # kw is not None
                 args = ()
             elif kw is None:
                 # args is not None
                 kw = {}
         
             if not isinstance(kw, dict):
                 raise TraitletError("The 'kw' argument must be a dict or None.")
             if not isinstance(args, tuple):
                 raise TraitletError("The 'args' argument must be a tuple or None.")
             
             default_value = DefaultValueGenerator(self.klass, *args, **kw)
 
         super(Instance, self).__init__(default_value, **metadata)
 
     def validate(self, obj, value):
         if value is None:
             if self._allow_none:
                 return value
             self.error(obj, value)
 
         if isinstance(value, self.klass):
             return value
         else:
             self.error(obj, value)
 
     def info(self):
         klass = self.klass.__name__
         result = class_of(klass)
         if self._allow_none:
             return result + ' or None'
 
         return result
 
     def get_default_value(self):
         """Instantiate a default value instance.
         
         This is called when the containing HasTraitlets classes'
         :meth:`__new__` method is called to ensure that a unique instance
         is created for each HasTraitlets instance.
         """
         dv  = self.default_value
         if isinstance(dv, DefaultValueGenerator):
             return dv.generate()
         else:
             return dv
 
 
 class This(ClassBasedTraitletType):
     """A traitlet for instances of the class containing this trait.
 
     Because how how and when class bodies are executed, the ``This``
     traitlet can only have a default value of None.  This, and because we 
     always validate default values, ``allow_none`` is *always* true.
     """
 
     info_text = 'an instance of the same type as the receiver or None'
 
     def __init__(self, **metadata):
         super(This, self).__init__(None, **metadata)
 
     def validate(self, obj, value):
         # What if value is a superclass of obj.__class__?  This is
         # complicated if it was the superclass that defined the This
         # traitlet.
         if isinstance(value, self.this_class) or (value is None):
             return value
         else:
             self.error(obj, value)
 
 
 #-----------------------------------------------------------------------------
 # Basic TraitletTypes implementations/subclasses
 #-----------------------------------------------------------------------------
 
 
 class Any(TraitletType):
     default_value = None
     info_text = 'any value'
 
 
 class Int(TraitletType):
     """A integer traitlet."""
 
     evaluate = int
     default_value = 0
     info_text = 'an integer'
 
     def validate(self, obj, value):
         if isinstance(value, int):
             return value
         self.error(obj, value)
 
 class CInt(Int):
     """A casting version of the int traitlet."""
 
     def validate(self, obj, value):
         try:
             return int(value)
         except:
             self.error(obj, value)
 
 
 class Long(TraitletType):
     """A long integer traitlet."""
 
     evaluate = long
     default_value = 0L
     info_text = 'a long'
 
     def validate(self, obj, value):
         if isinstance(value, long):
             return value
         if isinstance(value, int):
             return long(value)
         self.error(obj, value)
 
 
 class CLong(Long):
     """A casting version of the long integer traitlet."""
 
     def validate(self, obj, value):
         try:
             return long(value)
         except:
             self.error(obj, value)
 
 
 class Float(TraitletType):
     """A float traitlet."""
 
     evaluate = float
     default_value = 0.0
     info_text = 'a float'
 
     def validate(self, obj, value):
         if isinstance(value, float):
             return value
         if isinstance(value, int):
             return float(value)
         self.error(obj, value)
 
 
 class CFloat(Float):
     """A casting version of the float traitlet."""
 
     def validate(self, obj, value):
         try:
             return float(value)
         except:
             self.error(obj, value)
 
 class Complex(TraitletType):
     """A traitlet for complex numbers."""
 
     evaluate = complex
     default_value = 0.0 + 0.0j
     info_text = 'a complex number'
 
     def validate(self, obj, value):
         if isinstance(value, complex):
             return value
         if isinstance(value, (float, int)):
             return complex(value)
         self.error(obj, value)
 
 
 class CComplex(Complex):
     """A casting version of the complex number traitlet."""
 
     def validate (self, obj, value):
         try:
             return complex(value)
         except:
             self.error(obj, value)
 
 
 class Str(TraitletType):
     """A traitlet for strings."""
 
     evaluate = lambda x: x
     default_value = ''
     info_text = 'a string'
 
     def validate(self, obj, value):
         if isinstance(value, str):
             return value
         self.error(obj, value)
 
 
 class CStr(Str):
     """A casting version of the string traitlet."""
 
     def validate(self, obj, value):
         try:
             return str(value)
         except:
             try:
                 return unicode(value)
             except:
                 self.error(obj, value)
 
 
 class Unicode(TraitletType):
     """A traitlet for unicode strings."""
 
     evaluate = unicode
     default_value = u''
     info_text = 'a unicode string'
 
     def validate(self, obj, value):
         if isinstance(value, unicode):
             return value
         if isinstance(value, str):
             return unicode(value)
         self.error(obj, value)
 
 
 class CUnicode(Unicode):
     """A casting version of the unicode traitlet."""
 
     def validate(self, obj, value):
         try:
             return unicode(value)
         except:
             self.error(obj, value)
 
 
 class Bool(TraitletType):
     """A boolean (True, False) traitlet."""
     evaluate = bool
     default_value = False
     info_text = 'a boolean'
 
     def validate(self, obj, value):
         if isinstance(value, bool):
             return value
         self.error(obj, value)
 
 
 class CBool(Bool):
     """A casting version of the boolean traitlet."""
 
     def validate(self, obj, value):
         try:
             return bool(value)
         except:
             self.error(obj, value)
  No newline at end of file