Remove a few usage of PromptManager in example

Make PromptClass Configurable.

IPython/core/interactiveshell.py

@@ -1,3233 +1,3227 b''
 # -*- coding: utf-8 -*-
 """Main IPython class."""
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2001 Janko Hauser <[e-mail]>
 #  Copyright (C) 2001-2007 Fernando Perez. <[e-mail]>
 #  Copyright (C) 2008-2011  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.
 #-----------------------------------------------------------------------------
 
 from __future__ import absolute_import, print_function
 
 import __future__
 import abc
 import ast
 import atexit
 import functools
 import os
 import re
 import runpy
 import sys
 import tempfile
 import traceback
 import types
 import subprocess
 import warnings
 from io import open as io_open
 
 from pickleshare import PickleShareDB
 
 from traitlets.config.configurable import SingletonConfigurable
 from IPython.core import oinspect
 from IPython.core import magic
 from IPython.core import page
 from IPython.core import prefilter
 from IPython.core import shadowns
 from IPython.core import ultratb
 from IPython.core.alias import Alias, AliasManager
 from IPython.core.autocall import ExitAutocall
 from IPython.core.builtin_trap import BuiltinTrap
 from IPython.core.events import EventManager, available_events
 from IPython.core.compilerop import CachingCompiler, check_linecache_ipython
 from IPython.core.debugger import Pdb
 from IPython.core.display_trap import DisplayTrap
 from IPython.core.displayhook import DisplayHook
 from IPython.core.displaypub import DisplayPublisher
 from IPython.core.error import InputRejected, UsageError
 from IPython.core.extensions import ExtensionManager
 from IPython.core.formatters import DisplayFormatter
 from IPython.core.history import HistoryManager
 from IPython.core.inputsplitter import ESC_MAGIC, ESC_MAGIC2
 from IPython.core.logger import Logger
 from IPython.core.macro import Macro
 from IPython.core.payload import PayloadManager
 from IPython.core.prefilter import PrefilterManager
 from IPython.core.profiledir import ProfileDir
 from IPython.core.usage import default_banner
 from IPython.testing.skipdoctest import skip_doctest_py2, skip_doctest
 from IPython.utils import PyColorize
 from IPython.utils import io
 from IPython.utils import py3compat
 from IPython.utils import openpy
 from IPython.utils.contexts import NoOpContext
 from IPython.utils.decorators import undoc
 from IPython.utils.io import ask_yes_no
 from IPython.utils.ipstruct import Struct
 from IPython.paths import get_ipython_dir
 from IPython.utils.path import get_home_dir, get_py_filename, ensure_dir_exists
 from IPython.utils.process import system, getoutput
 from IPython.utils.py3compat import (builtin_mod, unicode_type, string_types,
                                      with_metaclass, iteritems)
 from IPython.utils.strdispatch import StrDispatch
 from IPython.utils.syspathcontext import prepended_to_syspath
 from IPython.utils.text import (format_screen, LSString, SList,
                                 DollarFormatter)
 from traitlets import (
     Integer, Bool, CaselessStrEnum, Enum, List, Dict, Unicode, Instance, Type,
     observe, default,
 )
 from warnings import warn
 from logging import error
 import IPython.core.hooks
 
 #-----------------------------------------------------------------------------
 # Globals
 #-----------------------------------------------------------------------------
 
 # compiled regexps for autoindent management
 dedent_re = re.compile(r'^\s+raise|^\s+return|^\s+pass')
 
 #-----------------------------------------------------------------------------
 # Utilities
 #-----------------------------------------------------------------------------
 
 @undoc
 def softspace(file, newvalue):
     """Copied from code.py, to remove the dependency"""
 
     oldvalue = 0
     try:
         oldvalue = file.softspace
     except AttributeError:
         pass
     try:
         file.softspace = newvalue
     except (AttributeError, TypeError):
         # "attribute-less object" or "read-only attributes"
         pass
     return oldvalue
 
 @undoc
 def no_op(*a, **kw): pass
 
 
 class SpaceInInput(Exception): pass
 
 
 def get_default_colors():
     if sys.platform=='darwin':
         return "LightBG"
     elif os.name=='nt':
         return 'Linux'
     else:
         return 'Linux'
 
 
 class SeparateUnicode(Unicode):
     r"""A Unicode subclass to validate separate_in, separate_out, etc.
 
     This is a Unicode based trait that converts '0'->'' and ``'\\n'->'\n'``.
     """
 
     def validate(self, obj, value):
         if value == '0': value = ''
         value = value.replace('\\n','\n')
         return super(SeparateUnicode, self).validate(obj, value)
 
 
 @undoc
 class DummyMod(object):
     """A dummy module used for IPython's interactive module when
     a namespace must be assigned to the module's __dict__."""
     pass
 
 
 class ExecutionResult(object):
     """The result of a call to :meth:`InteractiveShell.run_cell`
 
     Stores information about what took place.
     """
     execution_count = None
     error_before_exec = None
     error_in_exec = None
     result = None
 
     @property
     def success(self):
         return (self.error_before_exec is None) and (self.error_in_exec is None)
 
     def raise_error(self):
         """Reraises error if `success` is `False`, otherwise does nothing"""
         if self.error_before_exec is not None:
             raise self.error_before_exec
         if self.error_in_exec is not None:
             raise self.error_in_exec
 
 
 class InteractiveShell(SingletonConfigurable):
     """An enhanced, interactive shell for Python."""
 
     _instance = None
     
     ast_transformers = List([], help=
         """
         A list of ast.NodeTransformer subclass instances, which will be applied
         to user input before code is run.
         """
     ).tag(config=True)
 
     autocall = Enum((0,1,2), default_value=0, help=
         """
         Make IPython automatically call any callable object even if you didn't
         type explicit parentheses. For example, 'str 43' becomes 'str(43)'
         automatically. The value can be '0' to disable the feature, '1' for
         'smart' autocall, where it is not applied if there are no more
         arguments on the line, and '2' for 'full' autocall, where all callable
         objects are automatically called (even if no arguments are present).
         """
     ).tag(config=True)
     # TODO: remove all autoindent logic and put into frontends.
     # We can't do this yet because even runlines uses the autoindent.
     autoindent = Bool(True, help=
         """
         Autoindent IPython code entered interactively.
         """
     ).tag(config=True)
     automagic = Bool(True, help=
         """
         Enable magic commands to be called without the leading %.
         """
     ).tag(config=True)
     
     banner1 = Unicode(default_banner,
         help="""The part of the banner to be printed before the profile"""
     ).tag(config=True)
     banner2 = Unicode('',
         help="""The part of the banner to be printed after the profile"""
     ).tag(config=True)
 
     cache_size = Integer(1000, help=
         """
         Set the size of the output cache.  The default is 1000, you can
         change it permanently in your config file.  Setting it to 0 completely
         disables the caching system, and the minimum value accepted is 20 (if
         you provide a value less than 20, it is reset to 0 and a warning is
         issued).  This limit is defined because otherwise you'll spend more
         time re-flushing a too small cache than working
         """
     ).tag(config=True)
     color_info = Bool(True, help=
         """
         Use colors for displaying information about objects. Because this
         information is passed through a pager (like 'less'), and some pagers
         get confused with color codes, this capability can be turned off.
         """
     ).tag(config=True)
     colors = CaselessStrEnum(('NoColor','LightBG','Linux'),
                              default_value=get_default_colors(),
         help="Set the color scheme (NoColor, Linux, or LightBG)."
     ).tag(config=True)
     colors_force = Bool(False, help=
         """
         Force use of ANSI color codes, regardless of OS and readline
         availability.
         """
         # FIXME: This is essentially a hack to allow ZMQShell to show colors
         # without readline on Win32. When the ZMQ formatting system is
         # refactored, this should be removed.
     )
     debug = Bool(False).tag(config=True)
     deep_reload = Bool(False, help=
         """
         **Deprecated**
 
         Will be removed in IPython 6.0
 
         Enable deep (recursive) reloading by default. IPython can use the
         deep_reload module which reloads changes in modules recursively (it
         replaces the reload() function, so you don't need to change anything to
         use it). `deep_reload` forces a full reload of modules whose code may
         have changed, which the default reload() function does not.  When
         deep_reload is off, IPython will use the normal reload(), but
         deep_reload will still be available as dreload().
         """
     ).tag(config=True)
     disable_failing_post_execute = Bool(False,
         help="Don't call post-execute functions that have failed in the past."
     ).tag(config=True)
     display_formatter = Instance(DisplayFormatter, allow_none=True)
     displayhook_class = Type(DisplayHook)
     display_pub_class = Type(DisplayPublisher)
     data_pub_class = None
 
     exit_now = Bool(False)
     exiter = Instance(ExitAutocall)
     @default('exiter')
     def _exiter_default(self):
         return ExitAutocall(self)
     # Monotonically increasing execution counter
     execution_count = Integer(1)
     filename = Unicode("<ipython console>")
     ipython_dir= Unicode('').tag(config=True) # Set to get_ipython_dir() in __init__
 
     # Input splitter, to transform input line by line and detect when a block
     # is ready to be executed.
     input_splitter = Instance('IPython.core.inputsplitter.IPythonInputSplitter',
                               (), {'line_input_checker': True})
     
     # This InputSplitter instance is used to transform completed cells before
     # running them. It allows cell magics to contain blank lines.
     input_transformer_manager = Instance('IPython.core.inputsplitter.IPythonInputSplitter',
                                          (), {'line_input_checker': False})
     
     logstart = Bool(False, help=
         """
         Start logging to the default log file in overwrite mode.
         Use `logappend` to specify a log file to **append** logs to.
         """
     ).tag(config=True)
     logfile = Unicode('', help=
         """
         The name of the logfile to use.
         """
     ).tag(config=True)
     logappend = Unicode('', help=
         """
         Start logging to the given file in append mode.
         Use `logfile` to specify a log file to **overwrite** logs to.
         """
     ).tag(config=True)
     object_info_string_level = Enum((0,1,2), default_value=0,
     ).tag(config=True)
     pdb = Bool(False, help=
         """
         Automatically call the pdb debugger after every exception.
         """
     ).tag(config=True)
     multiline_history = Bool(sys.platform != 'win32',
         help="Save multi-line entries as one entry in readline history"
     ).tag(config=True)
     display_page = Bool(False,
         help="""If True, anything that would be passed to the pager
         will be displayed as regular output instead."""
     ).tag(config=True)
 
     # deprecated prompt traits:
     
     prompt_in1 = Unicode('In [\\#]: ',
-        help="Deprecated, will be removed in IPython 5.0, use PromptManager.in_template"
+        help="Deprecated since IPython 4.0 and ignored since 5.0, set IPython.terminal.ptshell.TerminalInteractiveShell.prompts object directly."
     ).tag(config=True)
     prompt_in2 = Unicode('   .\\D.: ',
-        help="Deprecated, will be removed in IPython 5.0, use PromptManager.in2_template"
+        help="Deprecated since IPython 4.0 and ignored since 5.0, set IPython.terminal.ptshell.TerminalInteractiveShell.prompts object directly."
     ).tag(config=True)
     prompt_out = Unicode('Out[\\#]: ',
-        help="Deprecated, will be removed in IPython 5.0, use PromptManager.out_template"
+        help="Deprecated since IPython 4.0 and ignored since 5.0, set IPython.terminal.ptshell.TerminalInteractiveShell.prompts object directly."
     ).tag(config=True)
     prompts_pad_left = Bool(True,
-        help="Deprecated, will be removed in IPython 5.0, use PromptManager.justify"
+        help="Deprecated since IPython 4.0 and ignored since 5.0, set IPython.terminal.ptshell.TerminalInteractiveShell.prompts object directly."
     ).tag(config=True)
     
     @observe('prompt_in1', 'prompt_in2', 'prompt_out', 'prompt_pad_left')
     def _prompt_trait_changed(self, change):
-        table = {
-            'prompt_in1' : 'in_template',
-            'prompt_in2' : 'in2_template',
-            'prompt_out' : 'out_template',
-            'prompts_pad_left' : 'justify',
-        }
         name = change['name']
-        warn("InteractiveShell.{name} is deprecated, use PromptManager.{newname}".format(
-                name=name, newname=table[name])
+        warn("InteractiveShell.{name} is deprecated since IPython 4.0 and ignored since 5.0, set IPython.terminal.ptshell.TerminalInteractiveShell.prompts object directly.".format(
+                name=name)
         )
         # protect against weird cases where self.config may not exist:
-        if self.config is not None:
-            # propagate to corresponding PromptManager trait
-            setattr(self.config.PromptManager, table[name], change['new'])
     
     show_rewritten_input = Bool(True,
         help="Show rewritten input, e.g. for autocall."
     ).tag(config=True)
     
     quiet = Bool(False).tag(config=True)
 
     history_length = Integer(10000,
         help='Total length of command history'
     ).tag(config=True)
 
     history_load_length = Integer(1000, help=
         """
         The number of saved history entries to be loaded
         into the readline buffer at startup.
         """
     ).tag(config=True)
 
     # The readline stuff will eventually be moved to the terminal subclass
     # but for now, we can't do that as readline is welded in everywhere.
     readline_use = Bool(True).tag(config=True)
     readline_remove_delims = Unicode('-/~').tag(config=True)
     readline_delims = Unicode() # set by init_readline()
     # don't use \M- bindings by default, because they
     # conflict with 8-bit encodings. See gh-58,gh-88
     readline_parse_and_bind = List([
             'tab: complete',
             '"\C-l": clear-screen',
             'set show-all-if-ambiguous on',
             '"\C-o": tab-insert',
             '"\C-r": reverse-search-history',
             '"\C-s": forward-search-history',
             '"\C-p": history-search-backward',
             '"\C-n": history-search-forward',
             '"\e[A": history-search-backward',
             '"\e[B": history-search-forward',
             '"\C-k": kill-line',
             '"\C-u": unix-line-discard',
         ]).tag(config=True)
     
     _custom_readline_config = False
     
     @observe('readline_parse_and_bind')
     def _readline_parse_and_bind_changed(self, change):
         # notice that readline config is customized
         # indicates that it should have higher priority than inputrc
         self._custom_readline_config = True
     
     ast_node_interactivity = Enum(['all', 'last', 'last_expr', 'none'],
                                   default_value='last_expr',
                                   help="""
         'all', 'last', 'last_expr' or 'none', specifying which nodes should be
         run interactively (displaying output from expressions)."""
     ).tag(config=True)
 
     # TODO: this part of prompt management should be moved to the frontends.
     # Use custom TraitTypes that convert '0'->'' and '\\n'->'\n'
     separate_in = SeparateUnicode('\n').tag(config=True)
     separate_out = SeparateUnicode('').tag(config=True)
     separate_out2 = SeparateUnicode('').tag(config=True)
     wildcards_case_sensitive = Bool(True).tag(config=True)
     xmode = CaselessStrEnum(('Context','Plain', 'Verbose'),
                             default_value='Context').tag(config=True)
 
     # Subcomponents of InteractiveShell
     alias_manager = Instance('IPython.core.alias.AliasManager', allow_none=True)
     prefilter_manager = Instance('IPython.core.prefilter.PrefilterManager', allow_none=True)
     builtin_trap = Instance('IPython.core.builtin_trap.BuiltinTrap', allow_none=True)
     display_trap = Instance('IPython.core.display_trap.DisplayTrap', allow_none=True)
     extension_manager = Instance('IPython.core.extensions.ExtensionManager', allow_none=True)
     payload_manager = Instance('IPython.core.payload.PayloadManager', allow_none=True)
     history_manager = Instance('IPython.core.history.HistoryAccessorBase', allow_none=True)
     magics_manager = Instance('IPython.core.magic.MagicsManager', allow_none=True)
 
     profile_dir = Instance('IPython.core.application.ProfileDir', allow_none=True)
     @property
     def profile(self):
         if self.profile_dir is not None:
             name = os.path.basename(self.profile_dir.location)
             return name.replace('profile_','')
 
 
     # Private interface
     _post_execute = Dict()
 
     # Tracks any GUI loop loaded for pylab
     pylab_gui_select = None
 
     def __init__(self, ipython_dir=None, profile_dir=None,
                  user_module=None, user_ns=None,
                  custom_exceptions=((), None), **kwargs):
 
         # This is where traits with a config_key argument are updated
         # from the values on config.
         super(InteractiveShell, self).__init__(**kwargs)
+        if 'PromptManager' in self.config:
+            warn('As of IPython 5.0 `PromptManager` config will have no effect'
+                 ' and has been replaced by TerminalInteractiveShell.prompts_class')
         self.configurables = [self]
 
         # These are relatively independent and stateless
         self.init_ipython_dir(ipython_dir)
         self.init_profile_dir(profile_dir)
         self.init_instance_attrs()
         self.init_environment()
         
         # Check if we're in a virtualenv, and set up sys.path.
         self.init_virtualenv()
 
         # Create namespaces (user_ns, user_global_ns, etc.)
         self.init_create_namespaces(user_module, user_ns)
         # This has to be done after init_create_namespaces because it uses
         # something in self.user_ns, but before init_sys_modules, which
         # is the first thing to modify sys.
         # TODO: When we override sys.stdout and sys.stderr before this class
         # is created, we are saving the overridden ones here. Not sure if this
         # is what we want to do.
         self.save_sys_module_state()
         self.init_sys_modules()
 
         # While we're trying to have each part of the code directly access what
         # it needs without keeping redundant references to objects, we have too
         # much legacy code that expects ip.db to exist.
         self.db = PickleShareDB(os.path.join(self.profile_dir.location, 'db'))
 
         self.init_history()
         self.init_encoding()
         self.init_prefilter()
 
         self.init_syntax_highlighting()
         self.init_hooks()
         self.init_events()
         self.init_pushd_popd_magic()
         # self.init_traceback_handlers use to be here, but we moved it below
         # because it and init_io have to come after init_readline.
         self.init_user_ns()
         self.init_logger()
         self.init_builtins()
 
         # The following was in post_config_initialization
         self.init_inspector()
         # init_readline() must come before init_io(), because init_io uses
         # readline related things.
         self.init_readline()
         # We save this here in case user code replaces raw_input, but it needs
         # to be after init_readline(), because PyPy's readline works by replacing
         # raw_input.
         if py3compat.PY3:
             self.raw_input_original = input
         else:
             self.raw_input_original = raw_input
         # init_completer must come after init_readline, because it needs to
         # know whether readline is present or not system-wide to configure the
         # completers, since the completion machinery can now operate
         # independently of readline (e.g. over the network)
         self.init_completer()
         # TODO: init_io() needs to happen before init_traceback handlers
         # because the traceback handlers hardcode the stdout/stderr streams.
         # This logic in in debugger.Pdb and should eventually be changed.
         self.init_io()
         self.init_traceback_handlers(custom_exceptions)
         self.init_prompts()
         self.init_display_formatter()
         self.init_display_pub()
         self.init_data_pub()
         self.init_displayhook()
         self.init_magics()
         self.init_alias()
         self.init_logstart()
         self.init_pdb()
         self.init_extension_manager()
         self.init_payload()
         self.init_deprecation_warnings()
         self.hooks.late_startup_hook()
         self.events.trigger('shell_initialized', self)
         atexit.register(self.atexit_operations)
 
     def get_ipython(self):
         """Return the currently running IPython instance."""
         return self
 
     #-------------------------------------------------------------------------
     # Trait changed handlers
     #-------------------------------------------------------------------------
     @observe('ipython_dir')
     def _ipython_dir_changed(self, change):
         ensure_dir_exists(change['new'])
 
     def set_autoindent(self,value=None):
         """Set the autoindent flag.
 
         If called with no arguments, it acts as a toggle."""
         if value is None:
             self.autoindent = not self.autoindent
         else:
             self.autoindent = value
 
     #-------------------------------------------------------------------------
     # init_* methods called by __init__
     #-------------------------------------------------------------------------
 
     def init_ipython_dir(self, ipython_dir):
         if ipython_dir is not None:
             self.ipython_dir = ipython_dir
             return
 
         self.ipython_dir = get_ipython_dir()
 
     def init_profile_dir(self, profile_dir):
         if profile_dir is not None:
             self.profile_dir = profile_dir
             return
         self.profile_dir =\
             ProfileDir.create_profile_dir_by_name(self.ipython_dir, 'default')
 
     def init_instance_attrs(self):
         self.more = False
 
         # command compiler
         self.compile = CachingCompiler()
 
         # Make an empty namespace, which extension writers can rely on both
         # existing and NEVER being used by ipython itself.  This gives them a
         # convenient location for storing additional information and state
         # their extensions may require, without fear of collisions with other
         # ipython names that may develop later.
         self.meta = Struct()
 
         # Temporary files used for various purposes.  Deleted at exit.
         self.tempfiles = []
         self.tempdirs = []
 
         # Keep track of readline usage (later set by init_readline)
         self.has_readline = False
 
         # keep track of where we started running (mainly for crash post-mortem)
         # This is not being used anywhere currently.
         self.starting_dir = py3compat.getcwd()
 
         # Indentation management
         self.indent_current_nsp = 0
 
         # Dict to track post-execution functions that have been registered
         self._post_execute = {}
 
     def init_environment(self):
         """Any changes we need to make to the user's environment."""
         pass
 
     def init_encoding(self):
         # Get system encoding at startup time.  Certain terminals (like Emacs
         # under Win32 have it set to None, and we need to have a known valid
         # encoding to use in the raw_input() method
         try:
             self.stdin_encoding = sys.stdin.encoding or 'ascii'
         except AttributeError:
             self.stdin_encoding = 'ascii'
 
     def init_syntax_highlighting(self):
         # Python source parser/formatter for syntax highlighting
         pyformat = PyColorize.Parser().format
         self.pycolorize = lambda src: pyformat(src,'str',self.colors)
 
     def init_pushd_popd_magic(self):
         # for pushd/popd management
         self.home_dir = get_home_dir()
 
         self.dir_stack = []
 
     def init_logger(self):
         self.logger = Logger(self.home_dir, logfname='ipython_log.py',
                              logmode='rotate')
 
     def init_logstart(self):
         """Initialize logging in case it was requested at the command line.
         """
         if self.logappend:
             self.magic('logstart %s append' % self.logappend)
         elif self.logfile:
             self.magic('logstart %s' % self.logfile)
         elif self.logstart:
             self.magic('logstart')
 
     def init_deprecation_warnings(self):
         """
         register default filter for deprecation warning.
 
         This will allow deprecation warning of function used interactively to show
         warning to users, and still hide deprecation warning from libraries import.
         """
         warnings.filterwarnings("default", category=DeprecationWarning, module=self.user_ns.get("__name__"))
 
     def init_builtins(self):
         # A single, static flag that we set to True.  Its presence indicates
         # that an IPython shell has been created, and we make no attempts at
         # removing on exit or representing the existence of more than one
         # IPython at a time.
         builtin_mod.__dict__['__IPYTHON__'] = True
 
         self.builtin_trap = BuiltinTrap(shell=self)
 
     def init_inspector(self):
         # Object inspector
         self.inspector = oinspect.Inspector(oinspect.InspectColors,
                                             PyColorize.ANSICodeColors,
                                             'NoColor',
                                             self.object_info_string_level)
 
     def init_io(self):
         # This will just use sys.stdout and sys.stderr. If you want to
         # override sys.stdout and sys.stderr themselves, you need to do that
         # *before* instantiating this class, because io holds onto
         # references to the underlying streams.
         if (sys.platform == 'win32' or sys.platform == 'cli') and self.has_readline:
             io.stdout = io.stderr = io.IOStream(self.readline._outputfile)
         else:
             io.stdout = io.IOStream(sys.stdout)
             io.stderr = io.IOStream(sys.stderr)
 
     def init_prompts(self):
         # Set system prompts, so that scripts can decide if they are running
         # interactively.
         sys.ps1 = 'In : '
         sys.ps2 = '...: '
         sys.ps3 = 'Out: '
 
     def init_display_formatter(self):
         self.display_formatter = DisplayFormatter(parent=self)
         self.configurables.append(self.display_formatter)
 
     def init_display_pub(self):
         self.display_pub = self.display_pub_class(parent=self)
         self.configurables.append(self.display_pub)
 
     def init_data_pub(self):
         if not self.data_pub_class:
             self.data_pub = None
             return
         self.data_pub = self.data_pub_class(parent=self)
         self.configurables.append(self.data_pub)
 
     def init_displayhook(self):
         # Initialize displayhook, set in/out prompts and printing system
         self.displayhook = self.displayhook_class(
             parent=self,
             shell=self,
             cache_size=self.cache_size,
         )
         self.configurables.append(self.displayhook)
         # This is a context manager that installs/revmoes the displayhook at
         # the appropriate time.
         self.display_trap = DisplayTrap(hook=self.displayhook)
 
     def init_virtualenv(self):
         """Add a virtualenv to sys.path so the user can import modules from it.
         This isn't perfect: it doesn't use the Python interpreter with which the
         virtualenv was built, and it ignores the --no-site-packages option. A
         warning will appear suggesting the user installs IPython in the
         virtualenv, but for many cases, it probably works well enough.
         
         Adapted from code snippets online.
         
         http://blog.ufsoft.org/2009/1/29/ipython-and-virtualenv
         """
         if 'VIRTUAL_ENV' not in os.environ:
             # Not in a virtualenv
             return
         
         # venv detection:
         # stdlib venv may symlink sys.executable, so we can't use realpath.
         # but others can symlink *to* the venv Python, so we can't just use sys.executable.
         # So we just check every item in the symlink tree (generally <= 3)
         p = os.path.normcase(sys.executable)
         paths = [p]
         while os.path.islink(p):
             p = os.path.normcase(os.path.join(os.path.dirname(p), os.readlink(p)))
             paths.append(p)
         p_venv = os.path.normcase(os.environ['VIRTUAL_ENV'])
         if any(p.startswith(p_venv) for p in paths):
             # Running properly in the virtualenv, don't need to do anything
             return
         
         warn("Attempting to work in a virtualenv. If you encounter problems, please "
              "install IPython inside the virtualenv.")
         if sys.platform == "win32":
             virtual_env = os.path.join(os.environ['VIRTUAL_ENV'], 'Lib', 'site-packages') 
         else:
             virtual_env = os.path.join(os.environ['VIRTUAL_ENV'], 'lib',
                        'python%d.%d' % sys.version_info[:2], 'site-packages')
         
         import site
         sys.path.insert(0, virtual_env)
         site.addsitedir(virtual_env)
 
     #-------------------------------------------------------------------------
     # Things related to injections into the sys module
     #-------------------------------------------------------------------------
 
     def save_sys_module_state(self):
         """Save the state of hooks in the sys module.
 
         This has to be called after self.user_module is created.
         """
         self._orig_sys_module_state = {'stdin': sys.stdin,
                                        'stdout': sys.stdout,
                                        'stderr': sys.stderr,
                                        'excepthook': sys.excepthook}
         self._orig_sys_modules_main_name = self.user_module.__name__
         self._orig_sys_modules_main_mod = sys.modules.get(self.user_module.__name__)
 
     def restore_sys_module_state(self):
         """Restore the state of the sys module."""
         try:
             for k, v in iteritems(self._orig_sys_module_state):
                 setattr(sys, k, v)
         except AttributeError:
             pass
         # Reset what what done in self.init_sys_modules
         if self._orig_sys_modules_main_mod is not None:
             sys.modules[self._orig_sys_modules_main_name] = self._orig_sys_modules_main_mod
 
     #-------------------------------------------------------------------------
     # Things related to the banner
     #-------------------------------------------------------------------------
     
     @property
     def banner(self):
         banner = self.banner1
         if self.profile and self.profile != 'default':
             banner += '\nIPython profile: %s\n' % self.profile
         if self.banner2:
             banner += '\n' + self.banner2
         return banner
 
     def show_banner(self, banner=None):
         if banner is None:
             banner = self.banner
         sys.stdout.write(banner)
     
     #-------------------------------------------------------------------------
     # Things related to hooks
     #-------------------------------------------------------------------------
 
     def init_hooks(self):
         # hooks holds pointers used for user-side customizations
         self.hooks = Struct()
 
         self.strdispatchers = {}
 
         # Set all default hooks, defined in the IPython.hooks module.
         hooks = IPython.core.hooks
         for hook_name in hooks.__all__:
             # default hooks have priority 100, i.e. low; user hooks should have
             # 0-100 priority
             self.set_hook(hook_name,getattr(hooks,hook_name), 100, _warn_deprecated=False)
         
         if self.display_page:
             self.set_hook('show_in_pager', page.as_hook(page.display_page), 90)
     
     def set_hook(self,name,hook, priority=50, str_key=None, re_key=None,
                  _warn_deprecated=True):
         """set_hook(name,hook) -> sets an internal IPython hook.
 
         IPython exposes some of its internal API as user-modifiable hooks.  By
         adding your function to one of these hooks, you can modify IPython's
         behavior to call at runtime your own routines."""
 
         # At some point in the future, this should validate the hook before it
         # accepts it.  Probably at least check that the hook takes the number
         # of args it's supposed to.
 
         f = types.MethodType(hook,self)
 
         # check if the hook is for strdispatcher first
         if str_key is not None:
             sdp = self.strdispatchers.get(name, StrDispatch())
             sdp.add_s(str_key, f, priority )
             self.strdispatchers[name] = sdp
             return
         if re_key is not None:
             sdp = self.strdispatchers.get(name, StrDispatch())
             sdp.add_re(re.compile(re_key), f, priority )
             self.strdispatchers[name] = sdp
             return
 
         dp = getattr(self.hooks, name, None)
         if name not in IPython.core.hooks.__all__:
             print("Warning! Hook '%s' is not one of %s" % \
                   (name, IPython.core.hooks.__all__ ))
 
         if _warn_deprecated and (name in IPython.core.hooks.deprecated):
             alternative = IPython.core.hooks.deprecated[name]
             warn("Hook {} is deprecated. Use {} instead.".format(name, alternative))
 
         if not dp:
             dp = IPython.core.hooks.CommandChainDispatcher()
 
         try:
             dp.add(f,priority)
         except AttributeError:
             # it was not commandchain, plain old func - replace
             dp = f
 
         setattr(self.hooks,name, dp)
 
     #-------------------------------------------------------------------------
     # Things related to events
     #-------------------------------------------------------------------------
 
     def init_events(self):
         self.events = EventManager(self, available_events)
 
         self.events.register("pre_execute", self._clear_warning_registry)
 
     def register_post_execute(self, func):
         """DEPRECATED: Use ip.events.register('post_run_cell', func)
         
         Register a function for calling after code execution.
         """
         warn("ip.register_post_execute is deprecated, use "
              "ip.events.register('post_run_cell', func) instead.")
         self.events.register('post_run_cell', func)
     
     def _clear_warning_registry(self):
         # clear the warning registry, so that different code blocks with
         # overlapping line number ranges don't cause spurious suppression of
         # warnings (see gh-6611 for details)
         if "__warningregistry__" in self.user_global_ns:
             del self.user_global_ns["__warningregistry__"]
 
     #-------------------------------------------------------------------------
     # Things related to the "main" module
     #-------------------------------------------------------------------------
 
     def new_main_mod(self, filename, modname):
         """Return a new 'main' module object for user code execution.
         
         ``filename`` should be the path of the script which will be run in the
         module. Requests with the same filename will get the same module, with
         its namespace cleared.
         
         ``modname`` should be the module name - normally either '__main__' or
         the basename of the file without the extension.
         
         When scripts are executed via %run, we must keep a reference to their
         __main__ module around so that Python doesn't
         clear it, rendering references to module globals useless.
 
         This method keeps said reference in a private dict, keyed by the
         absolute path of the script. This way, for multiple executions of the
         same script we only keep one copy of the namespace (the last one),
         thus preventing memory leaks from old references while allowing the
         objects from the last execution to be accessible.
         """
         filename = os.path.abspath(filename)
         try:
             main_mod = self._main_mod_cache[filename]
         except KeyError:
             main_mod = self._main_mod_cache[filename] = types.ModuleType(
                         py3compat.cast_bytes_py2(modname),
                         doc="Module created for script run in IPython")
         else:
             main_mod.__dict__.clear()
             main_mod.__name__ = modname
         
         main_mod.__file__ = filename
         # It seems pydoc (and perhaps others) needs any module instance to
         # implement a __nonzero__ method
         main_mod.__nonzero__ = lambda : True
         
         return main_mod
 
     def clear_main_mod_cache(self):
         """Clear the cache of main modules.
 
         Mainly for use by utilities like %reset.
 
         Examples
         --------
 
         In [15]: import IPython
 
         In [16]: m = _ip.new_main_mod(IPython.__file__, 'IPython')
 
         In [17]: len(_ip._main_mod_cache) > 0
         Out[17]: True
 
         In [18]: _ip.clear_main_mod_cache()
 
         In [19]: len(_ip._main_mod_cache) == 0
         Out[19]: True
         """
         self._main_mod_cache.clear()
 
     #-------------------------------------------------------------------------
     # Things related to debugging
     #-------------------------------------------------------------------------
 
     def init_pdb(self):
         # Set calling of pdb on exceptions
         # self.call_pdb is a property
         self.call_pdb = self.pdb
 
     def _get_call_pdb(self):
         return self._call_pdb
 
     def _set_call_pdb(self,val):
 
         if val not in (0,1,False,True):
             raise ValueError('new call_pdb value must be boolean')
 
         # store value in instance
         self._call_pdb = val
 
         # notify the actual exception handlers
         self.InteractiveTB.call_pdb = val
 
     call_pdb = property(_get_call_pdb,_set_call_pdb,None,
                         'Control auto-activation of pdb at exceptions')
 
     def debugger(self,force=False):
         """Call the pdb debugger.
 
         Keywords:
 
           - force(False): by default, this routine checks the instance call_pdb
             flag and does not actually invoke the debugger if the flag is false.
             The 'force' option forces the debugger to activate even if the flag
             is false.
         """
 
         if not (force or self.call_pdb):
             return
 
         if not hasattr(sys,'last_traceback'):
             error('No traceback has been produced, nothing to debug.')
             return
 
 
         with self.readline_no_record:
             self.InteractiveTB.debugger(force=True)
 
     #-------------------------------------------------------------------------
     # Things related to IPython's various namespaces
     #-------------------------------------------------------------------------
     default_user_namespaces = True
 
     def init_create_namespaces(self, user_module=None, user_ns=None):
         # Create the namespace where the user will operate.  user_ns is
         # normally the only one used, and it is passed to the exec calls as
         # the locals argument.  But we do carry a user_global_ns namespace
         # given as the exec 'globals' argument,  This is useful in embedding
         # situations where the ipython shell opens in a context where the
         # distinction between locals and globals is meaningful.  For
         # non-embedded contexts, it is just the same object as the user_ns dict.
 
         # FIXME. For some strange reason, __builtins__ is showing up at user
         # level as a dict instead of a module. This is a manual fix, but I
         # should really track down where the problem is coming from. Alex
         # Schmolck reported this problem first.
 
         # A useful post by Alex Martelli on this topic:
         # Re: inconsistent value from __builtins__
         # Von: Alex Martelli <[e-mail]>
         # Datum: Freitag 01 Oktober 2004 04:45:34 nachmittags/abends
         # Gruppen: comp.lang.python
 
         # Michael Hohn <[e-mail]> wrote:
         # > >>> print type(builtin_check.get_global_binding('__builtins__'))
         # > <type 'dict'>
         # > >>> print type(__builtins__)
         # > <type 'module'>
         # > Is this difference in return value intentional?
 
         # Well, it's documented that '__builtins__' can be either a dictionary
         # or a module, and it's been that way for a long time. Whether it's
         # intentional (or sensible), I don't know. In any case, the idea is
         # that if you need to access the built-in namespace directly, you
         # should start with "import __builtin__" (note, no 's') which will
         # definitely give you a module. Yeah, it's somewhat confusing:-(.
 
         # These routines return a properly built module and dict as needed by
         # the rest of the code, and can also be used by extension writers to
         # generate properly initialized namespaces.
         if (user_ns is not None) or (user_module is not None):
             self.default_user_namespaces = False
         self.user_module, self.user_ns = self.prepare_user_module(user_module, user_ns)
 
         # A record of hidden variables we have added to the user namespace, so
         # we can list later only variables defined in actual interactive use.
         self.user_ns_hidden = {}
 
         # Now that FakeModule produces a real module, we've run into a nasty
         # problem: after script execution (via %run), the module where the user
         # code ran is deleted.  Now that this object is a true module (needed
         # so doctest and other tools work correctly), the Python module
         # teardown mechanism runs over it, and sets to None every variable
         # present in that module.  Top-level references to objects from the
         # script survive, because the user_ns is updated with them.  However,
         # calling functions defined in the script that use other things from
         # the script will fail, because the function's closure had references
         # to the original objects, which are now all None.  So we must protect
         # these modules from deletion by keeping a cache.
         #
         # To avoid keeping stale modules around (we only need the one from the
         # last run), we use a dict keyed with the full path to the script, so
         # only the last version of the module is held in the cache.  Note,
         # however, that we must cache the module *namespace contents* (their
         # __dict__).  Because if we try to cache the actual modules, old ones
         # (uncached) could be destroyed while still holding references (such as
         # those held by GUI objects that tend to be long-lived)>
         #
         # The %reset command will flush this cache.  See the cache_main_mod()
         # and clear_main_mod_cache() methods for details on use.
 
         # This is the cache used for 'main' namespaces
         self._main_mod_cache = {}
 
         # A table holding all the namespaces IPython deals with, so that
         # introspection facilities can search easily.
         self.ns_table = {'user_global':self.user_module.__dict__,
                          'user_local':self.user_ns,
                          'builtin':builtin_mod.__dict__
                          }
     
     @property
     def user_global_ns(self):
         return self.user_module.__dict__
 
     def prepare_user_module(self, user_module=None, user_ns=None):
         """Prepare the module and namespace in which user code will be run.
         
         When IPython is started normally, both parameters are None: a new module
         is created automatically, and its __dict__ used as the namespace.
         
         If only user_module is provided, its __dict__ is used as the namespace.
         If only user_ns is provided, a dummy module is created, and user_ns
         becomes the global namespace. If both are provided (as they may be
         when embedding), user_ns is the local namespace, and user_module
         provides the global namespace.
 
         Parameters
         ----------
         user_module : module, optional
             The current user module in which IPython is being run. If None,
             a clean module will be created.
         user_ns : dict, optional
             A namespace in which to run interactive commands.
 
         Returns
         -------
         A tuple of user_module and user_ns, each properly initialised.
         """
         if user_module is None and user_ns is not None:
             user_ns.setdefault("__name__", "__main__")
             user_module = DummyMod()
             user_module.__dict__ = user_ns
             
         if user_module is None:
             user_module = types.ModuleType("__main__",
                 doc="Automatically created module for IPython interactive environment")
         
         # We must ensure that __builtin__ (without the final 's') is always
         # available and pointing to the __builtin__ *module*.  For more details:
         # http://mail.python.org/pipermail/python-dev/2001-April/014068.html
         user_module.__dict__.setdefault('__builtin__', builtin_mod)
         user_module.__dict__.setdefault('__builtins__', builtin_mod)
         
         if user_ns is None:
             user_ns = user_module.__dict__
 
         return user_module, user_ns
 
     def init_sys_modules(self):
         # We need to insert into sys.modules something that looks like a
         # module but which accesses the IPython namespace, for shelve and
         # pickle to work interactively. Normally they rely on getting
         # everything out of __main__, but for embedding purposes each IPython
         # instance has its own private namespace, so we can't go shoving
         # everything into __main__.
 
         # note, however, that we should only do this for non-embedded
         # ipythons, which really mimic the __main__.__dict__ with their own
         # namespace.  Embedded instances, on the other hand, should not do
         # this because they need to manage the user local/global namespaces
         # only, but they live within a 'normal' __main__ (meaning, they
         # shouldn't overtake the execution environment of the script they're
         # embedded in).
 
         # This is overridden in the InteractiveShellEmbed subclass to a no-op.
         main_name = self.user_module.__name__
         sys.modules[main_name] = self.user_module
 
     def init_user_ns(self):
         """Initialize all user-visible namespaces to their minimum defaults.
 
         Certain history lists are also initialized here, as they effectively
         act as user namespaces.
 
         Notes
         -----
         All data structures here are only filled in, they are NOT reset by this
         method.  If they were not empty before, data will simply be added to
         therm.
         """
         # This function works in two parts: first we put a few things in
         # user_ns, and we sync that contents into user_ns_hidden so that these
         # initial variables aren't shown by %who.  After the sync, we add the
         # rest of what we *do* want the user to see with %who even on a new
         # session (probably nothing, so they really only see their own stuff)
 
         # The user dict must *always* have a __builtin__ reference to the
         # Python standard __builtin__ namespace,  which must be imported.
         # This is so that certain operations in prompt evaluation can be
         # reliably executed with builtins.  Note that we can NOT use
         # __builtins__ (note the 's'),  because that can either be a dict or a
         # module, and can even mutate at runtime, depending on the context
         # (Python makes no guarantees on it).  In contrast, __builtin__ is
         # always a module object, though it must be explicitly imported.
 
         # For more details:
         # http://mail.python.org/pipermail/python-dev/2001-April/014068.html
         ns = dict()
         
         # make global variables for user access to the histories
         ns['_ih'] = self.history_manager.input_hist_parsed
         ns['_oh'] = self.history_manager.output_hist
         ns['_dh'] = self.history_manager.dir_hist
 
         ns['_sh'] = shadowns
 
         # user aliases to input and output histories.  These shouldn't show up
         # in %who, as they can have very large reprs.
         ns['In']  = self.history_manager.input_hist_parsed
         ns['Out'] = self.history_manager.output_hist
 
         # Store myself as the public api!!!
         ns['get_ipython'] = self.get_ipython
         
         ns['exit'] = self.exiter
         ns['quit'] = self.exiter
 
         # Sync what we've added so far to user_ns_hidden so these aren't seen
         # by %who
         self.user_ns_hidden.update(ns)
 
         # Anything put into ns now would show up in %who.  Think twice before
         # putting anything here, as we really want %who to show the user their
         # stuff, not our variables.
 
         # Finally, update the real user's namespace
         self.user_ns.update(ns)
     
     @property
     def all_ns_refs(self):
         """Get a list of references to all the namespace dictionaries in which
         IPython might store a user-created object.
         
         Note that this does not include the displayhook, which also caches
         objects from the output."""
         return [self.user_ns, self.user_global_ns, self.user_ns_hidden] + \
                [m.__dict__ for m in self._main_mod_cache.values()]
 
     def reset(self, new_session=True):
         """Clear all internal namespaces, and attempt to release references to
         user objects.
 
         If new_session is True, a new history session will be opened.
         """
         # Clear histories
         self.history_manager.reset(new_session)
         # Reset counter used to index all histories
         if new_session:
             self.execution_count = 1
 
         # Flush cached output items
         if self.displayhook.do_full_cache:
             self.displayhook.flush()
 
         # The main execution namespaces must be cleared very carefully,
         # skipping the deletion of the builtin-related keys, because doing so
         # would cause errors in many object's __del__ methods.
         if self.user_ns is not self.user_global_ns:
             self.user_ns.clear()
         ns = self.user_global_ns
         drop_keys = set(ns.keys())
         drop_keys.discard('__builtin__')
         drop_keys.discard('__builtins__')
         drop_keys.discard('__name__')
         for k in drop_keys:
             del ns[k]
         
         self.user_ns_hidden.clear()
         
         # Restore the user namespaces to minimal usability
         self.init_user_ns()
 
         # Restore the default and user aliases
         self.alias_manager.clear_aliases()
         self.alias_manager.init_aliases()
 
         # Flush the private list of module references kept for script
         # execution protection
         self.clear_main_mod_cache()
 
     def del_var(self, varname, by_name=False):
         """Delete a variable from the various namespaces, so that, as
         far as possible, we're not keeping any hidden references to it.
 
         Parameters
         ----------
         varname : str
             The name of the variable to delete.
         by_name : bool
             If True, delete variables with the given name in each
             namespace. If False (default), find the variable in the user
             namespace, and delete references to it.
         """
         if varname in ('__builtin__', '__builtins__'):
             raise ValueError("Refusing to delete %s" % varname)
 
         ns_refs = self.all_ns_refs
         
         if by_name:                    # Delete by name
             for ns in ns_refs:
                 try:
                     del ns[varname]
                 except KeyError:
                     pass
         else:                         # Delete by object
             try:
                 obj = self.user_ns[varname]
             except KeyError:
                 raise NameError("name '%s' is not defined" % varname)
             # Also check in output history
             ns_refs.append(self.history_manager.output_hist)
             for ns in ns_refs:
                 to_delete = [n for n, o in iteritems(ns) if o is obj]
                 for name in to_delete:
                     del ns[name]
 
             # displayhook keeps extra references, but not in a dictionary
             for name in ('_', '__', '___'):
                 if getattr(self.displayhook, name) is obj:
                     setattr(self.displayhook, name, None)
 
     def reset_selective(self, regex=None):
         """Clear selective variables from internal namespaces based on a
         specified regular expression.
 
         Parameters
         ----------
         regex : string or compiled pattern, optional
             A regular expression pattern that will be used in searching
             variable names in the users namespaces.
         """
         if regex is not None:
             try:
                 m = re.compile(regex)
             except TypeError:
                 raise TypeError('regex must be a string or compiled pattern')
             # Search for keys in each namespace that match the given regex
             # If a match is found, delete the key/value pair.
             for ns in self.all_ns_refs:
                 for var in ns:
                     if m.search(var):
                         del ns[var]
 
     def push(self, variables, interactive=True):
         """Inject a group of variables into the IPython user namespace.
 
         Parameters
         ----------
         variables : dict, str or list/tuple of str
             The variables to inject into the user's namespace.  If a dict, a
             simple update is done.  If a str, the string is assumed to have
             variable names separated by spaces.  A list/tuple of str can also
             be used to give the variable names.  If just the variable names are
             give (list/tuple/str) then the variable values looked up in the
             callers frame.
         interactive : bool
             If True (default), the variables will be listed with the ``who``
             magic.
         """
         vdict = None
 
         # We need a dict of name/value pairs to do namespace updates.
         if isinstance(variables, dict):
             vdict = variables
         elif isinstance(variables, string_types+(list, tuple)):
             if isinstance(variables, string_types):
                 vlist = variables.split()
             else:
                 vlist = variables
             vdict = {}
             cf = sys._getframe(1)
             for name in vlist:
                 try:
                     vdict[name] = eval(name, cf.f_globals, cf.f_locals)
                 except:
                     print('Could not get variable %s from %s' %
                            (name,cf.f_code.co_name))
         else:
             raise ValueError('variables must be a dict/str/list/tuple')
 
         # Propagate variables to user namespace
         self.user_ns.update(vdict)
 
         # And configure interactive visibility
         user_ns_hidden = self.user_ns_hidden
         if interactive:
             for name in vdict:
                 user_ns_hidden.pop(name, None)
         else:
             user_ns_hidden.update(vdict)
     
     def drop_by_id(self, variables):
         """Remove a dict of variables from the user namespace, if they are the
         same as the values in the dictionary.
         
         This is intended for use by extensions: variables that they've added can
         be taken back out if they are unloaded, without removing any that the
         user has overwritten.
         
         Parameters
         ----------
         variables : dict
           A dictionary mapping object names (as strings) to the objects.
         """
         for name, obj in iteritems(variables):
             if name in self.user_ns and self.user_ns[name] is obj:
                 del self.user_ns[name]
                 self.user_ns_hidden.pop(name, None)
 
     #-------------------------------------------------------------------------
     # Things related to object introspection
     #-------------------------------------------------------------------------
 
     def _ofind(self, oname, namespaces=None):
         """Find an object in the available namespaces.
 
         self._ofind(oname) -> dict with keys: found,obj,ospace,ismagic
 
         Has special code to detect magic functions.
         """
         oname = oname.strip()
         #print '1- oname: <%r>' % oname  # dbg
         if not oname.startswith(ESC_MAGIC) and \
             not oname.startswith(ESC_MAGIC2) and \
             not py3compat.isidentifier(oname, dotted=True):
             return dict(found=False)
 
         if namespaces is None:
             # Namespaces to search in:
             # Put them in a list. The order is important so that we
             # find things in the same order that Python finds them.
             namespaces = [ ('Interactive', self.user_ns),
                            ('Interactive (global)', self.user_global_ns),
                            ('Python builtin', builtin_mod.__dict__),
                            ]
 
         # initialize results to 'null'
         found = False; obj = None;  ospace = None;
         ismagic = False; isalias = False; parent = None
 
         # We need to special-case 'print', which as of python2.6 registers as a
         # function but should only be treated as one if print_function was
         # loaded with a future import.  In this case, just bail.
         if (oname == 'print' and not py3compat.PY3 and not \
             (self.compile.compiler_flags & __future__.CO_FUTURE_PRINT_FUNCTION)):
             return {'found':found, 'obj':obj, 'namespace':ospace,
                     'ismagic':ismagic, 'isalias':isalias, 'parent':parent}
 
         # Look for the given name by splitting it in parts.  If the head is
         # found, then we look for all the remaining parts as members, and only
         # declare success if we can find them all.
         oname_parts = oname.split('.')
         oname_head, oname_rest = oname_parts[0],oname_parts[1:]
         for nsname,ns in namespaces:
             try:
                 obj = ns[oname_head]
             except KeyError:
                 continue
             else:
                 #print 'oname_rest:', oname_rest  # dbg
                 for idx, part in enumerate(oname_rest):
                     try:
                         parent = obj
                         # The last part is looked up in a special way to avoid
                         # descriptor invocation as it may raise or have side
                         # effects.
                         if idx == len(oname_rest) - 1:
                             obj = self._getattr_property(obj, part)
                         else:
                             obj = getattr(obj, part)
                     except:
                         # Blanket except b/c some badly implemented objects
                         # allow __getattr__ to raise exceptions other than
                         # AttributeError, which then crashes IPython.
                         break
                 else:
                     # If we finish the for loop (no break), we got all members
                     found = True
                     ospace = nsname
                     break  # namespace loop
 
         # Try to see if it's magic
         if not found:
             obj = None
             if oname.startswith(ESC_MAGIC2):
                 oname = oname.lstrip(ESC_MAGIC2)
                 obj = self.find_cell_magic(oname)
             elif oname.startswith(ESC_MAGIC):
                 oname = oname.lstrip(ESC_MAGIC)
                 obj = self.find_line_magic(oname)
             else:
                 # search without prefix, so run? will find %run?
                 obj = self.find_line_magic(oname)
                 if obj is None:
                     obj = self.find_cell_magic(oname)
             if obj is not None:
                 found = True
                 ospace = 'IPython internal'
                 ismagic = True
                 isalias = isinstance(obj, Alias)
 
         # Last try: special-case some literals like '', [], {}, etc:
         if not found and oname_head in ["''",'""','[]','{}','()']:
             obj = eval(oname_head)
             found = True
             ospace = 'Interactive'
 
         return {'found':found, 'obj':obj, 'namespace':ospace,
                 'ismagic':ismagic, 'isalias':isalias, 'parent':parent}
 
     @staticmethod
     def _getattr_property(obj, attrname):
         """Property-aware getattr to use in object finding.
 
         If attrname represents a property, return it unevaluated (in case it has
         side effects or raises an error.
 
         """
         if not isinstance(obj, type):
             try:
                 # `getattr(type(obj), attrname)` is not guaranteed to return
                 # `obj`, but does so for property:
                 #
                 # property.__get__(self, None, cls) -> self
                 #
                 # The universal alternative is to traverse the mro manually
                 # searching for attrname in class dicts.
                 attr = getattr(type(obj), attrname)
             except AttributeError:
                 pass
             else:
                 # This relies on the fact that data descriptors (with both
                 # __get__ & __set__ magic methods) take precedence over
                 # instance-level attributes:
                 #
                 #    class A(object):
                 #        @property
                 #        def foobar(self): return 123
                 #    a = A()
                 #    a.__dict__['foobar'] = 345
                 #    a.foobar  # == 123
                 #
                 # So, a property may be returned right away.
                 if isinstance(attr, property):
                     return attr
 
         # Nothing helped, fall back.
         return getattr(obj, attrname)
 
     def _object_find(self, oname, namespaces=None):
         """Find an object and return a struct with info about it."""
         return Struct(self._ofind(oname, namespaces))
 
     def _inspect(self, meth, oname, namespaces=None, **kw):
         """Generic interface to the inspector system.
 
         This function is meant to be called by pdef, pdoc & friends."""
         info = self._object_find(oname, namespaces)
         if info.found:
             pmethod = getattr(self.inspector, meth)
             formatter = format_screen if info.ismagic else None
             if meth == 'pdoc':
                 pmethod(info.obj, oname, formatter)
             elif meth == 'pinfo':
                 pmethod(info.obj, oname, formatter, info, **kw)
             else:
                 pmethod(info.obj, oname)
         else:
             print('Object `%s` not found.' % oname)
             return 'not found'  # so callers can take other action
 
     def object_inspect(self, oname, detail_level=0):
         """Get object info about oname"""
         with self.builtin_trap:
             info = self._object_find(oname)
             if info.found:
                 return self.inspector.info(info.obj, oname, info=info,
                             detail_level=detail_level
                 )
             else:
                 return oinspect.object_info(name=oname, found=False)
 
     def object_inspect_text(self, oname, detail_level=0):
         """Get object info as formatted text"""
         with self.builtin_trap:
             info = self._object_find(oname)
             if info.found:
                 return self.inspector._format_info(info.obj, oname, info=info,
                             detail_level=detail_level
                 )
             else:
                 raise KeyError(oname)
 
     #-------------------------------------------------------------------------
     # Things related to history management
     #-------------------------------------------------------------------------
 
     def init_history(self):
         """Sets up the command history, and starts regular autosaves."""
         self.history_manager = HistoryManager(shell=self, parent=self)
         self.configurables.append(self.history_manager)
 
     #-------------------------------------------------------------------------
     # Things related to exception handling and tracebacks (not debugging)
     #-------------------------------------------------------------------------
 
     debugger_cls = Pdb
 
     def init_traceback_handlers(self, custom_exceptions):
         # Syntax error handler.
         self.SyntaxTB = ultratb.SyntaxTB(color_scheme='NoColor')
 
         # The interactive one is initialized with an offset, meaning we always
         # want to remove the topmost item in the traceback, which is our own
         # internal code. Valid modes: ['Plain','Context','Verbose']
         self.InteractiveTB = ultratb.AutoFormattedTB(mode = 'Plain',
                                                      color_scheme='NoColor',
                                                      tb_offset = 1,
                                    check_cache=check_linecache_ipython,
                                    debugger_cls=self.debugger_cls)
 
         # The instance will store a pointer to the system-wide exception hook,
         # so that runtime code (such as magics) can access it.  This is because
         # during the read-eval loop, it may get temporarily overwritten.
         self.sys_excepthook = sys.excepthook
 
         # and add any custom exception handlers the user may have specified
         self.set_custom_exc(*custom_exceptions)
 
         # Set the exception mode
         self.InteractiveTB.set_mode(mode=self.xmode)
 
     def set_custom_exc(self, exc_tuple, handler):
         """set_custom_exc(exc_tuple, handler)
 
         Set a custom exception handler, which will be called if any of the
         exceptions in exc_tuple occur in the mainloop (specifically, in the
         run_code() method).
 
         Parameters
         ----------
 
         exc_tuple : tuple of exception classes
             A *tuple* of exception classes, for which to call the defined
             handler.  It is very important that you use a tuple, and NOT A
             LIST here, because of the way Python's except statement works.  If
             you only want to trap a single exception, use a singleton tuple::
 
                 exc_tuple == (MyCustomException,)
 
         handler : callable
             handler must have the following signature::
 
                 def my_handler(self, etype, value, tb, tb_offset=None):
                     ...
                     return structured_traceback
 
             Your handler must return a structured traceback (a list of strings),
             or None.
 
             This will be made into an instance method (via types.MethodType)
             of IPython itself, and it will be called if any of the exceptions
             listed in the exc_tuple are caught. If the handler is None, an
             internal basic one is used, which just prints basic info.
 
             To protect IPython from crashes, if your handler ever raises an
             exception or returns an invalid result, it will be immediately
             disabled.
 
         WARNING: by putting in your own exception handler into IPython's main
         execution loop, you run a very good chance of nasty crashes.  This
         facility should only be used if you really know what you are doing."""
 
         assert type(exc_tuple)==type(()) , \
                "The custom exceptions must be given AS A TUPLE."
 
         def dummy_handler(self, etype, value, tb, tb_offset=None):
             print('*** Simple custom exception handler ***')
             print('Exception type :',etype)
             print('Exception value:',value)
             print('Traceback      :',tb)
             #print 'Source code    :','\n'.join(self.buffer)
         
         def validate_stb(stb):
             """validate structured traceback return type
             
             return type of CustomTB *should* be a list of strings, but allow
             single strings or None, which are harmless.
             
             This function will *always* return a list of strings,
             and will raise a TypeError if stb is inappropriate.
             """
             msg = "CustomTB must return list of strings, not %r" % stb
             if stb is None:
                 return []
             elif isinstance(stb, string_types):
                 return [stb]
             elif not isinstance(stb, list):
                 raise TypeError(msg)
             # it's a list
             for line in stb:
                 # check every element
                 if not isinstance(line, string_types):
                     raise TypeError(msg)
             return stb
 
         if handler is None:
             wrapped = dummy_handler
         else:
             def wrapped(self,etype,value,tb,tb_offset=None):
                 """wrap CustomTB handler, to protect IPython from user code
                 
                 This makes it harder (but not impossible) for custom exception
                 handlers to crash IPython.
                 """
                 try:
                     stb = handler(self,etype,value,tb,tb_offset=tb_offset)
                     return validate_stb(stb)
                 except:
                     # clear custom handler immediately
                     self.set_custom_exc((), None)
                     print("Custom TB Handler failed, unregistering", file=sys.stderr)
                     # show the exception in handler first
                     stb = self.InteractiveTB.structured_traceback(*sys.exc_info())
                     print(self.InteractiveTB.stb2text(stb))
                     print("The original exception:")
                     stb = self.InteractiveTB.structured_traceback(
                                             (etype,value,tb), tb_offset=tb_offset
                     )
                 return stb
 
         self.CustomTB = types.MethodType(wrapped,self)
         self.custom_exceptions = exc_tuple
 
     def excepthook(self, etype, value, tb):
       """One more defense for GUI apps that call sys.excepthook.
 
       GUI frameworks like wxPython trap exceptions and call
       sys.excepthook themselves.  I guess this is a feature that
       enables them to keep running after exceptions that would
       otherwise kill their mainloop. This is a bother for IPython
       which excepts to catch all of the program exceptions with a try:
       except: statement.
 
       Normally, IPython sets sys.excepthook to a CrashHandler instance, so if
       any app directly invokes sys.excepthook, it will look to the user like
       IPython crashed.  In order to work around this, we can disable the
       CrashHandler and replace it with this excepthook instead, which prints a
       regular traceback using our InteractiveTB.  In this fashion, apps which
       call sys.excepthook will generate a regular-looking exception from
       IPython, and the CrashHandler will only be triggered by real IPython
       crashes.
 
       This hook should be used sparingly, only in places which are not likely
       to be true IPython errors.
       """
       self.showtraceback((etype, value, tb), tb_offset=0)
 
     def _get_exc_info(self, exc_tuple=None):
         """get exc_info from a given tuple, sys.exc_info() or sys.last_type etc.
         
         Ensures sys.last_type,value,traceback hold the exc_info we found,
         from whichever source.
         
         raises ValueError if none of these contain any information
         """
         if exc_tuple is None:
             etype, value, tb = sys.exc_info()
         else:
             etype, value, tb = exc_tuple
 
         if etype is None:
             if hasattr(sys, 'last_type'):
                 etype, value, tb = sys.last_type, sys.last_value, \
                                    sys.last_traceback
         
         if etype is None:
             raise ValueError("No exception to find")
         
         # Now store the exception info in sys.last_type etc.
         # WARNING: these variables are somewhat deprecated and not
         # necessarily safe to use in a threaded environment, but tools
         # like pdb depend on their existence, so let's set them.  If we
         # find problems in the field, we'll need to revisit their use.
         sys.last_type = etype
         sys.last_value = value
         sys.last_traceback = tb
         
         return etype, value, tb
     
     def show_usage_error(self, exc):
         """Show a short message for UsageErrors
         
         These are special exceptions that shouldn't show a traceback.
         """
         print("UsageError: %s" % exc, file=sys.stderr)
     
     def get_exception_only(self, exc_tuple=None):
         """
         Return as a string (ending with a newline) the exception that
         just occurred, without any traceback.
         """
         etype, value, tb = self._get_exc_info(exc_tuple)
         msg = traceback.format_exception_only(etype, value)
         return ''.join(msg)
 
     def showtraceback(self, exc_tuple=None, filename=None, tb_offset=None,
                       exception_only=False):
         """Display the exception that just occurred.
 
         If nothing is known about the exception, this is the method which
         should be used throughout the code for presenting user tracebacks,
         rather than directly invoking the InteractiveTB object.
 
         A specific showsyntaxerror() also exists, but this method can take
         care of calling it if needed, so unless you are explicitly catching a
         SyntaxError exception, don't try to analyze the stack manually and
         simply call this method."""
 
         try:
             try:
                 etype, value, tb = self._get_exc_info(exc_tuple)
             except ValueError:
                 print('No traceback available to show.', file=sys.stderr)
                 return
             
             if issubclass(etype, SyntaxError):
                 # Though this won't be called by syntax errors in the input
                 # line, there may be SyntaxError cases with imported code.
                 self.showsyntaxerror(filename)
             elif etype is UsageError:
                 self.show_usage_error(value)
             else:
                 if exception_only:
                     stb = ['An exception has occurred, use %tb to see '
                            'the full traceback.\n']
                     stb.extend(self.InteractiveTB.get_exception_only(etype,
                                                                      value))
                 else:
                     try:
                         # Exception classes can customise their traceback - we
                         # use this in IPython.parallel for exceptions occurring
                         # in the engines. This should return a list of strings.
                         stb = value._render_traceback_()
                     except Exception:
                         stb = self.InteractiveTB.structured_traceback(etype,
                                             value, tb, tb_offset=tb_offset)
 
                     self._showtraceback(etype, value, stb)
                     if self.call_pdb:
                         # drop into debugger
                         self.debugger(force=True)
                     return
 
                 # Actually show the traceback
                 self._showtraceback(etype, value, stb)
 
         except KeyboardInterrupt:
             print('\n' + self.get_exception_only(), file=sys.stderr)
 
     def _showtraceback(self, etype, evalue, stb):
         """Actually show a traceback.
 
         Subclasses may override this method to put the traceback on a different
         place, like a side channel.
         """
         print(self.InteractiveTB.stb2text(stb))
 
     def showsyntaxerror(self, filename=None):
         """Display the syntax error that just occurred.
 
         This doesn't display a stack trace because there isn't one.
 
         If a filename is given, it is stuffed in the exception instead
         of what was there before (because Python's parser always uses
         "<string>" when reading from a string).
         """
         etype, value, last_traceback = self._get_exc_info()
 
         if filename and issubclass(etype, SyntaxError):
             try:
                 value.filename = filename
             except:
                 # Not the format we expect; leave it alone
                 pass
         
         stb = self.SyntaxTB.structured_traceback(etype, value, [])
         self._showtraceback(etype, value, stb)
 
     # This is overridden in TerminalInteractiveShell to show a message about
     # the %paste magic.
     def showindentationerror(self):
         """Called by run_cell when there's an IndentationError in code entered
         at the prompt.
 
         This is overridden in TerminalInteractiveShell to show a message about
         the %paste magic."""
         self.showsyntaxerror()
 
     #-------------------------------------------------------------------------
     # Things related to readline
     #-------------------------------------------------------------------------
 
     def init_readline(self):
         """Moved to terminal subclass, here only to simplify the init logic."""
         self.readline = None
         # Set a number of methods that depend on readline to be no-op
         self.readline_no_record = NoOpContext()
         self.set_readline_completer = no_op
         self.set_custom_completer = no_op
 
     @skip_doctest
     def set_next_input(self, s, replace=False):
         """ Sets the 'default' input string for the next command line.
 
         Example::
 
             In [1]: _ip.set_next_input("Hello Word")
             In [2]: Hello Word_  # cursor is here
         """
         self.rl_next_input = py3compat.cast_bytes_py2(s)
 
     def _indent_current_str(self):
         """return the current level of indentation as a string"""
         return self.input_splitter.indent_spaces * ' '
 
     #-------------------------------------------------------------------------
     # Things related to text completion
     #-------------------------------------------------------------------------
 
     def init_completer(self):
         """Initialize the completion machinery.
 
         This creates completion machinery that can be used by client code,
         either interactively in-process (typically triggered by the readline
         library), programmatically (such as in test suites) or out-of-process
         (typically over the network by remote frontends).
         """
         from IPython.core.completer import IPCompleter
         from IPython.core.completerlib import (module_completer,
                 magic_run_completer, cd_completer, reset_completer)
 
         self.Completer = IPCompleter(shell=self,
                                      namespace=self.user_ns,
                                      global_namespace=self.user_global_ns,
                                      use_readline=self.has_readline,
                                      parent=self,
                                      )
         self.configurables.append(self.Completer)
 
         # Add custom completers to the basic ones built into IPCompleter
         sdisp = self.strdispatchers.get('complete_command', StrDispatch())
         self.strdispatchers['complete_command'] = sdisp
         self.Completer.custom_completers = sdisp
 
         self.set_hook('complete_command', module_completer, str_key = 'import')
         self.set_hook('complete_command', module_completer, str_key = 'from')
         self.set_hook('complete_command', module_completer, str_key = '%aimport')
         self.set_hook('complete_command', magic_run_completer, str_key = '%run')
         self.set_hook('complete_command', cd_completer, str_key = '%cd')
         self.set_hook('complete_command', reset_completer, str_key = '%reset')
 
 
     @skip_doctest_py2
     def complete(self, text, line=None, cursor_pos=None):
         """Return the completed text and a list of completions.
 
         Parameters
         ----------
 
            text : string
              A string of text to be completed on.  It can be given as empty and
              instead a line/position pair are given.  In this case, the
              completer itself will split the line like readline does.
 
            line : string, optional
              The complete line that text is part of.
 
            cursor_pos : int, optional
              The position of the cursor on the input line.
 
         Returns
         -------
           text : string
             The actual text that was completed.
 
           matches : list
             A sorted list with all possible completions.
 
         The optional arguments allow the completion to take more context into
         account, and are part of the low-level completion API.
 
         This is a wrapper around the completion mechanism, similar to what
         readline does at the command line when the TAB key is hit.  By
         exposing it as a method, it can be used by other non-readline
         environments (such as GUIs) for text completion.
 
         Simple usage example:
 
         In [1]: x = 'hello'
 
         In [2]: _ip.complete('x.l')
         Out[2]: ('x.l', ['x.ljust', 'x.lower', 'x.lstrip'])
         """
 
         # Inject names into __builtin__ so we can complete on the added names.
         with self.builtin_trap:
             return self.Completer.complete(text, line, cursor_pos)
 
     def set_custom_completer(self, completer, pos=0):
         """Adds a new custom completer function.
 
         The position argument (defaults to 0) is the index in the completers
         list where you want the completer to be inserted."""
 
         newcomp = types.MethodType(completer,self.Completer)
         self.Completer.matchers.insert(pos,newcomp)
 
     def set_completer_frame(self, frame=None):
         """Set the frame of the completer."""
         if frame:
             self.Completer.namespace = frame.f_locals
             self.Completer.global_namespace = frame.f_globals
         else:
             self.Completer.namespace = self.user_ns
             self.Completer.global_namespace = self.user_global_ns
 
     #-------------------------------------------------------------------------
     # Things related to magics
     #-------------------------------------------------------------------------
 
     def init_magics(self):
         from IPython.core import magics as m
         self.magics_manager = magic.MagicsManager(shell=self,
                                    parent=self,
                                    user_magics=m.UserMagics(self))
         self.configurables.append(self.magics_manager)
 
         # Expose as public API from the magics manager
         self.register_magics = self.magics_manager.register
 
         self.register_magics(m.AutoMagics, m.BasicMagics, m.CodeMagics,
             m.ConfigMagics, m.DisplayMagics, m.ExecutionMagics,
             m.ExtensionMagics, m.HistoryMagics, m.LoggingMagics,
             m.NamespaceMagics, m.OSMagics, m.PylabMagics, m.ScriptMagics,
         )
 
         # Register Magic Aliases
         mman = self.magics_manager
         # FIXME: magic aliases should be defined by the Magics classes
         # or in MagicsManager, not here
         mman.register_alias('ed', 'edit')
         mman.register_alias('hist', 'history')
         mman.register_alias('rep', 'recall')
         mman.register_alias('SVG', 'svg', 'cell')
         mman.register_alias('HTML', 'html', 'cell')
         mman.register_alias('file', 'writefile', 'cell')
 
         # FIXME: Move the color initialization to the DisplayHook, which
         # should be split into a prompt manager and displayhook. We probably
         # even need a centralize colors management object.
         self.magic('colors %s' % self.colors)
     
     # Defined here so that it's included in the documentation
     @functools.wraps(magic.MagicsManager.register_function)
     def register_magic_function(self, func, magic_kind='line', magic_name=None):
         self.magics_manager.register_function(func, 
                                   magic_kind=magic_kind, magic_name=magic_name)
 
     def run_line_magic(self, magic_name, line):
         """Execute the given line magic.
 
         Parameters
         ----------
         magic_name : str
           Name of the desired magic function, without '%' prefix.
 
         line : str
           The rest of the input line as a single string.
         """
         fn = self.find_line_magic(magic_name)
         if fn is None:
             cm = self.find_cell_magic(magic_name)
             etpl = "Line magic function `%%%s` not found%s."
             extra = '' if cm is None else (' (But cell magic `%%%%%s` exists, '
                                     'did you mean that instead?)' % magic_name )
             error(etpl % (magic_name, extra))
         else:
             # Note: this is the distance in the stack to the user's frame.
             # This will need to be updated if the internal calling logic gets
             # refactored, or else we'll be expanding the wrong variables.
             stack_depth = 2
             magic_arg_s = self.var_expand(line, stack_depth)
             # Put magic args in a list so we can call with f(*a) syntax
             args = [magic_arg_s]
             kwargs = {}
             # Grab local namespace if we need it:
             if getattr(fn, "needs_local_scope", False):
                 kwargs['local_ns'] = sys._getframe(stack_depth).f_locals
             with self.builtin_trap:
                 result = fn(*args,**kwargs)
             return result
 
     def run_cell_magic(self, magic_name, line, cell):
         """Execute the given cell magic.
         
         Parameters
         ----------
         magic_name : str
           Name of the desired magic function, without '%' prefix.
 
         line : str
           The rest of the first input line as a single string.
 
         cell : str
           The body of the cell as a (possibly multiline) string.
         """
         fn = self.find_cell_magic(magic_name)
         if fn is None:
             lm = self.find_line_magic(magic_name)
             etpl = "Cell magic `%%{0}` not found{1}."
             extra = '' if lm is None else (' (But line magic `%{0}` exists, '
                             'did you mean that instead?)'.format(magic_name))
             error(etpl.format(magic_name, extra))
         elif cell == '':
             message = '%%{0} is a cell magic, but the cell body is empty.'.format(magic_name)
             if self.find_line_magic(magic_name) is not None:
                 message += ' Did you mean the line magic %{0} (single %)?'.format(magic_name)
             raise UsageError(message)
         else:
             # Note: this is the distance in the stack to the user's frame.
             # This will need to be updated if the internal calling logic gets
             # refactored, or else we'll be expanding the wrong variables.
             stack_depth = 2
             magic_arg_s = self.var_expand(line, stack_depth)
             with self.builtin_trap:
                 result = fn(magic_arg_s, cell)
             return result
 
     def find_line_magic(self, magic_name):
         """Find and return a line magic by name.
 
         Returns None if the magic isn't found."""
         return self.magics_manager.magics['line'].get(magic_name)
 
     def find_cell_magic(self, magic_name):
         """Find and return a cell magic by name.
 
         Returns None if the magic isn't found."""
         return self.magics_manager.magics['cell'].get(magic_name)
 
     def find_magic(self, magic_name, magic_kind='line'):
         """Find and return a magic of the given type by name.
 
         Returns None if the magic isn't found."""
         return self.magics_manager.magics[magic_kind].get(magic_name)
 
     def magic(self, arg_s):
         """DEPRECATED. Use run_line_magic() instead.
 
         Call a magic function by name.
 
         Input: a string containing the name of the magic function to call and
         any additional arguments to be passed to the magic.
 
         magic('name -opt foo bar') is equivalent to typing at the ipython
         prompt:
 
         In[1]: %name -opt foo bar
 
         To call a magic without arguments, simply use magic('name').
 
         This provides a proper Python function to call IPython's magics in any
         valid Python code you can type at the interpreter, including loops and
         compound statements.
         """
         # TODO: should we issue a loud deprecation warning here?
         magic_name, _, magic_arg_s = arg_s.partition(' ')
         magic_name = magic_name.lstrip(prefilter.ESC_MAGIC)
         return self.run_line_magic(magic_name, magic_arg_s)
 
     #-------------------------------------------------------------------------
     # Things related to macros
     #-------------------------------------------------------------------------
 
     def define_macro(self, name, themacro):
         """Define a new macro
 
         Parameters
         ----------
         name : str
             The name of the macro.
         themacro : str or Macro
             The action to do upon invoking the macro.  If a string, a new
             Macro object is created by passing the string to it.
         """
 
         from IPython.core import macro
 
         if isinstance(themacro, string_types):
             themacro = macro.Macro(themacro)
         if not isinstance(themacro, macro.Macro):
             raise ValueError('A macro must be a string or a Macro instance.')
         self.user_ns[name] = themacro
 
     #-------------------------------------------------------------------------
     # Things related to the running of system commands
     #-------------------------------------------------------------------------
 
     def system_piped(self, cmd):
         """Call the given cmd in a subprocess, piping stdout/err
 
         Parameters
         ----------
         cmd : str
           Command to execute (can not end in '&', as background processes are
           not supported.  Should not be a command that expects input
           other than simple text.
         """
         if cmd.rstrip().endswith('&'):
             # this is *far* from a rigorous test
             # We do not support backgrounding processes because we either use
             # pexpect or pipes to read from.  Users can always just call
             # os.system() or use ip.system=ip.system_raw
             # if they really want a background process.
             raise OSError("Background processes not supported.")
 
         # we explicitly do NOT return the subprocess status code, because
         # a non-None value would trigger :func:`sys.displayhook` calls.
         # Instead, we store the exit_code in user_ns.
         self.user_ns['_exit_code'] = system(self.var_expand(cmd, depth=1))
 
     def system_raw(self, cmd):
         """Call the given cmd in a subprocess using os.system on Windows or
         subprocess.call using the system shell on other platforms.
 
         Parameters
         ----------
         cmd : str
           Command to execute.
         """
         cmd = self.var_expand(cmd, depth=1)
         # protect os.system from UNC paths on Windows, which it can't handle:
         if sys.platform == 'win32':
             from IPython.utils._process_win32 import AvoidUNCPath
             with AvoidUNCPath() as path:
                 if path is not None:
                     cmd = '"pushd %s &&"%s' % (path, cmd)
                 cmd = py3compat.unicode_to_str(cmd)
                 try:
                     ec = os.system(cmd)
                 except KeyboardInterrupt:
                     print('\n' + self.get_exception_only(), file=sys.stderr)
                     ec = -2
         else:
             cmd = py3compat.unicode_to_str(cmd)
             # For posix the result of the subprocess.call() below is an exit
             # code, which by convention is zero for success, positive for
             # program failure.  Exit codes above 128 are reserved for signals,
             # and the formula for converting a signal to an exit code is usually
             # signal_number+128.  To more easily differentiate between exit
             # codes and signals, ipython uses negative numbers.  For instance
             # since control-c is signal 2 but exit code 130, ipython's
             # _exit_code variable will read -2.  Note that some shells like
             # csh and fish don't follow sh/bash conventions for exit codes.
             executable = os.environ.get('SHELL', None)
             try:
                 # Use env shell instead of default /bin/sh
                 ec = subprocess.call(cmd, shell=True, executable=executable)
             except KeyboardInterrupt:
                 # intercept control-C; a long traceback is not useful here
                 print('\n' + self.get_exception_only(), file=sys.stderr)
                 ec = 130
             if ec > 128:
                 ec = -(ec - 128)
         
         # We explicitly do NOT return the subprocess status code, because
         # a non-None value would trigger :func:`sys.displayhook` calls.
         # Instead, we store the exit_code in user_ns.  Note the semantics
         # of _exit_code: for control-c, _exit_code == -signal.SIGNIT,
         # but raising SystemExit(_exit_code) will give status 254!
         self.user_ns['_exit_code'] = ec
 
     # use piped system by default, because it is better behaved
     system = system_piped
 
     def getoutput(self, cmd, split=True, depth=0):
         """Get output (possibly including stderr) from a subprocess.
 
         Parameters
         ----------
         cmd : str
           Command to execute (can not end in '&', as background processes are
           not supported.
         split : bool, optional
           If True, split the output into an IPython SList.  Otherwise, an
           IPython LSString is returned.  These are objects similar to normal
           lists and strings, with a few convenience attributes for easier
           manipulation of line-based output.  You can use '?' on them for
           details.
         depth : int, optional
           How many frames above the caller are the local variables which should
           be expanded in the command string? The default (0) assumes that the
           expansion variables are in the stack frame calling this function.
         """
         if cmd.rstrip().endswith('&'):
             # this is *far* from a rigorous test
             raise OSError("Background processes not supported.")
         out = getoutput(self.var_expand(cmd, depth=depth+1))
         if split:
             out = SList(out.splitlines())
         else:
             out = LSString(out)
         return out
 
     #-------------------------------------------------------------------------
     # Things related to aliases
     #-------------------------------------------------------------------------
 
     def init_alias(self):
         self.alias_manager = AliasManager(shell=self, parent=self)
         self.configurables.append(self.alias_manager)
 
     #-------------------------------------------------------------------------
     # Things related to extensions
     #-------------------------------------------------------------------------
 
     def init_extension_manager(self):
         self.extension_manager = ExtensionManager(shell=self, parent=self)
         self.configurables.append(self.extension_manager)
 
     #-------------------------------------------------------------------------
     # Things related to payloads
     #-------------------------------------------------------------------------
 
     def init_payload(self):
         self.payload_manager = PayloadManager(parent=self)
         self.configurables.append(self.payload_manager)
     
     #-------------------------------------------------------------------------
     # Things related to the prefilter
     #-------------------------------------------------------------------------
 
     def init_prefilter(self):
         self.prefilter_manager = PrefilterManager(shell=self, parent=self)
         self.configurables.append(self.prefilter_manager)
         # Ultimately this will be refactored in the new interpreter code, but
         # for now, we should expose the main prefilter method (there's legacy
         # code out there that may rely on this).
         self.prefilter = self.prefilter_manager.prefilter_lines
 
     def auto_rewrite_input(self, cmd):
         """Print to the screen the rewritten form of the user's command.
 
         This shows visual feedback by rewriting input lines that cause
         automatic calling to kick in, like::
 
           /f x
 
         into::
 
           ------> f(x)
 
         after the user's input prompt.  This helps the user understand that the
         input line was transformed automatically by IPython.
         """
         if not self.show_rewritten_input:
             return
 
         # This is overridden in TerminalInteractiveShell to use fancy prompts
         print("------> " + cmd)
 
     #-------------------------------------------------------------------------
     # Things related to extracting values/expressions from kernel and user_ns
     #-------------------------------------------------------------------------
 
     def _user_obj_error(self):
         """return simple exception dict
         
         for use in user_expressions
         """
         
         etype, evalue, tb = self._get_exc_info()
         stb = self.InteractiveTB.get_exception_only(etype, evalue)
         
         exc_info = {
             u'status' : 'error',
             u'traceback' : stb,
             u'ename' : unicode_type(etype.__name__),
             u'evalue' : py3compat.safe_unicode(evalue),
         }
 
         return exc_info
     
     def _format_user_obj(self, obj):
         """format a user object to display dict
         
         for use in user_expressions
         """
         
         data, md = self.display_formatter.format(obj)
         value = {
             'status' : 'ok',
             'data' : data,
             'metadata' : md,
         }
         return value
     
     def user_expressions(self, expressions):
         """Evaluate a dict of expressions in the user's namespace.
 
         Parameters
         ----------
         expressions : dict
           A dict with string keys and string values.  The expression values
           should be valid Python expressions, each of which will be evaluated
           in the user namespace.
 
         Returns
         -------
         A dict, keyed like the input expressions dict, with the rich mime-typed
         display_data of each value.
         """
         out = {}
         user_ns = self.user_ns
         global_ns = self.user_global_ns
         
         for key, expr in iteritems(expressions):
             try:
                 value = self._format_user_obj(eval(expr, global_ns, user_ns))
             except:
                 value = self._user_obj_error()
             out[key] = value
         return out
 
     #-------------------------------------------------------------------------
     # Things related to the running of code
     #-------------------------------------------------------------------------
 
     def ex(self, cmd):
         """Execute a normal python statement in user namespace."""
         with self.builtin_trap:
             exec(cmd, self.user_global_ns, self.user_ns)
 
     def ev(self, expr):
         """Evaluate python expression expr in user namespace.
 
         Returns the result of evaluation
         """
         with self.builtin_trap:
             return eval(expr, self.user_global_ns, self.user_ns)
 
     def safe_execfile(self, fname, *where, **kw):
         """A safe version of the builtin execfile().
 
         This version will never throw an exception, but instead print
         helpful error messages to the screen.  This only works on pure
         Python files with the .py extension.
 
         Parameters
         ----------
         fname : string
             The name of the file to be executed.
         where : tuple
             One or two namespaces, passed to execfile() as (globals,locals).
             If only one is given, it is passed as both.
         exit_ignore : bool (False)
             If True, then silence SystemExit for non-zero status (it is always
             silenced for zero status, as it is so common).
         raise_exceptions : bool (False)
             If True raise exceptions everywhere. Meant for testing.
         shell_futures : bool (False)
             If True, the code will share future statements with the interactive
             shell. It will both be affected by previous __future__ imports, and
             any __future__ imports in the code will affect the shell. If False,
             __future__ imports are not shared in either direction.
 
         """
         kw.setdefault('exit_ignore', False)
         kw.setdefault('raise_exceptions', False)
         kw.setdefault('shell_futures', False)
 
         fname = os.path.abspath(os.path.expanduser(fname))
 
         # Make sure we can open the file
         try:
             with open(fname):
                 pass
         except:
             warn('Could not open file <%s> for safe execution.' % fname)
             return
 
         # Find things also in current directory.  This is needed to mimic the
         # behavior of running a script from the system command line, where
         # Python inserts the script's directory into sys.path
         dname = os.path.dirname(fname)
 
         with prepended_to_syspath(dname):
             try:
                 glob, loc = (where + (None, ))[:2]
                 py3compat.execfile(
                     fname, glob, loc,
                     self.compile if kw['shell_futures'] else None)
             except SystemExit as status:
                 # If the call was made with 0 or None exit status (sys.exit(0)
                 # or sys.exit() ), don't bother showing a traceback, as both of
                 # these are considered normal by the OS:
                 # > python -c'import sys;sys.exit(0)'; echo $?
                 # 0
                 # > python -c'import sys;sys.exit()'; echo $?
                 # 0
                 # For other exit status, we show the exception unless
                 # explicitly silenced, but only in short form.
                 if status.code:
                     if kw['raise_exceptions']:
                         raise
                     if not kw['exit_ignore']:
                         self.showtraceback(exception_only=True)
             except:
                 if kw['raise_exceptions']:
                     raise
                 # tb offset is 2 because we wrap execfile
                 self.showtraceback(tb_offset=2)
 
     def safe_execfile_ipy(self, fname, shell_futures=False, raise_exceptions=False):
         """Like safe_execfile, but for .ipy or .ipynb files with IPython syntax.
 
         Parameters
         ----------
         fname : str
             The name of the file to execute.  The filename must have a
             .ipy or .ipynb extension.
         shell_futures : bool (False)
             If True, the code will share future statements with the interactive
             shell. It will both be affected by previous __future__ imports, and
             any __future__ imports in the code will affect the shell. If False,
             __future__ imports are not shared in either direction.
         raise_exceptions : bool (False)
             If True raise exceptions everywhere.  Meant for testing.
         """
         fname = os.path.abspath(os.path.expanduser(fname))
 
         # Make sure we can open the file
         try:
             with open(fname):
                 pass
         except:
             warn('Could not open file <%s> for safe execution.' % fname)
             return
 
         # Find things also in current directory.  This is needed to mimic the
         # behavior of running a script from the system command line, where
         # Python inserts the script's directory into sys.path
         dname = os.path.dirname(fname)
         
         def get_cells():
             """generator for sequence of code blocks to run"""
             if fname.endswith('.ipynb'):
                 from nbformat import read
                 with io_open(fname) as f:
                     nb = read(f, as_version=4)
                     if not nb.cells:
                         return
                     for cell in nb.cells:
                         if cell.cell_type == 'code':
                             yield cell.source
             else:
                 with open(fname) as f:
                     yield f.read()
 
         with prepended_to_syspath(dname):
             try:
                 for cell in get_cells():
                     result = self.run_cell(cell, silent=True, shell_futures=shell_futures)
                     if raise_exceptions:
                         result.raise_error()
                     elif not result.success:
                         break
             except:
                 if raise_exceptions:
                     raise
                 self.showtraceback()
                 warn('Unknown failure executing file: <%s>' % fname)
 
     def safe_run_module(self, mod_name, where):
         """A safe version of runpy.run_module().
 
         This version will never throw an exception, but instead print
         helpful error messages to the screen.
 
         `SystemExit` exceptions with status code 0 or None are ignored.
 
         Parameters
         ----------
         mod_name : string
             The name of the module to be executed.
         where : dict
             The globals namespace.
         """
         try:
             try:
                 where.update(
                     runpy.run_module(str(mod_name), run_name="__main__",
                                      alter_sys=True)
                     )
             except SystemExit as status:
                 if status.code:
                     raise
         except:
             self.showtraceback()
             warn('Unknown failure executing module: <%s>' % mod_name)
 
     def run_cell(self, raw_cell, store_history=False, silent=False, shell_futures=True):
         """Run a complete IPython cell.
 
         Parameters
         ----------
         raw_cell : str
           The code (including IPython code such as %magic functions) to run.
         store_history : bool
           If True, the raw and translated cell will be stored in IPython's
           history. For user code calling back into IPython's machinery, this
           should be set to False.
         silent : bool
           If True, avoid side-effects, such as implicit displayhooks and
           and logging.  silent=True forces store_history=False.
         shell_futures : bool
           If True, the code will share future statements with the interactive
           shell. It will both be affected by previous __future__ imports, and
           any __future__ imports in the code will affect the shell. If False,
           __future__ imports are not shared in either direction.
 
         Returns
         -------
         result : :class:`ExecutionResult`
         """
         result = ExecutionResult()
 
         if (not raw_cell) or raw_cell.isspace():
             return result
         
         if silent:
             store_history = False
 
         if store_history:
             result.execution_count = self.execution_count
 
         def error_before_exec(value):
             result.error_before_exec = value
             return result
 
         self.events.trigger('pre_execute')
         if not silent:
             self.events.trigger('pre_run_cell')
 
         # If any of our input transformation (input_transformer_manager or
         # prefilter_manager) raises an exception, we store it in this variable
         # so that we can display the error after logging the input and storing
         # it in the history.
         preprocessing_exc_tuple = None
         try:
             # Static input transformations
             cell = self.input_transformer_manager.transform_cell(raw_cell)
         except SyntaxError:
             preprocessing_exc_tuple = sys.exc_info()
             cell = raw_cell  # cell has to exist so it can be stored/logged
         else:
             if len(cell.splitlines()) == 1:
                 # Dynamic transformations - only applied for single line commands
                 with self.builtin_trap:
                     try:
                         # use prefilter_lines to handle trailing newlines
                         # restore trailing newline for ast.parse
                         cell = self.prefilter_manager.prefilter_lines(cell) + '\n'
                     except Exception:
                         # don't allow prefilter errors to crash IPython
                         preprocessing_exc_tuple = sys.exc_info()
 
         # Store raw and processed history
         if store_history:
             self.history_manager.store_inputs(self.execution_count,
                                               cell, raw_cell)
         if not silent:
             self.logger.log(cell, raw_cell)
 
         # Display the exception if input processing failed.
         if preprocessing_exc_tuple is not None:
             self.showtraceback(preprocessing_exc_tuple)
             if store_history:
                 self.execution_count += 1
             return error_before_exec(preprocessing_exc_tuple[2])
 
         # Our own compiler remembers the __future__ environment. If we want to
         # run code with a separate __future__ environment, use the default
         # compiler
         compiler = self.compile if shell_futures else CachingCompiler()
 
         with self.builtin_trap:
             cell_name = self.compile.cache(cell, self.execution_count)
 
             with self.display_trap:
                 # Compile to bytecode
                 try:
                     code_ast = compiler.ast_parse(cell, filename=cell_name)
                 except self.custom_exceptions as e:
                     etype, value, tb = sys.exc_info()
                     self.CustomTB(etype, value, tb)
                     return error_before_exec(e)
                 except IndentationError as e:
                     self.showindentationerror()
                     if store_history:
                         self.execution_count += 1
                     return error_before_exec(e)
                 except (OverflowError, SyntaxError, ValueError, TypeError,
                         MemoryError) as e:
                     self.showsyntaxerror()
                     if store_history:
                         self.execution_count += 1
                     return error_before_exec(e)
 
                 # Apply AST transformations
                 try:
                     code_ast = self.transform_ast(code_ast)
                 except InputRejected as e:
                     self.showtraceback()
                     if store_history:
                         self.execution_count += 1
                     return error_before_exec(e)
 
                 # Give the displayhook a reference to our ExecutionResult so it
                 # can fill in the output value.
                 self.displayhook.exec_result = result
 
                 # Execute the user code
                 interactivity = "none" if silent else self.ast_node_interactivity
                 self.run_ast_nodes(code_ast.body, cell_name,
                    interactivity=interactivity, compiler=compiler, result=result)
 
                 # Reset this so later displayed values do not modify the
                 # ExecutionResult
                 self.displayhook.exec_result = None
 
                 self.events.trigger('post_execute')
                 if not silent:
                     self.events.trigger('post_run_cell')
 
         if store_history:
             # Write output to the database. Does nothing unless
             # history output logging is enabled.
             self.history_manager.store_output(self.execution_count)
             # Each cell is a *single* input, regardless of how many lines it has
             self.execution_count += 1
 
         return result
     
     def transform_ast(self, node):
         """Apply the AST transformations from self.ast_transformers
         
         Parameters
         ----------
         node : ast.Node
           The root node to be transformed. Typically called with the ast.Module
           produced by parsing user input.
         
         Returns
         -------
         An ast.Node corresponding to the node it was called with. Note that it
         may also modify the passed object, so don't rely on references to the
         original AST.
         """
         for transformer in self.ast_transformers:
             try:
                 node = transformer.visit(node)
             except InputRejected:
                 # User-supplied AST transformers can reject an input by raising
                 # an InputRejected.  Short-circuit in this case so that we
                 # don't unregister the transform.
                 raise
             except Exception:
                 warn("AST transformer %r threw an error. It will be unregistered." % transformer)
                 self.ast_transformers.remove(transformer)
         
         if self.ast_transformers:
             ast.fix_missing_locations(node)
         return node
                 
 
     def run_ast_nodes(self, nodelist, cell_name, interactivity='last_expr',
                         compiler=compile, result=None):
         """Run a sequence of AST nodes. The execution mode depends on the
         interactivity parameter.
 
         Parameters
         ----------
         nodelist : list
           A sequence of AST nodes to run.
         cell_name : str
           Will be passed to the compiler as the filename of the cell. Typically
           the value returned by ip.compile.cache(cell).
         interactivity : str
           'all', 'last', 'last_expr' or 'none', specifying which nodes should be
           run interactively (displaying output from expressions). 'last_expr'
           will run the last node interactively only if it is an expression (i.e.
           expressions in loops or other blocks are not displayed. Other values
           for this parameter will raise a ValueError.
         compiler : callable
           A function with the same interface as the built-in compile(), to turn
           the AST nodes into code objects. Default is the built-in compile().
         result : ExecutionResult, optional
           An object to store exceptions that occur during execution.
 
         Returns
         -------
         True if an exception occurred while running code, False if it finished
         running.
         """
         if not nodelist:
             return
 
         if interactivity == 'last_expr':
             if isinstance(nodelist[-1], ast.Expr):
                 interactivity = "last"
             else:
                 interactivity = "none"
 
         if interactivity == 'none':
             to_run_exec, to_run_interactive = nodelist, []
         elif interactivity == 'last':
             to_run_exec, to_run_interactive = nodelist[:-1], nodelist[-1:]
         elif interactivity == 'all':
             to_run_exec, to_run_interactive = [], nodelist
         else:
             raise ValueError("Interactivity was %r" % interactivity)
 
         try:
             for i, node in enumerate(to_run_exec):
                 mod = ast.Module([node])
                 code = compiler(mod, cell_name, "exec")
                 if self.run_code(code, result):
                     return True
 
             for i, node in enumerate(to_run_interactive):
                 mod = ast.Interactive([node])
                 code = compiler(mod, cell_name, "single")
                 if self.run_code(code, result):
                     return True
 
             # Flush softspace
             if softspace(sys.stdout, 0):
                 print()
 
         except:
             # It's possible to have exceptions raised here, typically by
             # compilation of odd code (such as a naked 'return' outside a
             # function) that did parse but isn't valid. Typically the exception
             # is a SyntaxError, but it's safest just to catch anything and show
             # the user a traceback.
 
             # We do only one try/except outside the loop to minimize the impact
             # on runtime, and also because if any node in the node list is
             # broken, we should stop execution completely.
             if result:
                 result.error_before_exec = sys.exc_info()[1]
             self.showtraceback()
             return True
 
         return False
 
     def run_code(self, code_obj, result=None):
         """Execute a code object.
 
         When an exception occurs, self.showtraceback() is called to display a
         traceback.
 
         Parameters
         ----------
         code_obj : code object
           A compiled code object, to be executed
         result : ExecutionResult, optional
           An object to store exceptions that occur during execution.
 
         Returns
         -------
         False : successful execution.
         True : an error occurred.
         """
         # Set our own excepthook in case the user code tries to call it
         # directly, so that the IPython crash handler doesn't get triggered
         old_excepthook, sys.excepthook = sys.excepthook, self.excepthook
 
         # we save the original sys.excepthook in the instance, in case config
         # code (such as magics) needs access to it.
         self.sys_excepthook = old_excepthook
         outflag = 1  # happens in more places, so it's easier as default
         try:
             try:
                 self.hooks.pre_run_code_hook()
                 #rprint('Running code', repr(code_obj)) # dbg
                 exec(code_obj, self.user_global_ns, self.user_ns)
             finally:
                 # Reset our crash handler in place
                 sys.excepthook = old_excepthook
         except SystemExit as e:
             if result is not None:
                 result.error_in_exec = e
             self.showtraceback(exception_only=True)
             warn("To exit: use 'exit', 'quit', or Ctrl-D.", level=1)
         except self.custom_exceptions:
             etype, value, tb = sys.exc_info()
             if result is not None:
                 result.error_in_exec = value
             self.CustomTB(etype, value, tb)
         except:
             if result is not None:
                 result.error_in_exec = sys.exc_info()[1]
             self.showtraceback()
         else:
             outflag = 0
         return outflag
 
     # For backwards compatibility
     runcode = run_code
 
     #-------------------------------------------------------------------------
     # Things related to GUI support and pylab
     #-------------------------------------------------------------------------
 
     def enable_gui(self, gui=None):
         raise NotImplementedError('Implement enable_gui in a subclass')
     
     def enable_matplotlib(self, gui=None):
         """Enable interactive matplotlib and inline figure support.
         
         This takes the following steps:
         
         1. select the appropriate eventloop and matplotlib backend
         2. set up matplotlib for interactive use with that backend
         3. configure formatters for inline figure display
         4. enable the selected gui eventloop
         
         Parameters
         ----------
         gui : optional, string
           If given, dictates the choice of matplotlib GUI backend to use
           (should be one of IPython's supported backends, 'qt', 'osx', 'tk',
           'gtk', 'wx' or 'inline'), otherwise we use the default chosen by
           matplotlib (as dictated by the matplotlib build-time options plus the
           user's matplotlibrc configuration file).  Note that not all backends
           make sense in all contexts, for example a terminal ipython can't
           display figures inline.
         """
         from IPython.core import pylabtools as pt
         gui, backend = pt.find_gui_and_backend(gui, self.pylab_gui_select)
     
         if gui != 'inline':
             # If we have our first gui selection, store it
             if self.pylab_gui_select is None:
                 self.pylab_gui_select = gui
             # Otherwise if they are different
             elif gui != self.pylab_gui_select:
                 print ('Warning: Cannot change to a different GUI toolkit: %s.'
                         ' Using %s instead.' % (gui, self.pylab_gui_select))
                 gui, backend = pt.find_gui_and_backend(self.pylab_gui_select)
         
         pt.activate_matplotlib(backend)
         pt.configure_inline_support(self, backend)
         
         # Now we must activate the gui pylab wants to use, and fix %run to take
         # plot updates into account
         self.enable_gui(gui)
         self.magics_manager.registry['ExecutionMagics'].default_runner = \
             pt.mpl_runner(self.safe_execfile)
         
         return gui, backend
 
     def enable_pylab(self, gui=None, import_all=True, welcome_message=False):
         """Activate pylab support at runtime.
 
         This turns on support for matplotlib, preloads into the interactive
         namespace all of numpy and pylab, and configures IPython to correctly
         interact with the GUI event loop.  The GUI backend to be used can be
         optionally selected with the optional ``gui`` argument.
         
         This method only adds preloading the namespace to InteractiveShell.enable_matplotlib.
 
         Parameters
         ----------
         gui : optional, string
           If given, dictates the choice of matplotlib GUI backend to use
           (should be one of IPython's supported backends, 'qt', 'osx', 'tk',
           'gtk', 'wx' or 'inline'), otherwise we use the default chosen by
           matplotlib (as dictated by the matplotlib build-time options plus the
           user's matplotlibrc configuration file).  Note that not all backends
           make sense in all contexts, for example a terminal ipython can't
           display figures inline.
         import_all : optional, bool, default: True
           Whether to do `from numpy import *` and `from pylab import *`
           in addition to module imports.
         welcome_message : deprecated
           This argument is ignored, no welcome message will be displayed.
         """
         from IPython.core.pylabtools import import_pylab
         
         gui, backend = self.enable_matplotlib(gui)
         
         # We want to prevent the loading of pylab to pollute the user's
         # namespace as shown by the %who* magics, so we execute the activation
         # code in an empty namespace, and we update *both* user_ns and
         # user_ns_hidden with this information.
         ns = {}
         import_pylab(ns, import_all)
         # warn about clobbered names
         ignored = {"__builtins__"}
         both = set(ns).intersection(self.user_ns).difference(ignored)
         clobbered = [ name for name in both if self.user_ns[name] is not ns[name] ]
         self.user_ns.update(ns)
         self.user_ns_hidden.update(ns)
         return gui, backend, clobbered
 
     #-------------------------------------------------------------------------
     # Utilities
     #-------------------------------------------------------------------------
 
     def var_expand(self, cmd, depth=0, formatter=DollarFormatter()):
         """Expand python variables in a string.
 
         The depth argument indicates how many frames above the caller should
         be walked to look for the local namespace where to expand variables.
 
         The global namespace for expansion is always the user's interactive
         namespace.
         """
         ns = self.user_ns.copy()
         try:
             frame = sys._getframe(depth+1)
         except ValueError:
             # This is thrown if there aren't that many frames on the stack,
             # e.g. if a script called run_line_magic() directly.
             pass
         else:
             ns.update(frame.f_locals)
 
         try:
             # We have to use .vformat() here, because 'self' is a valid and common
             # name, and expanding **ns for .format() would make it collide with
             # the 'self' argument of the method.
             cmd = formatter.vformat(cmd, args=[], kwargs=ns)
         except Exception:
             # if formatter couldn't format, just let it go untransformed
             pass
         return cmd
 
     def mktempfile(self, data=None, prefix='ipython_edit_'):
         """Make a new tempfile and return its filename.
 
         This makes a call to tempfile.mkstemp (created in a tempfile.mkdtemp),
         but it registers the created filename internally so ipython cleans it up
         at exit time.
 
         Optional inputs:
 
           - data(None): if data is given, it gets written out to the temp file
             immediately, and the file is closed again."""
 
         dirname = tempfile.mkdtemp(prefix=prefix)
         self.tempdirs.append(dirname)
 
         handle, filename = tempfile.mkstemp('.py', prefix, dir=dirname)
         os.close(handle)  # On Windows, there can only be one open handle on a file
         self.tempfiles.append(filename)
 
         if data:
             tmp_file = open(filename,'w')
             tmp_file.write(data)
             tmp_file.close()
         return filename
 
     @undoc
     def write(self,data):
         """DEPRECATED: Write a string to the default output"""
         warn('InteractiveShell.write() is deprecated, use sys.stdout instead',
              DeprecationWarning, stacklevel=2)
         sys.stdout.write(data)
 
     @undoc
     def write_err(self,data):
         """DEPRECATED: Write a string to the default error output"""
         warn('InteractiveShell.write_err() is deprecated, use sys.stderr instead',
              DeprecationWarning, stacklevel=2)
         sys.stderr.write(data)
 
     def ask_yes_no(self, prompt, default=None, interrupt=None):
         if self.quiet:
             return True
         return ask_yes_no(prompt,default,interrupt)
 
     def show_usage(self):
         """Show a usage message"""
         page.page(IPython.core.usage.interactive_usage)
 
     def extract_input_lines(self, range_str, raw=False):
         """Return as a string a set of input history slices.
 
         Parameters
         ----------
         range_str : string
             The set of slices is given as a string, like "~5/6-~4/2 4:8 9",
             since this function is for use by magic functions which get their
             arguments as strings. The number before the / is the session
             number: ~n goes n back from the current session.
 
         raw : bool, optional
             By default, the processed input is used.  If this is true, the raw
             input history is used instead.
 
         Notes
         -----
 
         Slices can be described with two notations:
 
         * ``N:M`` -> standard python form, means including items N...(M-1).
         * ``N-M`` -> include items N..M (closed endpoint).
         """
         lines = self.history_manager.get_range_by_str(range_str, raw=raw)
         return "\n".join(x for _, _, x in lines)
 
     def find_user_code(self, target, raw=True, py_only=False, skip_encoding_cookie=True, search_ns=False):
         """Get a code string from history, file, url, or a string or macro.
 
         This is mainly used by magic functions.
 
         Parameters
         ----------
 
         target : str
 
           A string specifying code to retrieve. This will be tried respectively
           as: ranges of input history (see %history for syntax), url,
           corresponding .py file, filename, or an expression evaluating to a
           string or Macro in the user namespace.
 
         raw : bool
           If true (default), retrieve raw history. Has no effect on the other
           retrieval mechanisms.
 
         py_only : bool (default False)
           Only try to fetch python code, do not try alternative methods to decode file
           if unicode fails.
 
         Returns
         -------
         A string of code.
 
         ValueError is raised if nothing is found, and TypeError if it evaluates
         to an object of another type. In each case, .args[0] is a printable
         message.
         """
         code = self.extract_input_lines(target, raw=raw)  # Grab history
         if code:
             return code
         try:
             if target.startswith(('http://', 'https://')):
                 return openpy.read_py_url(target, skip_encoding_cookie=skip_encoding_cookie)
         except UnicodeDecodeError:
             if not py_only :
                 # Deferred import
                 try:
                     from urllib.request import urlopen  # Py3
                 except ImportError:
                     from urllib import urlopen
                 response = urlopen(target)
                 return response.read().decode('latin1')
             raise ValueError(("'%s' seem to be unreadable.") % target)
 
         potential_target = [target]
         try :
             potential_target.insert(0,get_py_filename(target))
         except IOError:
             pass
 
         for tgt in potential_target :
             if os.path.isfile(tgt):                        # Read file
                 try :
                     return openpy.read_py_file(tgt, skip_encoding_cookie=skip_encoding_cookie)
                 except UnicodeDecodeError :
                     if not py_only :
                         with io_open(tgt,'r', encoding='latin1') as f :
                             return f.read()
                     raise ValueError(("'%s' seem to be unreadable.") % target)
             elif os.path.isdir(os.path.expanduser(tgt)):
                 raise ValueError("'%s' is a directory, not a regular file." % target)
 
         if search_ns:
             # Inspect namespace to load object source
             object_info = self.object_inspect(target, detail_level=1)
             if object_info['found'] and object_info['source']:
                 return object_info['source']
 
         try:                                              # User namespace
             codeobj = eval(target, self.user_ns)
         except Exception:
             raise ValueError(("'%s' was not found in history, as a file, url, "
                                 "nor in the user namespace.") % target)
 
         if isinstance(codeobj, string_types):
             return codeobj
         elif isinstance(codeobj, Macro):
             return codeobj.value
 
         raise TypeError("%s is neither a string nor a macro." % target,
                         codeobj)
 
     #-------------------------------------------------------------------------
     # Things related to IPython exiting
     #-------------------------------------------------------------------------
     def atexit_operations(self):
         """This will be executed at the time of exit.
 
         Cleanup operations and saving of persistent data that is done
         unconditionally by IPython should be performed here.
 
         For things that may depend on startup flags or platform specifics (such
         as having readline or not), register a separate atexit function in the
         code that has the appropriate information, rather than trying to
         clutter
         """
         # Close the history session (this stores the end time and line count)
         # this must be *before* the tempfile cleanup, in case of temporary
         # history db
         self.history_manager.end_session()
 
         # Cleanup all tempfiles and folders left around
         for tfile in self.tempfiles:
             try:
                 os.unlink(tfile)
             except OSError:
                 pass
 
         for tdir in self.tempdirs:
             try:
                 os.rmdir(tdir)
             except OSError:
                 pass
 
         # Clear all user namespaces to release all references cleanly.
         self.reset(new_session=False)
 
         # Run user hooks
         self.hooks.shutdown_hook()
 
     def cleanup(self):
         self.restore_sys_module_state()
 
 
     # Overridden in terminal subclass to change prompts
     def switch_doctest_mode(self, mode):
         pass
 
 
 class InteractiveShellABC(with_metaclass(abc.ABCMeta, object)):
     """An abstract base class for InteractiveShell."""
 
 InteractiveShellABC.register(InteractiveShell)

IPython/core/magics/config.py

@@ -1,160 +1,159 b''
 """Implementation of configuration-related magic functions.
 """
 from __future__ import print_function
 from __future__ import absolute_import
 #-----------------------------------------------------------------------------
 #  Copyright (c) 2012 The IPython Development Team.
 #
 #  Distributed under the terms of the Modified BSD License.
 #
 #  The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Stdlib
 import re
 
 # Our own packages
 from IPython.core.error import UsageError
 from IPython.core.magic import Magics, magics_class, line_magic
 from logging import error
 
 #-----------------------------------------------------------------------------
 # Magic implementation classes
 #-----------------------------------------------------------------------------
 
 reg = re.compile('^\w+\.\w+$')
 @magics_class
 class ConfigMagics(Magics):
 
     def __init__(self, shell):
         super(ConfigMagics, self).__init__(shell)
         self.configurables = []
 
     @line_magic
     def config(self, s):
         """configure IPython
 
             %config Class[.trait=value]
 
         This magic exposes most of the IPython config system. Any
         Configurable class should be able to be configured with the simple
         line::
 
             %config Class.trait=value
 
         Where `value` will be resolved in the user's namespace, if it is an
         expression or variable name.
 
         Examples
         --------
 
         To see what classes are available for config, pass no arguments::
 
             In [1]: %config
             Available objects for config:
                 TerminalInteractiveShell
                 HistoryManager
                 PrefilterManager
                 AliasManager
                 IPCompleter
-                PromptManager
                 DisplayFormatter
 
         To view what is configurable on a given class, just pass the class
         name::
 
             In [2]: %config IPCompleter
             IPCompleter options
             -----------------
             IPCompleter.omit__names=<Enum>
                 Current: 2
                 Choices: (0, 1, 2)
                 Instruct the completer to omit private method names
                 Specifically, when completing on ``object.<tab>``.
                 When 2 [default]: all names that start with '_' will be excluded.
                 When 1: all 'magic' names (``__foo__``) will be excluded.
                 When 0: nothing will be excluded.
             IPCompleter.merge_completions=<CBool>
                 Current: True
                 Whether to merge completion results into a single list
                 If False, only the completion results from the first non-empty
                 completer will be returned.
             IPCompleter.limit_to__all__=<CBool>
                 Current: False
                 Instruct the completer to use __all__ for the completion
                 Specifically, when completing on ``object.<tab>``.
                 When True: only those names in obj.__all__ will be included.
                 When False [default]: the __all__ attribute is ignored
             IPCompleter.greedy=<CBool>
                 Current: False
                 Activate greedy completion
                 This will enable completion on elements of lists, results of
                 function calls, etc., but can be unsafe because the code is
                 actually evaluated on TAB.
 
         but the real use is in setting values::
 
             In [3]: %config IPCompleter.greedy = True
 
         and these values are read from the user_ns if they are variables::
 
             In [4]: feeling_greedy=False
 
             In [5]: %config IPCompleter.greedy = feeling_greedy
 
         """
         from traitlets.config.loader import Config
         # some IPython objects are Configurable, but do not yet have
         # any configurable traits.  Exclude them from the effects of
         # this magic, as their presence is just noise:
         configurables = [ c for c in self.shell.configurables
                           if c.__class__.class_traits(config=True) ]
         classnames = [ c.__class__.__name__ for c in configurables ]
 
         line = s.strip()
         if not line:
             # print available configurable names
             print("Available objects for config:")
             for name in classnames:
                 print("    ", name)
             return
         elif line in classnames:
             # `%config TerminalInteractiveShell` will print trait info for
             # TerminalInteractiveShell
             c = configurables[classnames.index(line)]
             cls = c.__class__
             help = cls.class_get_help(c)
             # strip leading '--' from cl-args:
             help = re.sub(re.compile(r'^--', re.MULTILINE), '', help)
             print(help)
             return
         elif reg.match(line):
             cls, attr = line.split('.')
             return getattr(configurables[classnames.index(cls)],attr)
         elif '=' not in line:
             msg = "Invalid config statement: %r, "\
                   "should be `Class.trait = value`."
             
             ll = line.lower()
             for classname in classnames:
                 if ll == classname.lower():
                     msg = msg + '\nDid you mean %s (note the case)?' % classname
                     break
 
             raise UsageError( msg % line)
 
         # otherwise, assume we are setting configurables.
         # leave quotes on args when splitting, because we want
         # unquoted args to eval in user_ns
         cfg = Config()
         exec("cfg."+line, locals(), self.shell.user_ns)
 
         for configurable in configurables:
             try:
                 configurable.update_config(cfg)
             except Exception as e:
                 error(e)

IPython/lib/lexers.py

@@ -1,509 +1,512 b''
 # -*- coding: utf-8 -*-
 """
 Defines a variety of Pygments lexers for highlighting IPython code.
 
 This includes:
 
     IPythonLexer, IPython3Lexer
         Lexers for pure IPython (python + magic/shell commands)
 
     IPythonPartialTracebackLexer, IPythonTracebackLexer
         Supports 2.x and 3.x via keyword `python3`.  The partial traceback
         lexer reads everything but the Python code appearing in a traceback.
         The full lexer combines the partial lexer with an IPython lexer.
 
     IPythonConsoleLexer
         A lexer for IPython console sessions, with support for tracebacks.
 
     IPyLexer
         A friendly lexer which examines the first line of text and from it,
         decides whether to use an IPython lexer or an IPython console lexer.
         This is probably the only lexer that needs to be explicitly added
         to Pygments.
 
 """
 #-----------------------------------------------------------------------------
 # Copyright (c) 2013, the IPython Development Team.
 #
 # Distributed under the terms of the Modified BSD License.
 #
 # The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 # Standard library
 import re
 
 # Third party
 from pygments.lexers import BashLexer, PythonLexer, Python3Lexer
 from pygments.lexer import (
     Lexer, DelegatingLexer, RegexLexer, do_insertions, bygroups, using,
 )
 from pygments.token import (
     Generic, Keyword, Literal, Name, Operator, Other, Text, Error,
 )
 from pygments.util import get_bool_opt
 
 # Local
 
 line_re = re.compile('.*?\n')
 
 __all__ = ['build_ipy_lexer', 'IPython3Lexer', 'IPythonLexer',
            'IPythonPartialTracebackLexer', 'IPythonTracebackLexer',
            'IPythonConsoleLexer', 'IPyLexer']
 
 ipython_tokens = [
   (r"(?s)(\s*)(%%)(\w+)(.*)", bygroups(Text, Operator, Keyword, Text)),
   (r'(?s)(^\s*)(%%!)([^\n]*\n)(.*)', bygroups(Text, Operator, Text, using(BashLexer))),
   (r"(%%?)(\w+)(\?\??)$",  bygroups(Operator, Keyword, Operator)),
   (r"\b(\?\??)(\s*)$",  bygroups(Operator, Text)),
   (r'(%)(sx|sc|system)(.*)(\n)', bygroups(Operator, Keyword,
                                        using(BashLexer), Text)),
   (r'(%)(\w+)(.*\n)', bygroups(Operator, Keyword, Text)),
   (r'^(!!)(.+)(\n)', bygroups(Operator, using(BashLexer), Text)),
   (r'(!)(?!=)(.+)(\n)', bygroups(Operator, using(BashLexer), Text)),
   (r'^(\s*)(\?\??)(\s*%{0,2}[\w\.\*]*)', bygroups(Text, Operator, Text)),
   (r'(\s*%{0,2}[\w\.\*]*)(\?\??)(\s*)$', bygroups(Text, Operator, Text)),
 ]
 
 def build_ipy_lexer(python3):
     """Builds IPython lexers depending on the value of `python3`.
 
     The lexer inherits from an appropriate Python lexer and then adds
     information about IPython specific keywords (i.e. magic commands,
     shell commands, etc.)
 
     Parameters
     ----------
     python3 : bool
         If `True`, then build an IPython lexer from a Python 3 lexer.
 
     """
     # It would be nice to have a single IPython lexer class which takes
     # a boolean `python3`.  But since there are two Python lexer classes,
     # we will also have two IPython lexer classes.
     if python3:
         PyLexer = Python3Lexer
         name = 'IPython3'
         aliases = ['ipython3']
         doc = """IPython3 Lexer"""
     else:
         PyLexer = PythonLexer
         name = 'IPython'
         aliases = ['ipython2', 'ipython']
         doc = """IPython Lexer"""
 
     tokens = PyLexer.tokens.copy()
     tokens['root'] = ipython_tokens + tokens['root']
 
     attrs = {'name': name, 'aliases': aliases, 'filenames': [],
              '__doc__': doc, 'tokens': tokens}
 
     return type(name, (PyLexer,), attrs)
 
 
 IPython3Lexer = build_ipy_lexer(python3=True)
 IPythonLexer = build_ipy_lexer(python3=False)
 
 
 class IPythonPartialTracebackLexer(RegexLexer):
     """
     Partial lexer for IPython tracebacks.
 
     Handles all the non-python output. This works for both Python 2.x and 3.x.
 
     """
     name = 'IPython Partial Traceback'
 
     tokens = {
         'root': [
             # Tracebacks for syntax errors have a different style.
             # For both types of tracebacks, we mark the first line with
             # Generic.Traceback.  For syntax errors, we mark the filename
             # as we mark the filenames for non-syntax tracebacks.
             #
             # These two regexps define how IPythonConsoleLexer finds a
             # traceback.
             #
             ## Non-syntax traceback
             (r'^(\^C)?(-+\n)', bygroups(Error, Generic.Traceback)),
             ## Syntax traceback
             (r'^(  File)(.*)(, line )(\d+\n)',
              bygroups(Generic.Traceback, Name.Namespace,
                       Generic.Traceback, Literal.Number.Integer)),
 
             # (Exception Identifier)(Whitespace)(Traceback Message)
             (r'(?u)(^[^\d\W]\w*)(\s*)(Traceback.*?\n)',
              bygroups(Name.Exception, Generic.Whitespace, Text)),
             # (Module/Filename)(Text)(Callee)(Function Signature)
             # Better options for callee and function signature?
             (r'(.*)( in )(.*)(\(.*\)\n)',
              bygroups(Name.Namespace, Text, Name.Entity, Name.Tag)),
             # Regular line: (Whitespace)(Line Number)(Python Code)
             (r'(\s*?)(\d+)(.*?\n)',
              bygroups(Generic.Whitespace, Literal.Number.Integer, Other)),
             # Emphasized line: (Arrow)(Line Number)(Python Code)
             # Using Exception token so arrow color matches the Exception.
             (r'(-*>?\s?)(\d+)(.*?\n)',
              bygroups(Name.Exception, Literal.Number.Integer, Other)),
             # (Exception Identifier)(Message)
             (r'(?u)(^[^\d\W]\w*)(:.*?\n)',
              bygroups(Name.Exception, Text)),
             # Tag everything else as Other, will be handled later.
             (r'.*\n', Other),
         ],
     }
 
 
 class IPythonTracebackLexer(DelegatingLexer):
     """
     IPython traceback lexer.
 
     For doctests, the tracebacks can be snipped as much as desired with the
     exception to the lines that designate a traceback. For non-syntax error
     tracebacks, this is the line of hyphens. For syntax error tracebacks,
     this is the line which lists the File and line number.
 
     """
     # The lexer inherits from DelegatingLexer.  The "root" lexer is an
     # appropriate IPython lexer, which depends on the value of the boolean
     # `python3`.  First, we parse with the partial IPython traceback lexer.
     # Then, any code marked with the "Other" token is delegated to the root
     # lexer.
     #
     name = 'IPython Traceback'
     aliases = ['ipythontb']
 
     def __init__(self, **options):
         self.python3 = get_bool_opt(options, 'python3', False)
         if self.python3:
             self.aliases = ['ipython3tb']
         else:
             self.aliases = ['ipython2tb', 'ipythontb']
 
         if self.python3:
             IPyLexer = IPython3Lexer
         else:
             IPyLexer = IPythonLexer
 
         DelegatingLexer.__init__(self, IPyLexer,
                                  IPythonPartialTracebackLexer, **options)
 
 class IPythonConsoleLexer(Lexer):
     """
     An IPython console lexer for IPython code-blocks and doctests, such as:
 
     .. code-block:: rst
 
         .. code-block:: ipythonconsole
 
             In [1]: a = 'foo'
 
             In [2]: a
             Out[2]: 'foo'
 
             In [3]: print a
             foo
 
             In [4]: 1 / 0
 
 
     Support is also provided for IPython exceptions:
 
     .. code-block:: rst
 
         .. code-block:: ipythonconsole
 
             In [1]: raise Exception
 
             ---------------------------------------------------------------------------
             Exception                                 Traceback (most recent call last)
             <ipython-input-1-fca2ab0ca76b> in <module>()
             ----> 1 raise Exception
 
             Exception:
 
     """
     name = 'IPython console session'
     aliases = ['ipythonconsole']
     mimetypes = ['text/x-ipython-console']
 
     # The regexps used to determine what is input and what is output.
     # The default prompts for IPython are:
     #
-    #     c.PromptManager.in_template  = 'In [\#]: '
-    #     c.PromptManager.in2_template = '   .\D.: '
-    #     c.PromptManager.out_template = 'Out[\#]: '
+    #    in           = 'In [#]: '
+    #    continuation = '   .D.: '
+    #    template     = 'Out[#]: '
+    #
+    # Where '#' is the 'prompt number' or 'execution count' and 'D' 
+    # D is a number of dots  matching the width of the execution count 
     #
     in1_regex = r'In \[[0-9]+\]: '
     in2_regex = r'   \.\.+\.: '
     out_regex = r'Out\[[0-9]+\]: '
 
     #: The regex to determine when a traceback starts.
     ipytb_start = re.compile(r'^(\^C)?(-+\n)|^(  File)(.*)(, line )(\d+\n)')
 
     def __init__(self, **options):
         """Initialize the IPython console lexer.
 
         Parameters
         ----------
         python3 : bool
             If `True`, then the console inputs are parsed using a Python 3
             lexer. Otherwise, they are parsed using a Python 2 lexer.
         in1_regex : RegexObject
             The compiled regular expression used to detect the start
             of inputs. Although the IPython configuration setting may have a
             trailing whitespace, do not include it in the regex. If `None`,
             then the default input prompt is assumed.
         in2_regex : RegexObject
             The compiled regular expression used to detect the continuation
             of inputs. Although the IPython configuration setting may have a
             trailing whitespace, do not include it in the regex. If `None`,
             then the default input prompt is assumed.
         out_regex : RegexObject
             The compiled regular expression used to detect outputs. If `None`,
             then the default output prompt is assumed.
 
         """
         self.python3 = get_bool_opt(options, 'python3', False)
         if self.python3:
             self.aliases = ['ipython3console']
         else:
             self.aliases = ['ipython2console', 'ipythonconsole']
 
         in1_regex = options.get('in1_regex', self.in1_regex)
         in2_regex = options.get('in2_regex', self.in2_regex)
         out_regex = options.get('out_regex', self.out_regex)
 
         # So that we can work with input and output prompts which have been
         # rstrip'd (possibly by editors) we also need rstrip'd variants. If
         # we do not do this, then such prompts will be tagged as 'output'.
         # The reason can't just use the rstrip'd variants instead is because
         # we want any whitespace associated with the prompt to be inserted
         # with the token. This allows formatted code to be modified so as hide
         # the appearance of prompts, with the whitespace included. One example
         # use of this is in copybutton.js from the standard lib Python docs.
         in1_regex_rstrip = in1_regex.rstrip() + '\n'
         in2_regex_rstrip = in2_regex.rstrip() + '\n'
         out_regex_rstrip = out_regex.rstrip() + '\n'
 
         # Compile and save them all.
         attrs = ['in1_regex', 'in2_regex', 'out_regex',
                  'in1_regex_rstrip', 'in2_regex_rstrip', 'out_regex_rstrip']
         for attr in attrs:
             self.__setattr__(attr, re.compile(locals()[attr]))
 
         Lexer.__init__(self, **options)
 
         if self.python3:
             pylexer = IPython3Lexer
             tblexer = IPythonTracebackLexer
         else:
             pylexer = IPythonLexer
             tblexer = IPythonTracebackLexer
 
         self.pylexer = pylexer(**options)
         self.tblexer = tblexer(**options)
 
         self.reset()
 
     def reset(self):
         self.mode = 'output'
         self.index = 0
         self.buffer = u''
         self.insertions = []
 
     def buffered_tokens(self):
         """
         Generator of unprocessed tokens after doing insertions and before
         changing to a new state.
 
         """
         if self.mode == 'output':
             tokens = [(0, Generic.Output, self.buffer)]
         elif self.mode == 'input':
             tokens = self.pylexer.get_tokens_unprocessed(self.buffer)
         else: # traceback
             tokens = self.tblexer.get_tokens_unprocessed(self.buffer)
 
         for i, t, v in do_insertions(self.insertions, tokens):
             # All token indexes are relative to the buffer.
             yield self.index + i, t, v
 
         # Clear it all
         self.index += len(self.buffer)
         self.buffer = u''
         self.insertions = []
 
     def get_mci(self, line):
         """
         Parses the line and returns a 3-tuple: (mode, code, insertion).
 
         `mode` is the next mode (or state) of the lexer, and is always equal
         to 'input', 'output', or 'tb'.
 
         `code` is a portion of the line that should be added to the buffer
         corresponding to the next mode and eventually lexed by another lexer.
         For example, `code` could be Python code if `mode` were 'input'.
 
         `insertion` is a 3-tuple (index, token, text) representing an
         unprocessed "token" that will be inserted into the stream of tokens
         that are created from the buffer once we change modes. This is usually
         the input or output prompt.
 
         In general, the next mode depends on current mode and on the contents
         of `line`.
 
         """
         # To reduce the number of regex match checks, we have multiple
         # 'if' blocks instead of 'if-elif' blocks.
 
         # Check for possible end of input
         in2_match = self.in2_regex.match(line)
         in2_match_rstrip = self.in2_regex_rstrip.match(line)
         if (in2_match and in2_match.group().rstrip() == line.rstrip()) or \
            in2_match_rstrip:
             end_input = True
         else:
             end_input = False
         if end_input and self.mode != 'tb':
             # Only look for an end of input when not in tb mode.
             # An ellipsis could appear within the traceback.
             mode = 'output'
             code = u''
             insertion = (0, Generic.Prompt, line)
             return mode, code, insertion
 
         # Check for output prompt
         out_match = self.out_regex.match(line)
         out_match_rstrip = self.out_regex_rstrip.match(line)
         if out_match or out_match_rstrip:
             mode = 'output'
             if out_match:
                 idx = out_match.end()
             else:
                 idx = out_match_rstrip.end()
             code = line[idx:]
             # Use the 'heading' token for output.  We cannot use Generic.Error
             # since it would conflict with exceptions.
             insertion = (0, Generic.Heading, line[:idx])
             return mode, code, insertion
 
 
         # Check for input or continuation prompt (non stripped version)
         in1_match = self.in1_regex.match(line)
         if in1_match or (in2_match and self.mode != 'tb'):
             # New input or when not in tb, continued input.
             # We do not check for continued input when in tb since it is
             # allowable to replace a long stack with an ellipsis.
             mode = 'input'
             if in1_match:
                 idx = in1_match.end()
             else: # in2_match
                 idx = in2_match.end()
             code = line[idx:]
             insertion = (0, Generic.Prompt, line[:idx])
             return mode, code, insertion
 
         # Check for input or continuation prompt (stripped version)
         in1_match_rstrip = self.in1_regex_rstrip.match(line)
         if in1_match_rstrip or (in2_match_rstrip and self.mode != 'tb'):
             # New input or when not in tb, continued input.
             # We do not check for continued input when in tb since it is
             # allowable to replace a long stack with an ellipsis.
             mode = 'input'
             if in1_match_rstrip:
                 idx = in1_match_rstrip.end()
             else: # in2_match
                 idx = in2_match_rstrip.end()
             code = line[idx:]
             insertion = (0, Generic.Prompt, line[:idx])
             return mode, code, insertion
 
         # Check for traceback
         if self.ipytb_start.match(line):
             mode = 'tb'
             code = line
             insertion = None
             return mode, code, insertion
 
         # All other stuff...
         if self.mode in ('input', 'output'):
             # We assume all other text is output. Multiline input that
             # does not use the continuation marker cannot be detected.
             # For example, the 3 in the following is clearly output:
             #
             #    In [1]: print 3
             #    3
             #
             # But the following second line is part of the input:
             #
             #    In [2]: while True:
             #        print True
             #
             # In both cases, the 2nd line will be 'output'.
             #
             mode = 'output'
         else:
             mode = 'tb'
 
         code = line
         insertion = None
 
         return mode, code, insertion
 
     def get_tokens_unprocessed(self, text):
         self.reset()
         for match in line_re.finditer(text):
             line = match.group()
             mode, code, insertion = self.get_mci(line)
 
             if mode != self.mode:
                 # Yield buffered tokens before transitioning to new mode.
                 for token in self.buffered_tokens():
                     yield token
                 self.mode = mode
 
             if insertion:
                 self.insertions.append((len(self.buffer), [insertion]))
             self.buffer += code
 
         for token in self.buffered_tokens():
             yield token
 
 class IPyLexer(Lexer):
     """
     Primary lexer for all IPython-like code.
 
     This is a simple helper lexer.  If the first line of the text begins with
     "In \[[0-9]+\]:", then the entire text is parsed with an IPython console
     lexer. If not, then the entire text is parsed with an IPython lexer.
 
     The goal is to reduce the number of lexers that are registered
     with Pygments.
 
     """
     name = 'IPy session'
     aliases = ['ipy']
 
     def __init__(self, **options):
         self.python3 = get_bool_opt(options, 'python3', False)
         if self.python3:
             self.aliases = ['ipy3']
         else:
             self.aliases = ['ipy2', 'ipy']
 
         Lexer.__init__(self, **options)
 
         self.IPythonLexer = IPythonLexer(**options)
         self.IPythonConsoleLexer = IPythonConsoleLexer(**options)
 
     def get_tokens_unprocessed(self, text):
         # Search for the input prompt anywhere...this allows code blocks to
         # begin with comments as well.
         if re.match(r'.*(In \[[0-9]+\]:)', text.strip(), re.DOTALL):
             lex = self.IPythonConsoleLexer
         else:
             lex = self.IPythonLexer
         for token in lex.get_tokens_unprocessed(text):
             yield token
 

IPython/terminal/ipapp.py

@@ -1,374 +1,372 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 The :class:`~IPython.core.application.Application` object for the command
 line :command:`ipython` program.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 from __future__ import absolute_import
 from __future__ import print_function
 
 import logging
 import os
 import sys
 import warnings
 
 from traitlets.config.loader import Config
 from traitlets.config.application import boolean_flag, catch_config_error, Application
 from IPython.core import release
 from IPython.core import usage
 from IPython.core.completer import IPCompleter
 from IPython.core.crashhandler import CrashHandler
 from IPython.core.formatters import PlainTextFormatter
 from IPython.core.history import HistoryManager
 from IPython.core.application import (
     ProfileDir, BaseIPythonApplication, base_flags, base_aliases
 )
 from IPython.core.magics import ScriptMagics
 from IPython.core.shellapp import (
     InteractiveShellApp, shell_flags, shell_aliases
 )
 from IPython.extensions.storemagic import StoreMagics
 from .ptshell import TerminalInteractiveShell
 from IPython.paths import get_ipython_dir
 from traitlets import (
     Bool, List, Dict, default, observe,
 )
 
 #-----------------------------------------------------------------------------
 # Globals, utilities and helpers
 #-----------------------------------------------------------------------------
 
 _examples = """
 ipython --matplotlib       # enable matplotlib integration
 ipython --matplotlib=qt    # enable matplotlib integration with qt4 backend
 
 ipython --log-level=DEBUG  # set logging to DEBUG
 ipython --profile=foo      # start with profile foo
 
 ipython profile create foo # create profile foo w/ default config files
 ipython help profile       # show the help for the profile subcmd
 
 ipython locate             # print the path to the IPython directory
 ipython locate profile foo # print the path to the directory for profile `foo`
 """
 
 #-----------------------------------------------------------------------------
 # Crash handler for this application
 #-----------------------------------------------------------------------------
 
 class IPAppCrashHandler(CrashHandler):
     """sys.excepthook for IPython itself, leaves a detailed report on disk."""
 
     def __init__(self, app):
         contact_name = release.author
         contact_email = release.author_email
         bug_tracker = 'https://github.com/ipython/ipython/issues'
         super(IPAppCrashHandler,self).__init__(
             app, contact_name, contact_email, bug_tracker
         )
 
     def make_report(self,traceback):
         """Return a string containing a crash report."""
 
         sec_sep = self.section_sep
         # Start with parent report
         report = [super(IPAppCrashHandler, self).make_report(traceback)]
         # Add interactive-specific info we may have
         rpt_add = report.append
         try:
             rpt_add(sec_sep+"History of session input:")
             for line in self.app.shell.user_ns['_ih']:
                 rpt_add(line)
             rpt_add('\n*** Last line of input (may not be in above history):\n')
             rpt_add(self.app.shell._last_input_line+'\n')
         except:
             pass
 
         return ''.join(report)
 
 #-----------------------------------------------------------------------------
 # Aliases and Flags
 #-----------------------------------------------------------------------------
 flags = dict(base_flags)
 flags.update(shell_flags)
 frontend_flags = {}
 addflag = lambda *args: frontend_flags.update(boolean_flag(*args))
 addflag('autoedit-syntax', 'TerminalInteractiveShell.autoedit_syntax',
         'Turn on auto editing of files with syntax errors.',
         'Turn off auto editing of files with syntax errors.'
 )
 addflag('simple-prompt', 'TerminalInteractiveShell.simple_prompt',
         "Force simple minimal prompt using `raw_input`",
         "Use a rich interactive prompt with prompt_toolkit",
 )
 
 addflag('banner', 'TerminalIPythonApp.display_banner',
         "Display a banner upon starting IPython.",
         "Don't display a banner upon starting IPython."
 )
 addflag('confirm-exit', 'TerminalInteractiveShell.confirm_exit',
     """Set to confirm when you try to exit IPython with an EOF (Control-D
     in Unix, Control-Z/Enter in Windows). By typing 'exit' or 'quit',
     you can force a direct exit without any confirmation.""",
     "Don't prompt the user when exiting."
 )
 addflag('term-title', 'TerminalInteractiveShell.term_title',
     "Enable auto setting the terminal title.",
     "Disable auto setting the terminal title."
 )
 classic_config = Config()
 classic_config.InteractiveShell.cache_size = 0
 classic_config.PlainTextFormatter.pprint = False
-classic_config.PromptManager.in_template = '>>> '
-classic_config.PromptManager.in2_template = '... '
-classic_config.PromptManager.out_template = ''
+classic_config.TerminalInteractiveShell.prompts_class='IPython.terminal.prompts.ClassicPrompts'
 classic_config.InteractiveShell.separate_in = ''
 classic_config.InteractiveShell.separate_out = ''
 classic_config.InteractiveShell.separate_out2 = ''
 classic_config.InteractiveShell.colors = 'NoColor'
 classic_config.InteractiveShell.xmode = 'Plain'
 
 frontend_flags['classic']=(
     classic_config,
     "Gives IPython a similar feel to the classic Python prompt."
 )
 # # log doesn't make so much sense this way anymore
 # paa('--log','-l',
 #     action='store_true', dest='InteractiveShell.logstart',
 #     help="Start logging to the default log file (./ipython_log.py).")
 #
 # # quick is harder to implement
 frontend_flags['quick']=(
     {'TerminalIPythonApp' : {'quick' : True}},
     "Enable quick startup with no config files."
 )
 
 frontend_flags['i'] = (
     {'TerminalIPythonApp' : {'force_interact' : True}},
     """If running code from the command line, become interactive afterwards.
     It is often useful to follow this with `--` to treat remaining flags as
     script arguments.
     """
 )
 flags.update(frontend_flags)
 
 aliases = dict(base_aliases)
 aliases.update(shell_aliases)
 
 #-----------------------------------------------------------------------------
 # Main classes and functions
 #-----------------------------------------------------------------------------
 
 
 class LocateIPythonApp(BaseIPythonApplication):
     description = """print the path to the IPython dir"""
     subcommands = Dict(dict(
         profile=('IPython.core.profileapp.ProfileLocate',
             "print the path to an IPython profile directory",
         ),
     ))
     def start(self):
         if self.subapp is not None:
             return self.subapp.start()
         else:
             print(self.ipython_dir)
 
 
 class TerminalIPythonApp(BaseIPythonApplication, InteractiveShellApp):
     name = u'ipython'
     description = usage.cl_usage
     crash_handler_class = IPAppCrashHandler
     examples = _examples
 
     flags = Dict(flags)
     aliases = Dict(aliases)
     classes = List()
     @default('classes')
     def _classes_default(self):
         """This has to be in a method, for TerminalIPythonApp to be available."""
         return [
             InteractiveShellApp, # ShellApp comes before TerminalApp, because
             self.__class__,      # it will also affect subclasses (e.g. QtConsole)
             TerminalInteractiveShell,
             HistoryManager,
             ProfileDir,
             PlainTextFormatter,
             IPCompleter,
             ScriptMagics,
             StoreMagics,
         ]
 
     deprecated_subcommands = dict(
         qtconsole=('qtconsole.qtconsoleapp.JupyterQtConsoleApp',
             """DEPRECATED, Will be removed in IPython 6.0 : Launch the Jupyter Qt Console."""
         ),
         notebook=('notebook.notebookapp.NotebookApp',
             """DEPRECATED, Will be removed in IPython 6.0 : Launch the Jupyter HTML Notebook Server."""
         ),
         console=('jupyter_console.app.ZMQTerminalIPythonApp',
             """DEPRECATED, Will be removed in IPython 6.0 : Launch the Jupyter terminal-based Console."""
         ),
         nbconvert=('nbconvert.nbconvertapp.NbConvertApp',
             "DEPRECATED, Will be removed in IPython 6.0 : Convert notebooks to/from other formats."
         ),
         trust=('nbformat.sign.TrustNotebookApp',
             "DEPRECATED, Will be removed in IPython 6.0 : Sign notebooks to trust their potentially unsafe contents at load."
         ),
         kernelspec=('jupyter_client.kernelspecapp.KernelSpecApp',
             "DEPRECATED, Will be removed in IPython 6.0 : Manage Jupyter kernel specifications."
         ),
     )
     subcommands = dict(
         profile = ("IPython.core.profileapp.ProfileApp",
             "Create and manage IPython profiles."
         ),
         kernel = ("ipykernel.kernelapp.IPKernelApp",
             "Start a kernel without an attached frontend."
         ),
         locate=('IPython.terminal.ipapp.LocateIPythonApp',
             LocateIPythonApp.description
         ),
         history=('IPython.core.historyapp.HistoryApp',
             "Manage the IPython history database."
         ),
     )
     deprecated_subcommands['install-nbextension'] = (
         "notebook.nbextensions.InstallNBExtensionApp",
         "DEPRECATED, Will be removed in IPython 6.0 : Install Jupyter notebook extension files"
     )
     subcommands.update(deprecated_subcommands)
 
     # *do* autocreate requested profile, but don't create the config file.
     auto_create=Bool(True)
     # configurables
     quick = Bool(False,
         help="""Start IPython quickly by skipping the loading of config files."""
     ).tag(config=True)
     @observe('quick')
     def _quick_changed(self, change):
         if change['new']:
             self.load_config_file = lambda *a, **kw: None
 
     display_banner = Bool(True,
         help="Whether to display a banner upon starting IPython."
     ).tag(config=True)
 
     # if there is code of files to run from the cmd line, don't interact
     # unless the --i flag (App.force_interact) is true.
     force_interact = Bool(False,
         help="""If a command or file is given via the command-line,
         e.g. 'ipython foo.py', start an interactive shell after executing the
         file or command."""
     ).tag(config=True)
     @observe('force_interact')
     def _force_interact_changed(self, change):
         if change['new']:
             self.interact = True
 
     @observe('file_to_run', 'code_to_run', 'module_to_run')
     def _file_to_run_changed(self, change):
         new = change['new']
         if new:
             self.something_to_run = True
         if new and not self.force_interact:
                 self.interact = False
 
     # internal, not-configurable
     something_to_run=Bool(False)
 
     def parse_command_line(self, argv=None):
         """override to allow old '-pylab' flag with deprecation warning"""
 
         argv = sys.argv[1:] if argv is None else argv
 
         if '-pylab' in argv:
             # deprecated `-pylab` given,
             # warn and transform into current syntax
             argv = argv[:] # copy, don't clobber
             idx = argv.index('-pylab')
             warnings.warn("`-pylab` flag has been deprecated.\n"
             "    Use `--matplotlib <backend>` and import pylab manually.")
             argv[idx] = '--pylab'
 
         return super(TerminalIPythonApp, self).parse_command_line(argv)
     
     @catch_config_error
     def initialize(self, argv=None):
         """Do actions after construct, but before starting the app."""
         super(TerminalIPythonApp, self).initialize(argv)
         if self.subapp is not None:
             # don't bother initializing further, starting subapp
             return
         # print self.extra_args
         if self.extra_args and not self.something_to_run:
             self.file_to_run = self.extra_args[0]
         self.init_path()
         # create the shell
         self.init_shell()
         # and draw the banner
         self.init_banner()
         # Now a variety of things that happen after the banner is printed.
         self.init_gui_pylab()
         self.init_extensions()
         self.init_code()
 
     def init_shell(self):
         """initialize the InteractiveShell instance"""
         # Create an InteractiveShell instance.
         # shell.display_banner should always be False for the terminal
         # based app, because we call shell.show_banner() by hand below
         # so the banner shows *before* all extension loading stuff.
         self.shell = TerminalInteractiveShell.instance(parent=self,
                         profile_dir=self.profile_dir,
                         ipython_dir=self.ipython_dir, user_ns=self.user_ns)
         self.shell.configurables.append(self)
 
     def init_banner(self):
         """optionally display the banner"""
         if self.display_banner and self.interact:
             self.shell.show_banner()
         # Make sure there is a space below the banner.
         if self.log_level <= logging.INFO: print()
 
     def _pylab_changed(self, name, old, new):
         """Replace --pylab='inline' with --pylab='auto'"""
         if new == 'inline':
             warnings.warn("'inline' not available as pylab backend, "
                       "using 'auto' instead.")
             self.pylab = 'auto'
 
     def start(self):
         if self.subapp is not None:
             return self.subapp.start()
         # perform any prexec steps:
         if self.interact:
             self.log.debug("Starting IPython's mainloop...")
             self.shell.mainloop()
         else:
             self.log.debug("IPython not interactive...")
 
 def load_default_config(ipython_dir=None):
     """Load the default config file from the default ipython_dir.
 
     This is useful for embedded shells.
     """
     if ipython_dir is None:
         ipython_dir = get_ipython_dir()
 
     profile_dir = os.path.join(ipython_dir, 'profile_default')
 
     config = Config()
     for cf in Application._load_config_files("ipython_config", path=profile_dir):
         config.update(cf)
 
     return config
 
 launch_new_instance = TerminalIPythonApp.launch_instance
 
 
 if __name__ == '__main__':
     launch_new_instance()

IPython/terminal/ptshell.py

@@ -1,492 +1,494 b''
 """IPython terminal interface using prompt_toolkit in place of readline"""
 from __future__ import print_function
 
 import os
 import sys
 import signal
 from warnings import warn
 
 from IPython.core.error import TryNext
 from IPython.core.interactiveshell import InteractiveShell, InteractiveShellABC
 from IPython.utils.py3compat import PY3, cast_unicode_py2, input
 from IPython.utils.terminal import toggle_set_term_title, set_term_title
 from IPython.utils.process import abbrev_cwd
-from traitlets import Bool, Unicode, Dict, Integer, observe, Instance
+from traitlets import Bool, Unicode, Dict, Integer, observe, Instance, Type
 
 from prompt_toolkit.enums import DEFAULT_BUFFER, SEARCH_BUFFER, EditingMode
 from prompt_toolkit.filters import HasFocus, HasSelection, Condition, ViInsertMode, EmacsInsertMode, IsDone
 from prompt_toolkit.history import InMemoryHistory
 from prompt_toolkit.shortcuts import create_prompt_application, create_eventloop, create_prompt_layout
 from prompt_toolkit.interface import CommandLineInterface
 from prompt_toolkit.key_binding.manager import KeyBindingManager
 from prompt_toolkit.keys import Keys
 from prompt_toolkit.layout.processors import ConditionalProcessor, HighlightMatchingBracketProcessor
 from prompt_toolkit.styles import PygmentsStyle, DynamicStyle
 
 from pygments.styles import get_style_by_name, get_all_styles
 from pygments.token import Token
 
 from .debugger import TerminalPdb, Pdb
 from .magics import TerminalMagics
 from .pt_inputhooks import get_inputhook_func
 from .prompts import Prompts, ClassicPrompts, RichPromptDisplayHook
 from .ptutils import IPythonPTCompleter, IPythonPTLexer
 
 
 def get_default_editor():
     try:
         ed = os.environ['EDITOR']
         if not PY3:
             ed = ed.decode()
         return ed
     except KeyError:
         pass
     except UnicodeError:
         warn("$EDITOR environment variable is not pure ASCII. Using platform "
              "default editor.")
 
     if os.name == 'posix':
         return 'vi'  # the only one guaranteed to be there!
     else:
         return 'notepad' # same in Windows!
 
 _use_simple_prompt = 'IPY_TEST_SIMPLE_PROMPT' in os.environ or not sys.stdin.isatty()
 
 class TerminalInteractiveShell(InteractiveShell):
     colors_force = True
 
     space_for_menu = Integer(6, help='Number of line at the bottom of the screen '
                                                   'to reserve for the completion menu'
                             ).tag(config=True)
 
     def _space_for_menu_changed(self, old, new):
         self._update_layout()
 
     pt_cli = None
     debugger_history = None
 
     simple_prompt = Bool(_use_simple_prompt,
         help="""Use `raw_input` for the REPL, without completion, multiline input, and prompt colors.
 
             Useful when controlling IPython as a subprocess, and piping STDIN/OUT/ERR. Known usage are:
             IPython own testing machinery, and emacs inferior-shell integration through elpy.
 
             This mode default to `True` if the `IPY_TEST_SIMPLE_PROMPT`
             environment variable is set, or the current terminal is not a tty.
 
             """
             ).tag(config=True)
 
     @property
     def debugger_cls(self):
         return Pdb if self.simple_prompt else TerminalPdb
 
     autoedit_syntax = Bool(False,
         help="auto editing of files with syntax errors.",
     ).tag(config=True)
 
 
     confirm_exit = Bool(True,
         help="""
         Set to confirm when you try to exit IPython with an EOF (Control-D
         in Unix, Control-Z/Enter in Windows). By typing 'exit' or 'quit',
         you can force a direct exit without any confirmation.""",
     ).tag(config=True)
 
     editing_mode = Unicode('emacs',
         help="Shortcut style to use at the prompt. 'vi' or 'emacs'.",
     ).tag(config=True)
 
     mouse_support = Bool(False,
         help="Enable mouse support in the prompt"
     ).tag(config=True)
 
     highlighting_style = Unicode('default',
             help="The name of a Pygments style to use for syntax highlighting: \n %s" % ', '.join(get_all_styles())
     ).tag(config=True)
 
     
     @observe('highlighting_style')
     def _highlighting_style_changed(self, change):
         self._style = self._make_style_from_name(self.highlighting_style)
 
     highlighting_style_overrides = Dict(
         help="Override highlighting format for specific tokens"
     ).tag(config=True)
 
     editor = Unicode(get_default_editor(),
         help="Set the editor used by IPython (default to $EDITOR/vi/notepad)."
     ).tag(config=True)
 
+    prompts_class = Type(Prompts, config=True, help='Class used to generate Prompt token for prompt_toolkit')
+
     prompts = Instance(Prompts)
 
     def _prompts_default(self):
-        return Prompts(self)
+        return self.prompts_class(self)
 
     @observe('prompts')
     def _(self, change):
         self._update_layout()
 
     def _displayhook_class_default(self):
         return RichPromptDisplayHook
 
     term_title = Bool(True,
         help="Automatically set the terminal title"
     ).tag(config=True)
 
     display_completions_in_columns = Bool(False,
         help="Display a multi column completion menu.",
     ).tag(config=True)
 
     highlight_matching_brackets = Bool(True,
         help="Highlight matching brackets .",
     ).tag(config=True)
 
     @observe('term_title')
     def init_term_title(self, change=None):
         # Enable or disable the terminal title.
         if self.term_title:
             toggle_set_term_title(True)
             set_term_title('IPython: ' + abbrev_cwd())
         else:
             toggle_set_term_title(False)
 
     def init_prompt_toolkit_cli(self):
         self._app = None
         if self.simple_prompt:
             # Fall back to plain non-interactive output for tests.
             # This is very limited, and only accepts a single line.
             def prompt():
                 return cast_unicode_py2(input('In [%d]: ' % self.execution_count))
             self.prompt_for_code = prompt
             return
 
         kbmanager = KeyBindingManager.for_prompt()
         insert_mode = ViInsertMode() | EmacsInsertMode()
         # Ctrl+J == Enter, seemingly
         @kbmanager.registry.add_binding(Keys.ControlJ,
                             filter=(HasFocus(DEFAULT_BUFFER)
                                     & ~HasSelection()
                                     & insert_mode
                                    ))
         def _(event):
             b = event.current_buffer
             d = b.document
             if not (d.on_last_line or d.cursor_position_row >= d.line_count
                                            - d.empty_line_count_at_the_end()):
                 b.newline()
                 return
 
             status, indent = self.input_splitter.check_complete(d.text)
 
             if (status != 'incomplete') and b.accept_action.is_returnable:
                 b.accept_action.validate_and_handle(event.cli, b)
             else:
                 b.insert_text('\n' + (' ' * (indent or 0)))
 
         @kbmanager.registry.add_binding(Keys.ControlC, filter=HasFocus(DEFAULT_BUFFER))
         def _reset_buffer(event):
             event.current_buffer.reset()
 
         @kbmanager.registry.add_binding(Keys.ControlC, filter=HasFocus(SEARCH_BUFFER))
         def _reset_search_buffer(event):
             if event.current_buffer.document.text:
                 event.current_buffer.reset()
             else:
                 event.cli.push_focus(DEFAULT_BUFFER)
 
         supports_suspend = Condition(lambda cli: hasattr(signal, 'SIGTSTP'))
 
         @kbmanager.registry.add_binding(Keys.ControlZ, filter=supports_suspend)
         def _suspend_to_bg(event):
             event.cli.suspend_to_background()
 
         @Condition
         def cursor_in_leading_ws(cli):
             before = cli.application.buffer.document.current_line_before_cursor
             return (not before) or before.isspace()
 
         # Ctrl+I == Tab
         @kbmanager.registry.add_binding(Keys.ControlI,
                             filter=(HasFocus(DEFAULT_BUFFER)
                                     & ~HasSelection()
                                     & insert_mode
                                     & cursor_in_leading_ws
                                    ))
         def _indent_buffer(event):
             event.current_buffer.insert_text(' ' * 4)
 
         # Pre-populate history from IPython's history database
         history = InMemoryHistory()
         last_cell = u""
         for __, ___, cell in self.history_manager.get_tail(self.history_load_length,
                                                         include_latest=True):
             # Ignore blank lines and consecutive duplicates
             cell = cell.rstrip()
             if cell and (cell != last_cell):
                 history.append(cell)
 
         self._style = self._make_style_from_name(self.highlighting_style)
         style = DynamicStyle(lambda: self._style)
 
         editing_mode = getattr(EditingMode, self.editing_mode.upper())
 
         self._app = create_prompt_application(
                             editing_mode=editing_mode,
                             key_bindings_registry=kbmanager.registry,
                             history=history,
                             completer=IPythonPTCompleter(self.Completer),
                             enable_history_search=True,
                             style=style,
                             mouse_support=self.mouse_support,
                             **self._layout_options()
         )
         self._eventloop = create_eventloop(self.inputhook)
         self.pt_cli = CommandLineInterface(self._app, eventloop=self._eventloop)
 
     def _make_style_from_name(self, name):
         """
         Small wrapper that make an IPython compatible style from a style name
 
         We need that to add style for prompt ... etc. 
         """
         style_cls = get_style_by_name(name)
         style_overrides = {
             Token.Prompt: '#009900',
             Token.PromptNum: '#00ff00 bold',
             Token.OutPrompt: '#990000',
             Token.OutPromptNum: '#ff0000 bold',
         }
         if name == 'default':
             style_cls = get_style_by_name('default')
             # The default theme needs to be visible on both a dark background
             # and a light background, because we can't tell what the terminal
             # looks like. These tweaks to the default theme help with that.
             style_overrides.update({
                 Token.Number: '#007700',
                 Token.Operator: 'noinherit',
                 Token.String: '#BB6622',
                 Token.Name.Function: '#2080D0',
                 Token.Name.Class: 'bold #2080D0',
                 Token.Name.Namespace: 'bold #2080D0',
             })
         style_overrides.update(self.highlighting_style_overrides)
         style = PygmentsStyle.from_defaults(pygments_style_cls=style_cls,
                                             style_dict=style_overrides)
 
         return style
 
     def _layout_options(self):
         """
         Return the current layout option for the current Terminal InteractiveShell
         """
         return {
                 'lexer':IPythonPTLexer(),
                 'reserve_space_for_menu':self.space_for_menu,
                 'get_prompt_tokens':self.prompts.in_prompt_tokens,
                 'get_continuation_tokens':self.prompts.continuation_prompt_tokens,
                 'multiline':True,
                 'display_completions_in_columns': self.display_completions_in_columns,
 
                 # Highlight matching brackets, but only when this setting is
                 # enabled, and only when the DEFAULT_BUFFER has the focus.
                 'extra_input_processors': [ConditionalProcessor(
                         processor=HighlightMatchingBracketProcessor(chars='[](){}'),
                         filter=HasFocus(DEFAULT_BUFFER) & ~IsDone() &
                             Condition(lambda cli: self.highlight_matching_brackets))],
                 }
 
     def _update_layout(self):
         """
         Ask for a re computation of the application layout, if for example ,
         some configuration options have changed.
         """
-        if self._app:
+        if getattr(self, '._app', None):
             self._app.layout = create_prompt_layout(**self._layout_options())
 
     def prompt_for_code(self):
         document = self.pt_cli.run(
             pre_run=self.pre_prompt, reset_current_buffer=True)
         return document.text
 
     def init_io(self):
         if sys.platform not in {'win32', 'cli'}:
             return
 
         import colorama
         colorama.init()
 
         # For some reason we make these wrappers around stdout/stderr.
         # For now, we need to reset them so all output gets coloured.
         # https://github.com/ipython/ipython/issues/8669
         from IPython.utils import io
         io.stdout = io.IOStream(sys.stdout)
         io.stderr = io.IOStream(sys.stderr)
 
     def init_magics(self):
         super(TerminalInteractiveShell, self).init_magics()
         self.register_magics(TerminalMagics)
 
     def init_alias(self):
         # The parent class defines aliases that can be safely used with any
         # frontend.
         super(TerminalInteractiveShell, self).init_alias()
 
         # Now define aliases that only make sense on the terminal, because they
         # need direct access to the console in a way that we can't emulate in
         # GUI or web frontend
         if os.name == 'posix':
             for cmd in ['clear', 'more', 'less', 'man']:
                 self.alias_manager.soft_define_alias(cmd, cmd)
 
 
     def __init__(self, *args, **kwargs):
         super(TerminalInteractiveShell, self).__init__(*args, **kwargs)
         self.init_prompt_toolkit_cli()
         self.init_term_title()
         self.keep_running = True
 
         self.debugger_history = InMemoryHistory()
 
     def ask_exit(self):
         self.keep_running = False
 
     rl_next_input = None
 
     def pre_prompt(self):
         if self.rl_next_input:
             self.pt_cli.application.buffer.text = cast_unicode_py2(self.rl_next_input)
             self.rl_next_input = None
 
     def interact(self):
         while self.keep_running:
             print(self.separate_in, end='')
 
             try:
                 code = self.prompt_for_code()
             except EOFError:
                 if (not self.confirm_exit) \
                         or self.ask_yes_no('Do you really want to exit ([y]/n)?','y','n'):
                     self.ask_exit()
 
             else:
                 if code:
                     self.run_cell(code, store_history=True)
                     if self.autoedit_syntax and self.SyntaxTB.last_syntax_error:
                         self.edit_syntax_error()
 
     def mainloop(self):
         # An extra layer of protection in case someone mashing Ctrl-C breaks
         # out of our internal code.
         while True:
             try:
                 self.interact()
                 break
             except KeyboardInterrupt:
                 print("\nKeyboardInterrupt escaped interact()\n")
         
         if hasattr(self, '_eventloop'):
             self._eventloop.close()
 
     _inputhook = None
     def inputhook(self, context):
         if self._inputhook is not None:
             self._inputhook(context)
 
     def enable_gui(self, gui=None):
         if gui:
             self._inputhook = get_inputhook_func(gui)
         else:
             self._inputhook = None
 
     # Methods to support auto-editing of SyntaxErrors:
 
     def edit_syntax_error(self):
         """The bottom half of the syntax error handler called in the main loop.
 
         Loop until syntax error is fixed or user cancels.
         """
 
         while self.SyntaxTB.last_syntax_error:
             # copy and clear last_syntax_error
             err = self.SyntaxTB.clear_err_state()
             if not self._should_recompile(err):
                 return
             try:
                 # may set last_syntax_error again if a SyntaxError is raised
                 self.safe_execfile(err.filename, self.user_ns)
             except:
                 self.showtraceback()
             else:
                 try:
                     with open(err.filename) as f:
                         # This should be inside a display_trap block and I
                         # think it is.
                         sys.displayhook(f.read())
                 except:
                     self.showtraceback()
 
     def _should_recompile(self, e):
         """Utility routine for edit_syntax_error"""
 
         if e.filename in ('<ipython console>', '<input>', '<string>',
                           '<console>', '<BackgroundJob compilation>',
                           None):
             return False
         try:
             if (self.autoedit_syntax and
                     not self.ask_yes_no(
                         'Return to editor to correct syntax error? '
                         '[Y/n] ', 'y')):
                 return False
         except EOFError:
             return False
 
         def int0(x):
             try:
                 return int(x)
             except TypeError:
                 return 0
 
         # always pass integer line and offset values to editor hook
         try:
             self.hooks.fix_error_editor(e.filename,
                                         int0(e.lineno), int0(e.offset),
                                         e.msg)
         except TryNext:
             warn('Could not open editor')
             return False
         return True
 
     # Run !system commands directly, not through pipes, so terminal programs
     # work correctly.
     system = InteractiveShell.system_raw
 
     def auto_rewrite_input(self, cmd):
         """Overridden from the parent class to use fancy rewriting prompt"""
         if not self.show_rewritten_input:
             return
 
         tokens = self.prompts.rewrite_prompt_tokens()
         if self.pt_cli:
             self.pt_cli.print_tokens(tokens)
             print(cmd)
         else:
             prompt = ''.join(s for t, s in tokens)
             print(prompt, cmd, sep='')
 
     _prompts_before = None
     def switch_doctest_mode(self, mode):
         """Switch prompts to classic for %doctest_mode"""
         if mode:
             self._prompts_before = self.prompts
             self.prompts = ClassicPrompts(self)
         elif self._prompts_before:
             self.prompts = self._prompts_before
             self._prompts_before = None
 
 
 InteractiveShellABC.register(TerminalInteractiveShell)
 
 if __name__ == '__main__':
     TerminalInteractiveShell.instance().interact()

examples/Embedding/embed_class_long.py

@@ -1,135 +1,146 b''
 #!/usr/bin/env python
 """An example of how to embed an IPython shell into a running program.
 
 Please see the documentation in the IPython.Shell module for more details.
 
 The accompanying file embed_class_short.py has quick code fragments for
 embedding which you can cut and paste in your code once you understand how
 things work.
 
 The code in this file is deliberately extra-verbose, meant for learning."""
 from __future__ import print_function
 
 # The basics to get you going:
 
 # IPython injects get_ipython into builtins, so you can know if you have nested
 # copies running.
 
 # Try running this code both at the command line and from inside IPython (with
 # %run example-embed.py)
+
+from IPython.terminal.prompts import Prompts, Token
+
+class CustomPrompt(Prompts):
+
+    def in_prompt_tokens(self, cli=None):
+
+       return [
+            (Token.Prompt, 'In <'),
+            (Token.PromptNum, str(self.shell.execution_count)),
+            (Token.Prompt, '>: '),
+            ]
+
+    def out_prompt_tokens(self):
+       return [
+            (Token.OutPrompt, 'Out<'),
+            (Token.OutPromptNum, str(self.shell.execution_count)),
+            (Token.OutPrompt, '>: '),
+        ]
+ 
+
 from traitlets.config.loader import Config
 try:
     get_ipython
 except NameError:
     nested = 0
     cfg = Config()
-    prompt_config = cfg.PromptManager
-    prompt_config.in_template = 'In <\\#>: '
-    prompt_config.in2_template = '   .\\D.: '
-    prompt_config.out_template = 'Out<\\#>: '
+    cfg.TerminalInteractiveShell.prompts_class=CustomPrompt
 else:
     print("Running nested copies of IPython.")
     print("The prompts for the nested copy have been modified")
     cfg = Config()
     nested = 1
 
 # First import the embeddable shell class
 from IPython.terminal.embed import InteractiveShellEmbed
 
 # Now create an instance of the embeddable shell. The first argument is a
 # string with options exactly as you would type them if you were starting
 # IPython at the system command line. Any parameters you want to define for
 # configuration can thus be specified here.
 ipshell = InteractiveShellEmbed(config=cfg,
                        banner1 = 'Dropping into IPython',
                        exit_msg = 'Leaving Interpreter, back to program.')
 
 # Make a second instance, you can have as many as you want.
-cfg2 = cfg.copy()
-prompt_config = cfg2.PromptManager
-prompt_config.in_template = 'In2<\\#>: '
-if not nested:
-    prompt_config.in_template = 'In2<\\#>: '
-    prompt_config.in2_template = '   .\\D.: '
-    prompt_config.out_template = 'Out<\\#>: '
 ipshell2 = InteractiveShellEmbed(config=cfg,
                         banner1 = 'Second IPython instance.')
 
 print('\nHello. This is printed from the main controller program.\n')
 
 # You can then call ipshell() anywhere you need it (with an optional
 # message):
 ipshell('***Called from top level. '
         'Hit Ctrl-D to exit interpreter and continue program.\n'
         'Note that if you use %kill_embedded, you can fully deactivate\n'
         'This embedded instance so it will never turn on again')
 
 print('\nBack in caller program, moving along...\n')
 
 #---------------------------------------------------------------------------
 # More details:
 
 # InteractiveShellEmbed instances don't print the standard system banner and
 # messages. The IPython banner (which actually may contain initialization
 # messages) is available as get_ipython().banner in case you want it.
 
 # InteractiveShellEmbed instances print the following information everytime they
 # start:
 
 # - A global startup banner.
 
 # - A call-specific header string, which you can use to indicate where in the
 # execution flow the shell is starting.
 
 # They also print an exit message every time they exit.
 
 # Both the startup banner and the exit message default to None, and can be set
 # either at the instance constructor or at any other time with the
 # by setting the banner and exit_msg attributes.
 
 # The shell instance can be also put in 'dummy' mode globally or on a per-call
 # basis. This gives you fine control for debugging without having to change
 # code all over the place.
 
 # The code below illustrates all this.
 
 
 # This is how the global banner and exit_msg can be reset at any point
-ipshell.banner = 'Entering interpreter - New Banner'
+ipshell.banner2 = 'Entering interpreter - New Banner'
 ipshell.exit_msg = 'Leaving interpreter - New exit_msg'
 
 def foo(m):
     s = 'spam'
     ipshell('***In foo(). Try %whos, or print s or m:')
     print('foo says m = ',m)
 
 def bar(n):
     s = 'eggs'
     ipshell('***In bar(). Try %whos, or print s or n:')
     print('bar says n = ',n)
     
 # Some calls to the above functions which will trigger IPython:
 print('Main program calling foo("eggs")\n')
 foo('eggs')
 
 # The shell can be put in 'dummy' mode where calls to it silently return. This
 # allows you, for example, to globally turn off debugging for a program with a
 # single call.
 ipshell.dummy_mode = True
 print('\nTrying to call IPython which is now "dummy":')
 ipshell()
 print('Nothing happened...')
 # The global 'dummy' mode can still be overridden for a single call
 print('\nOverriding dummy mode manually:')
 ipshell(dummy=False)
 
 # Reactivate the IPython shell
 ipshell.dummy_mode = False
 
 print('You can even have multiple embedded instances:')
 ipshell2()
 
 print('\nMain program calling bar("spam")\n')
 bar('spam')
 
 print('Main program finished. Bye!')