Fixes to guiref after more careful proofreading.

IPython/core/usage.py

@@ -1,483 +1,484 b''
 # -*- coding: utf-8 -*-
 """Usage information for the main IPython applications.
 """
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2010  The IPython Development Team
 #  Copyright (C) 2001-2007 Fernando Perez. <[e-mail]>
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 import sys
 from IPython.core import release
 
 cl_usage = """\
 ipython [options] [files]
 
 IPython: an enhanced interactive Python shell.
 
     A Python shell with automatic history (input and output), dynamic object
     introspection, easier configuration, command completion, access to the
     system shell and more.  IPython can also be embedded in running programs.
 
     If invoked with no options, it executes all the files listed in sequence
     and exits, use -i to enter interactive mode after running the files.  Files
     ending in .py will be treated as normal Python, but files ending in .ipy
     can contain special IPython syntax (magic commands, shell expansions, etc.)
 
     Please note that some of the configuration options are not available at the
     command line, simply because they are not practical here. Look into your
     ipython_config.py configuration file for details on those.
 
     This file typically installed in the $HOME/.ipython directory.  For Windows
     users, $HOME resolves to C:\\Documents and Settings\\YourUserName in most
     instances.
 
     In IPython's documentation, we will refer to this directory as IPYTHON_DIR,
     you can change its default location by setting any path you want in this
     environment variable.
 
     For more information, see the manual available in HTML and PDF in your
     installation, or online at http://ipython.scipy.org.
 """
 
 interactive_usage = """
 IPython -- An enhanced Interactive Python
 =========================================
 
 IPython offers a combination of convenient shell features, special commands
 and a history mechanism for both input (command history) and output (results
 caching, similar to Mathematica). It is intended to be a fully compatible
 replacement for the standard Python interpreter, while offering vastly
 improved functionality and flexibility.
 
 At your system command line, type 'ipython -help' to see the command line
 options available. This document only describes interactive features.
 
 Warning: IPython relies on the existence of a global variable called __IP which
 controls the shell itself. If you redefine __IP to anything, bizarre behavior
 will quickly occur.
 
 MAIN FEATURES
 
 * Access to the standard Python help. As of Python 2.1, a help system is
   available with access to object docstrings and the Python manuals. Simply
   type 'help' (no quotes) to access it.
 
 * Magic commands: type %magic for information on the magic subsystem.
 
 * System command aliases, via the %alias command or the ipythonrc config file.
 
 * Dynamic object information:
 
   Typing ?word or word? prints detailed information about an object.  If
   certain strings in the object are too long (docstrings, code, etc.) they get
   snipped in the center for brevity.
 
   Typing ??word or word?? gives access to the full information without
   snipping long strings. Long strings are sent to the screen through the less
   pager if longer than the screen, printed otherwise.
 
   The ?/?? system gives access to the full source code for any object (if
   available), shows function prototypes and other useful information.
 
   If you just want to see an object's docstring, type '%pdoc object' (without
   quotes, and without % if you have automagic on).
 
   Both %pdoc and ?/?? give you access to documentation even on things which are
   not explicitely defined. Try for example typing {}.get? or after import os,
   type os.path.abspath??. The magic functions %pdef, %source and %file operate
   similarly.
 
 * Completion in the local namespace, by typing TAB at the prompt.
 
   At any time, hitting tab will complete any available python commands or
   variable names, and show you a list of the possible completions if there's
   no unambiguous one. It will also complete filenames in the current directory.
 
   This feature requires the readline and rlcomplete modules, so it won't work
   if your Python lacks readline support (such as under Windows).
 
 * Search previous command history in two ways (also requires readline):
 
   - Start typing, and then use Ctrl-p (previous,up) and Ctrl-n (next,down) to
   search through only the history items that match what you've typed so
   far. If you use Ctrl-p/Ctrl-n at a blank prompt, they just behave like
   normal arrow keys.
 
   - Hit Ctrl-r: opens a search prompt. Begin typing and the system searches
   your history for lines that match what you've typed so far, completing as
   much as it can.
 
 * Persistent command history across sessions (readline required).
 
 * Logging of input with the ability to save and restore a working session.
   
 * System escape with !. Typing !ls will run 'ls' in the current directory.
 
 * The reload command does a 'deep' reload of a module: changes made to the
   module since you imported will actually be available without having to exit.
 
 * Verbose and colored exception traceback printouts. See the magic xmode and
   xcolor functions for details (just type %magic).
 
 * Input caching system:
 
   IPython offers numbered prompts (In/Out) with input and output caching. All
   input is saved and can be retrieved as variables (besides the usual arrow
   key recall).
 
   The following GLOBAL variables always exist (so don't overwrite them!):
   _i: stores previous input.
   _ii: next previous.
   _iii: next-next previous.
   _ih : a list of all input _ih[n] is the input from line n.
 
   Additionally, global variables named _i<n> are dynamically created (<n>
   being the prompt counter), such that _i<n> == _ih[<n>]
 
   For example, what you typed at prompt 14 is available as _i14 and _ih[14].
 
   You can create macros which contain multiple input lines from this history,
   for later re-execution, with the %macro function.
 
   The history function %hist allows you to see any part of your input history
   by printing a range of the _i variables. Note that inputs which contain
   magic functions (%) appear in the history with a prepended comment. This is
   because they aren't really valid Python code, so you can't exec them.
 
 * Output caching system:
 
   For output that is returned from actions, a system similar to the input
   cache exists but using _ instead of _i. Only actions that produce a result
   (NOT assignments, for example) are cached. If you are familiar with
   Mathematica, IPython's _ variables behave exactly like Mathematica's %
   variables.
 
   The following GLOBAL variables always exist (so don't overwrite them!):
   _ (one underscore): previous output.
   __ (two underscores): next previous.
   ___ (three underscores): next-next previous.
 
   Global variables named _<n> are dynamically created (<n> being the prompt
   counter), such that the result of output <n> is always available as _<n>.
 
   Finally, a global dictionary named _oh exists with entries for all lines
   which generated output.
 
 * Directory history:
 
   Your history of visited directories is kept in the global list _dh, and the
   magic %cd command can be used to go to any entry in that list.
 
 * Auto-parentheses and auto-quotes (adapted from Nathan Gray's LazyPython)
 
     1. Auto-parentheses
         Callable objects (i.e. functions, methods, etc) can be invoked like
         this (notice the commas between the arguments):
             >>> callable_ob arg1, arg2, arg3
         and the input will be translated to this:
             --> callable_ob(arg1, arg2, arg3)
         You can force auto-parentheses by using '/' as the first character
         of a line.  For example:
             >>> /globals             # becomes 'globals()'
         Note that the '/' MUST be the first character on the line!  This
         won't work:
             >>> print /globals    # syntax error
             
         In most cases the automatic algorithm should work, so you should
         rarely need to explicitly invoke /. One notable exception is if you
         are trying to call a function with a list of tuples as arguments (the
         parenthesis will confuse IPython):
             In [1]: zip (1,2,3),(4,5,6)  # won't work
         but this will work:
             In [2]: /zip (1,2,3),(4,5,6)
             ------> zip ((1,2,3),(4,5,6))
             Out[2]= [(1, 4), (2, 5), (3, 6)]        
 
         IPython tells you that it has altered your command line by
         displaying the new command line preceded by -->.  e.g.:
             In [18]: callable list
             -------> callable (list) 
 
     2. Auto-Quoting
         You can force auto-quoting of a function's arguments by using ',' as
         the first character of a line.  For example:
             >>> ,my_function /home/me   # becomes my_function("/home/me")
 
         If you use ';' instead, the whole argument is quoted as a single
         string (while ',' splits on whitespace):
             >>> ,my_function a b c   # becomes my_function("a","b","c")
             >>> ;my_function a b c   # becomes my_function("a b c")
 
         Note that the ',' MUST be the first character on the line!  This
         won't work:
             >>> x = ,my_function /home/me    # syntax error
 """
 
 interactive_usage_min =  """\
 An enhanced console for Python.
 Some of its features are:
 - Readline support if the readline library is present.
 - Tab completion in the local namespace.
 - Logging of input, see command-line options.
 - System shell escape via ! , eg !ls.
 - Magic commands, starting with a % (like %ls, %pwd, %cd, etc.)
 - Keeps track of locally defined variables via %who, %whos.
 - Show object information with a ? eg ?x or x? (use ?? for more info).
 """
 
 quick_reference = r"""
 IPython -- An enhanced Interactive Python - Quick Reference Card
 ================================================================
 
 obj?, obj??      : Get help, or more help for object (also works as
                    ?obj, ??obj).
 ?foo.*abc*       : List names in 'foo' containing 'abc' in them.
 %magic           : Information about IPython's 'magic' % functions.
 
 Magic functions are prefixed by %, and typically take their arguments without
 parentheses, quotes or even commas for convenience.
  
 Example magic function calls:
 
 %alias d ls -F   : 'd' is now an alias for 'ls -F'
 alias d ls -F    : Works if 'alias' not a python name
 alist = %alias   : Get list of aliases to 'alist'
 cd /usr/share    : Obvious. cd -<tab> to choose from visited dirs.
 %cd??            : See help AND source for magic %cd
 
 System commands:
     
 !cp a.txt b/     : System command escape, calls os.system()
 cp a.txt b/      : after %rehashx, most system commands work without !
 cp ${f}.txt $bar : Variable expansion in magics and system commands
 files = !ls /usr : Capture sytem command output
 files.s, files.l, files.n: "a b c", ['a','b','c'], 'a\nb\nc'
 
 History:
 
 _i, _ii, _iii    : Previous, next previous, next next previous input
 _i4, _ih[2:5]    : Input history line 4, lines 2-4
 exec _i81        : Execute input history line #81 again
 %rep 81          : Edit input history line #81        
 _, __, ___       : previous, next previous, next next previous output
 _dh              : Directory history
 _oh              : Output history
 %hist            : Command history. '%hist -g foo' search history for 'foo'
 
 Autocall:
 
 f 1,2            : f(1,2)
 /f 1,2           : f(1,2) (forced autoparen)
 ,f 1 2           : f("1","2")
 ;f 1 2           : f("1 2")
 
 Remember: TAB completion works in many contexts, not just file names
 or python names.
 
 The following magic functions are currently available:
 
 """
 
 gui_reference = """\
 ===============================
- The IPython graphical console
+ The graphical IPython console
 ===============================
 
-This console is designed to emulate in many aspects the look, feel and workflow
-typical of a terminal environment, but it adds support for a number of
-enhancements that are simply not possible in a real terminal, such as inline
-syntax highlighting, true multiline editing, inline graphics and much more.
+This console is designed to emulate the look, feel and workflow of a terminal
+environment, while adding a number of enhancements that are simply not possible
+in a real terminal, such as inline syntax highlighting, true multiline editing,
+inline graphics and much more.
 
 This quick reference document contains the basic information you'll need to
 know to make the most efficient use of it.  For the various command line
 options available at startup, type ``--help`` at the command line.
 
 
 Multiline editing
 =================
 
 The graphical console is capable of true multiline editing, but it also tries
 to behave intuitively like a terminal when possible.  If you are used to
 IPyhton's old terminal behavior, you should find the transition painless, and
 once you learn a few basic keybindings it will be a much more efficient
 environment.
 
 For single expressions or indented blocks, the console behaves almost like the
 terminal IPython: single expressions are immediately evaluated *if the cursor
 is at the end of the line*, and indented blocks are evaluated once a single
 blank line is entered::
 
     In [1]: print "Hello IPython!"  # Enter was pressed at the end of the line
     Hello IPython!
     
     In [2]: for i in range(10):
        ...: 	print i,
        ...: 	
     0 1 2 3 4 5 6 7 8 9
 
 If you have a single expression and you go back to edit something in the
 beginning, hitting ``Enter`` will split the line (like a text editor) instead
 of executing it.  To execute, you can either go to the end of the line to hit
 ``Enter``, or hit ``Shift-Enter`` anywhere, which is the 'force execution'
 keybinding.
 
 If you want to enter more than one expression in a single input block
 (something not possible in the terminal), you can use ``Control-Enter`` at the
 end of your first line instead of ``Enter``.  At that point the console goes
 into 'cell mode' and even if your inputs are not indented, it will continue
 accepting arbitrarily many lines until either you enter an extra blank line or
 you hit ``Shift-Enter`` (the key binding that forces execution).  When a
 multiline cell is entered, IPython analyzes it and executes its code producing
 an ``Out[n]`` prompt only for the last expression in it, while the rest of the
-cell is executed as if it was a script.  A few examples should clarify this::
+cell is executed as if it was a script.  An example should clarify this::
 
     In [3]: x=1  # Hit C-Enter here
        ...: y=2  # from now on, regular Enter is sufficient
        ...: z=3
        ...: x**2  # This does *not* produce an Out[] value
        ...: x+y+z  # Only the last expression does
        ...: 
     Out[3]: 6
 
 The behavior where an extra blank line forces execution is only active if you
 are actually typing at the keyboard each line, and is meant to make it mimic
 the IPython terminal behavior.  If you paste a long chunk of input (for example
 a long script copied form an editor or web browser), it can contain arbitrarily
-many intermediate blank lines and they won't cause any problems.  You can then
-make it execute by appending a blank line *at the end* or hitting
+many intermediate blank lines and they won't cause any problems.  As always,
+you can then make it execute by appending a blank line *at the end* or hitting
 ``Shift-Enter`` anywhere within the cell.
 
 With the up arrow key, you can retrieve previous blocks of input that contain
-multiple lines.  You can move inside of it like you would in any text editor.
-When you want it executed, the simplest thing to do is to hit the force
-execution key, ``Shift-Enter`` (though you can also navigate to the end and
-append a blank line by using ``Enter`` twice).
+multiple lines.  You can move inside of a multiline cell like you would in any
+text editor.  When you want it executed, the simplest thing to do is to hit the
+force execution key, ``Shift-Enter`` (though you can also navigate to the end
+and append a blank line by using ``Enter`` twice).
 
 If you've edited a multiline cell and accidentally navigate out of it with the
 up or down arrow keys, IPython will clear the cell and replace it with the
 contents of the one above or below that you navigated to.  If this was an
 accident and you want to retrieve the cell you were editing, use the Undo
 keybinding, ``Control-z``.
 
 
 Key bindings
 ============
 
-The IPython console supports most of the basic Emacs line-oriented
-keybindings, in addition to some of its own.
+The IPython console supports most of the basic Emacs line-oriented keybindings,
+in addition to some of its own.
 
 The keybinding prefixes mean:
 
-- C : Control
-- S : Shift
-- M : Meta (typically the Alt key)
+- ``C``: Control
+- ``S``: Shift
+- ``M``: Meta (typically the Alt key)
 
 The keybindings themselves are:
 
-- Enter   : insert new line (may cause execution, see above).
-- C-Enter : force new line, *never* causes execution.
-- S-Enter : *force* execution regardless of where cursor is, no newline added.
-- C-c : copy highlighted text to clipboard (prompts are automatically stripped).
-- C-S-c: copy highlighted text to clipboard (prompts are not stripped).
-- C-v : paste text from clipboard.
-- C-z : undo (retrieves lost text if you move out of a cell with the arrows).
-- C-S-z : redo.
-- C-o : move to 'other' area, between pager and terminal.
-- C-l : clear terminal.
-- C-a : go to beginning of line.
-- C-e : go to end of line.
-- C-k : kill from cursor to the end of the line.
-- C-y : yank (paste)
-- C-p : previous line (like up arrow)
-- C-n : next line (like down arrow)
-- C-f : forward (like right arrow)
-- C-b : back (like left arrow)
-- C-d : delete next character.
-- M-< : move to the beginning of the input region.
-- M-> : move to the end of the input region.
-- M-d : delete next word.
-- M-Backspace : delete previous word.
-- C-. : forced restart of the kernel (a confirmation dialog appears).
+- ``Enter``: insert new line (may cause execution, see above).
+- ``C-Enter``: force new line, *never* causes execution.
+- ``S-Enter``: *force* execution regardless of where cursor is, no newline added.
+- ``C-c``: copy highlighted text to clipboard (prompts are automatically stripped).
+- ``C-S-c``: copy highlighted text to clipboard (prompts are not stripped).
+- ``C-v``: paste text from clipboard.
+- ``C-z``: undo (retrieves lost text if you move out of a cell with the arrows).
+- ``C-S-z``: redo.
+- ``C-o``: move to 'other' area, between pager and terminal.
+- ``C-l``: clear terminal.
+- ``C-a``: go to beginning of line.
+- ``C-e``: go to end of line.
+- ``C-k``: kill from cursor to the end of the line.
+- ``C-y``: yank (paste)
+- ``C-p``: previous line (like up arrow)
+- ``C-n``: next line (like down arrow)
+- ``C-f``: forward (like right arrow)
+- ``C-b``: back (like left arrow)
+- ``C-d``: delete next character.
+- ``M-<``: move to the beginning of the input region.
+- ``M->``: move to the end of the input region.
+- ``M-d``: delete next word.
+- ``M-Backspace``: delete previous word.
+- ``C-.``: force a kernel restart (a confirmation dialog appears).
 
 
 The IPython pager
 =================
 
 IPython will show long blocks of text from many sources using a builtin pager.
 You can control where this pager appears with the ``--paging`` command-line
 flag:
 
 - default: it is overlaid on top of the main terminal.  You must quit the pager
-  to get back to the terminal (similar to how a kkk pager such as ``less``
-  works).
+  to get back to the terminal (similar to how a pager such as ``less`` or
+  ``more`` works).
 
 - vertical: the console is made double-tall, and the pager appears on the
   bottom area when needed.  You can view its contents while using the terminal.
 
 - horizontal: the console is made double-wide, and the pager appears on the
   right area when needed.  You can view its contents while using the terminal.
 
 If you use the vertical or horizontal paging modes, you can navigate between
 terminal and pager as follows:
 
 - Tab key: goes from pager to terminal (but not the other way around).
 - Control-o: goes from one to another always.
 - Mouse: click on either.
 
-In all cases, the ``q`` or ``Escape`` keys quit the pager.
+In all cases, the ``q`` or ``Escape`` keys quit the pager (when used with the
+focus on the pager area).
 
 
 Running subprocesses
 ====================
 
 The graphical IPython console uses the ``pexpect`` module to run subprocesses
 when you type ``!command``.  This has a number of advantages (true asynchronous
 output from subprocesses as well as very robust termination of rogue
-subprocesses with Control-C), as well as some limitations.  The main limitation
-is that you can *not* interact back with the subprocess, so anything that
-invokes a pager or expects you to type input into it will block and hang (you
-can kill it with Control-C).
-
-We have provided as magics ``%less`` (aliased to ``%more``), ``%clear`` to
-clear the terminal, and ``%man`` on Linux/OSX to cover the most common commands
-you'd want to call in your subshell, but you need to be aware of this
-limitation.
+subprocesses with ``Control-C``), as well as some limitations.  The main
+limitation is that you can *not* interact back with the subprocess, so anything
+that invokes a pager or expects you to type input into it will block and hang
+(you can kill it with ``Control-C``).
+
+We have provided as magics ``%less`` to page files (aliased to ``%more``),
+``%clear`` to clear the terminal, and ``%man`` on Linux/OSX.  These cover the
+most common commands you'd want to call in your subshell and that would cause
+problems if invoked via ``!cmd``, but you need to be aware of this limitation.
 
 
 Inline matplotlib graphics
 ==========================
 
 The IPython console is capable of displaying matplotlib figures inline, in SVG
 format.  If started with the ``--pylab inline`` flag, then all figures are
 rendered inline automatically.  If started with ``--pylab`` or ``--pylab
 <your backend>``, then a GUI backend will be used, but the ``paste()`` function
 is added to the global and ``plt`` namespaces.  You can paste any figure that
 is currently open in a window with this function; type ``paste?`` for
 additional details."""
 
 quick_guide = """\
 ?         -> Introduction and overview of IPython's features.
 %quickref -> Quick reference.
 help      -> Python's own help system.
 object?   -> Details about 'object', use 'object??' for extra details.
 """
 
 gui_note = """\
 %guiref   -> A brief reference about the graphical user interface.
 """
 
 default_banner_parts = [
     'Python %s\n' % (sys.version.split('\n')[0],),
     'Type "copyright", "credits" or "license" for more information.\n\n',
     'IPython %s -- An enhanced Interactive Python.\n' % (release.version,),
     quick_guide
 ]
 
 default_gui_banner_parts = default_banner_parts + [gui_note]
 
 default_banner = ''.join(default_banner_parts)
 
 default_gui_banner = ''.join(default_gui_banner_parts)