
IDLE
****

IDLE is the Python IDE built with the "tkinter" GUI toolkit.

IDLE has the following features:

* coded in 100% pure Python, using the "tkinter" GUI toolkit

* cross-platform: works on Windows, Unix, and Mac OS X

* multi-window text editor with multiple undo, Python colorizing,
  smart indent, call tips, and many other features

* Python shell window (a.k.a. interactive interpreter)

* debugger (not complete, but you can set breakpoints, view and
  step)


Menus
=====

IDLE has two window types, the Shell window and the Editor window. It
is possible to have multiple editor windows simultaneously. IDLE's
menus dynamically change based on which window is currently selected.
Each menu documented below indicates which window type it is
associated with. Click on the dotted line at the top of a menu to
"tear it off": a separate window containing the menu is created (for
Unix and Windows only).


File menu (Shell and Editor)
----------------------------

New file
   Create a new file editing window

Open...
   Open an existing file

Open module...
   Open an existing module (searches sys.path)

Recent Files
   Open a list of recent files

Class browser
   Show classes and methods in current file

Path browser
   Show sys.path directories, modules, classes and methods

Save
   Save current window to the associated file (unsaved windows have a
   * before and after the window title)

Save As...
   Save current window to new file, which becomes the associated file

Save Copy As...
   Save current window to different file without changing the
   associated file

Print Window
   Print the current window

Close
   Close current window (asks to save if unsaved)

Exit
   Close all windows and quit IDLE (asks to save if unsaved)


Edit menu (Shell and Editor)
----------------------------

Undo
   Undo last change to current window (a maximum of 1000 changes may
   be undone)

Redo
   Redo last undone change to current window

Cut
   Copy selection into system-wide clipboard; then delete the
   selection

Copy
   Copy selection into system-wide clipboard

Paste
   Insert system-wide clipboard into window

Select All
   Select the entire contents of the edit buffer

Find...
   Open a search dialog box with many options

Find again
   Repeat last search

Find selection
   Search for the string in the selection

Find in Files...
   Open a search dialog box for searching files

Replace...
   Open a search-and-replace dialog box

Go to line
   Ask for a line number and show that line

Expand word
   Expand the word you have typed to match another word in the same
   buffer; repeat to get a different expansion

Show call tip
   After an unclosed parenthesis for a function, open a small window
   with function parameter hints

Show surrounding parens
   Highlight the surrounding parenthesis

Show Completions
   Open a scroll window allowing selection keywords and attributes.
   See Completions below.


Format menu (Editor window only)
--------------------------------

Indent region
   Shift selected lines right by the indent width (default 4 spaces)

Dedent region
   Shift selected lines left by the indent width (default 4 spaces)

Comment out region
   Insert ## in front of selected lines

Uncomment region
   Remove leading # or ## from selected lines

Tabify region
   Turns *leading* stretches of spaces into tabs. (Note: We recommend
   using 4 space blocks to indent Python code.)

Untabify region
   Turn *all* tabs into the correct number of spaces

Toggle tabs
   Open a dialog to switch between indenting with spaces and tabs.

New Indent Width
   Open a dialog to change indent width. The accepted default by the
   Python community is 4 spaces.

Format Paragraph
   Reformat the current blank-line-separated paragraph. All lines in
   the paragraph will be formatted to less than 80 columns.

Strip trailing whitespace
   Removes any space characters after the end of the last non-space
   character


Run menu (Editor window only)
-----------------------------

Python Shell
   Open or wake up the Python Shell window

Check module
   Check the syntax of the module currently open in the Editor window.
   If the module has not been saved IDLE will prompt the user to save
   the code.

Run module
   Restart the shell to clean the environment, then execute the
   currently open module.  If the module has not been saved IDLE will
   prompt the user to save the code.


Shell menu (Shell window only)
------------------------------

View Last Restart
   Scroll the shell window to the last Shell restart

Restart Shell
   Restart the shell to clean the environment


Debug menu (Shell window only)
------------------------------

Go to file/line
   Look around the insert point for a filename and line number, open
   the file, and show the line.  Useful to view the source lines
   referenced in an exception traceback. Available in the context menu
   of the Shell window.

Debugger (toggle)
   This feature is not complete and considered experimental. Run
   commands in the shell under the debugger

Stack viewer
   Show the stack traceback of the last exception

Auto-open Stack Viewer
   Toggle automatically opening the stack viewer on unhandled
   exception


Options menu (Shell and Editor)
-------------------------------

Configure IDLE
   Open a configuration dialog.  Fonts, indentation, keybindings, and
   color themes may be altered.  Startup Preferences may be set, and
   additional help sources can be specified.

Code Context (toggle)(Editor Window only)
   Open a pane at the top of the edit window which shows the block
   context of the section of code which is scrolling off the top of
   the window.


Windows menu (Shell and Editor)
-------------------------------

Zoom Height
   Toggles the window between normal size (40x80 initial setting) and
   maximum height. The initial size is in the Configure IDLE dialog
   under the general tab.

The rest of this menu lists the names of all open windows; select one
to bring it to the foreground (deiconifying it if necessary).


Help menu (Shell and Editor)
----------------------------

About IDLE
   Version, copyright, license, credits

IDLE Help
   Display a help file for IDLE detailing the menu options, basic
   editing and navigation, and other tips.

Python Docs
   Access local Python documentation, if installed. Or will start a
   web browser and open docs.python.org showing the latest Python
   documentation.

Additional help sources may be added here with the Configure IDLE
dialog under the General tab.


Editor Window context menu
--------------------------

* Right-click in Editor window (Control-click on OS X)

Cut
   Copy selection into system-wide clipboard; then delete selection

Copy
   Copy selection into system-wide clipboard

Paste
   Insert system-wide clipboard into window

Set Breakpoint
   Sets a breakpoint.  Breakpoints are only enabled when the debugger
   is open.

Clear Breakpoint
   Clears the breakpoint on that line.


Shell Window context menu
-------------------------

* Right-click in Python Shell window (Control-click on OS X)

Cut
   Copy selection into system-wide clipboard; then delete selection

Copy
   Copy selection into system-wide clipboard

Paste
   Insert system-wide clipboard into window

Go to file/line
   Same as in Debug menu.


Editing and navigation
======================

* "Backspace" deletes to the left; "Del" deletes to the right

* "C-Backspace" delete word left; "C-Del" delete word to the right

* Arrow keys and "Page Up"/"Page Down" to move around

* "C-LeftArrow" and "C-RightArrow" moves by words

* "Home"/"End" go to begin/end of line

* "C-Home"/"C-End" go to begin/end of file

* Some useful Emacs bindings are inherited from Tcl/Tk:

     * "C-a" beginning of line

     * "C-e" end of line

     * "C-k" kill line (but doesn't put it in clipboard)

     * "C-l" center window around the insertion point

     * "C-b" go backwards one character without deleting (usually
       you can also use the cursor key for this)

     * "C-f" go forward one character without deleting (usually you
       can also use the cursor key for this)

     * "C-p" go up one line (usually you can also use the cursor key
       for this)

     * "C-d" delete next character

Standard keybindings (like "C-c" to copy and "C-v" to paste) may work.
Keybindings are selected in the Configure IDLE dialog.


Automatic indentation
---------------------

After a block-opening statement, the next line is indented by 4 spaces
(in the Python Shell window by one tab).  After certain keywords
(break, return etc.) the next line is dedented.  In leading
indentation, "Backspace" deletes up to 4 spaces if they are there.
"Tab" inserts spaces (in the Python Shell window one tab), number
depends on Indent width. Currently tabs are restricted to four spaces
due to Tcl/Tk limitations.

See also the indent/dedent region commands in the edit menu.


Completions
-----------

Completions are supplied for functions, classes, and attributes of
classes, both built-in and user-defined. Completions are also provided
for filenames.

The AutoCompleteWindow (ACW) will open after a predefined delay
(default is two seconds) after a '.' or (in a string) an os.sep is
typed. If after one of those characters (plus zero or more other
characters) a tab is typed the ACW will open immediately if a possible
continuation is found.

If there is only one possible completion for the characters entered, a
"Tab" will supply that completion without opening the ACW.

'Show Completions' will force open a completions window, by default
the "C-space" will open a completions window. In an empty string, this
will contain the files in the current directory. On a blank line, it
will contain the built-in and user-defined functions and classes in
the current name spaces, plus any modules imported. If some characters
have been entered, the ACW will attempt to be more specific.

If a string of characters is typed, the ACW selection will jump to the
entry most closely matching those characters.  Entering a "tab" will
cause the longest non-ambiguous match to be entered in the Editor
window or Shell.  Two "tab" in a row will supply the current ACW
selection, as will return or a double click.  Cursor keys, Page
Up/Down, mouse selection, and the scroll wheel all operate on the ACW.

"Hidden" attributes can be accessed by typing the beginning of hidden
name after a '.', e.g. '_'. This allows access to modules with
"__all__" set, or to class-private attributes.

Completions and the 'Expand Word' facility can save a lot of typing!

Completions are currently limited to those in the namespaces. Names in
an Editor window which are not via "__main__" and "sys.modules" will
not be found.  Run the module once with your imports to correct this
situation. Note that IDLE itself places quite a few modules in
sys.modules, so much can be found by default, e.g. the re module.

If you don't like the ACW popping up unbidden, simply make the delay
longer or disable the extension.  Or another option is the delay could
be set to zero. Another alternative to preventing ACW popups is to
disable the call tips extension.


Python Shell window
-------------------

* "C-c" interrupts executing command

* "C-d" sends end-of-file; closes window if typed at a ">>>" prompt
  (this is "C-z" on Windows).

* "Alt-/" (Expand word) is also useful to reduce typing

  Command history

  * "Alt-p" retrieves previous command matching what you have typed.
    On OS X use "C-p".

  * "Alt-n" retrieves next. On OS X use "C-n".

  * "Return" while on any previous command retrieves that command


Syntax colors
=============

The coloring is applied in a background "thread," so you may
occasionally see uncolorized text.  To change the color scheme, edit
the "[Colors]" section in "config.txt".

Python syntax colors:
   Keywords
      orange

   Strings
      green

   Comments
      red

   Definitions
      blue

Shell colors:
   Console output
      brown

   stdout
      blue

   stderr
      dark green

   stdin
      black


Startup
=======

Upon startup with the "-s" option, IDLE will execute the file
referenced by the environment variables "IDLESTARTUP" or
"PYTHONSTARTUP". IDLE first checks for "IDLESTARTUP"; if "IDLESTARTUP"
is present the file referenced is run.  If "IDLESTARTUP" is not
present, IDLE checks for "PYTHONSTARTUP".  Files referenced by these
environment variables are convenient places to store functions that
are used frequently from the IDLE shell, or for executing import
statements to import common modules.

In addition, "Tk" also loads a startup file if it is present.  Note
that the Tk file is loaded unconditionally.  This additional file is
".Idle.py" and is looked for in the user's home directory.  Statements
in this file will be executed in the Tk namespace, so this file is not
useful for importing functions to be used from IDLE's Python shell.


Command line usage
------------------

   idle.py [-c command] [-d] [-e] [-s] [-t title] [arg] ...

   -c command  run this command
   -d          enable debugger
   -e          edit mode; arguments are files to be edited
   -s          run $IDLESTARTUP or $PYTHONSTARTUP first
   -t title    set title of shell window

If there are arguments:

1. If "-e" is used, arguments are files opened for editing and
   "sys.argv" reflects the arguments passed to IDLE itself.

2. Otherwise, if "-c" is used, all arguments are placed in
   "sys.argv[1:...]", with "sys.argv[0]" set to "'-c'".

3. Otherwise, if neither "-e" nor "-c" is used, the first argument
   is a script which is executed with the remaining arguments in
   "sys.argv[1:...]"  and "sys.argv[0]" set to the script name.  If
   the script name is '-', no script is executed but an interactive
   Python session is started; the arguments are still available in
   "sys.argv".


Additional help sources
=======================

IDLE includes a help menu entry called "Python Docs" that will open
the extensive sources of help, including tutorials, available at
docs.python.org. Selected URLs can be added or removed from the help
menu at any time using the Configure IDLE dialog. See the IDLE help
option in the help menu of IDLE for more information.


Other preferences
=================

The font preferences, highlighting, keys, and general preferences can
be changed via the Configure IDLE menu option.  Be sure to note that
keys can be user defined, IDLE ships with four built in key sets. In
addition a user can create a custom key set in the Configure IDLE
dialog under the keys tab.


Extensions
==========

IDLE contains an extension facility.  See the beginning of config-
extensions.def in the idlelib directory for further information.  The
default extensions are currently:

* FormatParagraph

* AutoExpand

* ZoomHeight

* ScriptBinding

* CallTips

* ParenMatch

* AutoComplete

* CodeContext
