cpython/Doc/library/rlcompleter.rst

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:mod:`rlcompleter` --- Completion function for GNU readline
===========================================================
.. module:: rlcompleter
:synopsis: Python identifier completion, suitable for the GNU readline library.
.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
**Source code:** :source:`Lib/rlcompleter.py`
--------------
The :mod:`!rlcompleter` module defines a completion function suitable to be
passed to :func:`~readline.set_completer` in the :mod:`readline` module.
When this module is imported on a Unix platform with the :mod:`readline` module
available, an instance of the :class:`Completer` class is automatically created
and its :meth:`~Completer.complete` method is set as the
:ref:`readline completer <readline-completion>`. The method provides
completion of valid Python :ref:`identifiers and keywords <identifiers>`.
Example::
>>> import rlcompleter
>>> import readline
>>> readline.parse_and_bind("tab: complete")
>>> readline. <TAB PRESSED>
readline.__doc__ readline.get_line_buffer( readline.read_init_file(
readline.__file__ readline.insert_text( readline.set_completer(
readline.__name__ readline.parse_and_bind(
>>> readline.
The :mod:`!rlcompleter` module is designed for use with Python's
:ref:`interactive mode <tut-interactive>`. Unless Python is run with the
:option:`-S` option, the module is automatically imported and configured
(see :ref:`rlcompleter-config`).
On platforms without :mod:`readline`, the :class:`Completer` class defined by
this module can still be used for custom purposes.
.. _completer-objects:
.. class:: Completer
Completer objects have the following method:
.. method:: Completer.complete(text, state)
Return the next possible completion for *text*.
When called by the :mod:`readline` module, this method is called
successively with ``state == 0, 1, 2, ...`` until the method returns
``None``.
If called for *text* that doesn't include a period character (``'.'``), it will
complete from names currently defined in :mod:`__main__`, :mod:`builtins` and
keywords (as defined by the :mod:`keyword` module).
If called for a dotted name, it will try to evaluate anything without obvious
side-effects (functions will not be evaluated, but it can generate calls to
:meth:`~object.__getattr__`) up to the last part, and find matches for the
rest via the :func:`dir` function. Any exception raised during the
evaluation of the expression is caught, silenced and :const:`None` is
returned.