Doc/library/pyclbr.rst

:mod:`!pyclbr` --- Python module browser support
================================================

.. module:: pyclbr
   :synopsis: Supports information extraction for a Python module browser.

.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>

**Source code:** :source:`Lib/pyclbr.py`

--------------

The :mod:`pyclbr` module provides limited information about the
functions, classes, and methods defined in a Python-coded module.  The
information is sufficient to implement a module browser.  The
information is extracted from the Python source code rather than by
importing the module, so this module is safe to use with untrusted code.
This restriction makes it impossible to use this module with modules not
implemented in Python, including all standard and optional extension
modules.


.. function:: readmodule(module, path=None)

   Return a dictionary mapping module-level class names to class
   descriptors.  If possible, descriptors for imported base classes are
   included.  Parameter *module* is a string with the name of the module
   to read; it may be the name of a module within a package.  If given,
   *path* is a sequence of directory paths prepended to ``sys.path``,
   which is used to locate the module source code.

   This function is the original interface and is only kept for back
   compatibility.  It returns a filtered version of the following.


.. function:: readmodule_ex(module, path=None)

   Return a dictionary-based tree containing a function or class
   descriptors for each function and class defined in the module with a
   ``def`` or ``class`` statement.  The returned dictionary maps
   module-level function and class names to their descriptors.  Nested
   objects are entered into the children dictionary of their parent.  As
   with readmodule, *module* names the module to be read and *path* is
   prepended to sys.path.  If the module being read is a package, the
   returned dictionary has a key ``'__path__'`` whose value is a list
   containing the package search path.

.. versionadded:: 3.7
   Descriptors for nested definitions.  They are accessed through the
   new children attribute.  Each has a new parent attribute.

The descriptors returned by these functions are instances of
Function and Class classes.  Users are not expected to create instances
of these classes.


.. _pyclbr-function-objects:

Function Objects
----------------

.. class:: Function

   Class :class:`!Function` instances describe functions defined by def
   statements.  They have the following attributes:


   .. attribute:: file

      Name of the file in which the function is defined.


   .. attribute:: module

      The name of the module defining the function described.


   .. attribute:: name

      The name of the function.


   .. attribute:: lineno

      The line number in the file where the definition starts.


   .. attribute:: parent

      For top-level functions, ``None``.  For nested functions, the parent.

      .. versionadded:: 3.7


   .. attribute:: children

      A :class:`dictionary <dict>` mapping names to descriptors for nested functions and
      classes.

      .. versionadded:: 3.7


   .. attribute:: is_async

      ``True`` for functions that are defined with the
      :keyword:`async <async def>` prefix, ``False`` otherwise.

      .. versionadded:: 3.10


.. _pyclbr-class-objects:

Class Objects
-------------

.. class:: Class

   Class :class:`!Class` instances describe classes defined by class
   statements.  They have the same attributes as :class:`Functions <Function>`
   and two more.


   .. attribute:: file

      Name of the file in which the class is defined.


   .. attribute:: module

      The name of the module defining the class described.


   .. attribute:: name

      The name of the class.


   .. attribute:: lineno

      The line number in the file where the definition starts.


   .. attribute:: parent

      For top-level classes, ``None``.  For nested classes, the parent.

      .. versionadded:: 3.7


   .. attribute:: children

      A dictionary mapping names to descriptors for nested functions and
      classes.

      .. versionadded:: 3.7


   .. attribute:: super

      A list of :class:`!Class` objects which describe the immediate base
      classes of the class being described.  Classes which are named as
      superclasses but which are not discoverable by :func:`readmodule_ex`
      are listed as a string with the class name instead of as
      :class:`!Class` objects.


   .. attribute:: methods

      A :class:`dictionary <dict>` mapping method names to line numbers.
      This can be derived from the newer :attr:`children` dictionary,
      but remains for
      back-compatibility.