symbian-qemu-0.9.1-12/python-2.6.1/Doc/library/bastion.rst
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+
+:mod:`Bastion` --- Restricting access to objects
+================================================
+
+.. module:: Bastion
+   :synopsis: Providing restricted access to objects.
+   :deprecated:
+   
+.. deprecated:: 2.6
+   The :mod:`Bastion` module has been removed in Python 3.0.
+   
+.. moduleauthor:: Barry Warsaw <bwarsaw@python.org>
+
+
+.. versionchanged:: 2.3
+   Disabled module.
+
+.. warning::
+
+   The documentation has been left in place to help in reading old code that uses
+   the module.
+
+According to the dictionary, a bastion is "a fortified area or position", or
+"something that is considered a stronghold."  It's a suitable name for this
+module, which provides a way to forbid access to certain attributes of an
+object.  It must always be used with the :mod:`rexec` module, in order to allow
+restricted-mode programs access to certain safe attributes of an object, while
+denying access to other, unsafe attributes.
+
+.. I'm concerned that the word 'bastion' won't be understood by people
+.. for whom English is a second language, making the module name
+.. somewhat mysterious.  Thus, the brief definition... --amk
+
+.. I've punted on the issue of documenting keyword arguments for now.
+
+
+.. function:: Bastion(object[, filter[, name[, class]]])
+
+   Protect the object *object*, returning a bastion for the object.  Any attempt to
+   access one of the object's attributes will have to be approved by the *filter*
+   function; if the access is denied an :exc:`AttributeError` exception will be
+   raised.
+
+   If present, *filter* must be a function that accepts a string containing an
+   attribute name, and returns true if access to that attribute will be permitted;
+   if *filter* returns false, the access is denied.  The default filter denies
+   access to any function beginning with an underscore (``'_'``).  The bastion's
+   string representation will be ``<Bastion for name>`` if a value for *name* is
+   provided; otherwise, ``repr(object)`` will be used.
+
+   *class*, if present, should be a subclass of :class:`BastionClass`;  see the
+   code in :file:`bastion.py` for the details.  Overriding the default
+   :class:`BastionClass` will rarely be required.
+
+
+.. class:: BastionClass(getfunc, name)
+
+   Class which actually implements bastion objects.  This is the default class used
+   by :func:`Bastion`.  The *getfunc* parameter is a function which returns the
+   value of an attribute which should be exposed to the restricted execution
+   environment when called with the name of the attribute as the only parameter.
+   *name* is used to construct the :func:`repr` of the :class:`BastionClass`
+   instance.
+