Move UserString to collections.

Removed decode() method.  Added isidentifier() and format() methods.
Drop MutableUserString class.

3 files changed, 19 insertions, 62 deletions

diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
index bb2140c..1d6687d 100644
--- a/Doc/library/collections.rst
+++ b/Doc/library/collections.rst
@@ -706,3 +706,22 @@ If a derived class does not wish to comply with this requirement, all of the
 special methods supported by this class will need to be overridden; please
 consult the sources for information about the methods which need to be provided
 in that case.
+
+:class:`UserString` objects
+-------------------------
+
+The class, :class:`UserString` acts as a wrapper around string objects.  
+The need for this class has been partially supplanted by the ability to 
+subclass directly from :class:`str`; however, this class can be easier
+to work with because the underlying string is accessible as an
+attribute.
+
+.. class:: UserString([sequence])
+
+   Class that simulates a string or a Unicode string object.  The instance's
+   content is kept in a regular string object, which is accessible via the 
+   :attr:`data` attribute of :class:`UserString` instances.  The instance's 
+   contents are initially set to a copy of *sequence*.  The *sequence* can
+   be an instance of :class:`bytes`, :class:`str`, :class:`UserString` (or a
+   subclass) or an arbitrary sequence which can be converted into a string using
+   the built-in :func:`str` function.
diff --git a/Doc/library/datatypes.rst b/Doc/library/datatypes.rst
index 496fd41..ae76e72 100644
--- a/Doc/library/datatypes.rst
+++ b/Doc/library/datatypes.rst
@@ -29,7 +29,6 @@ The following modules are documented in this chapter:
    mutex.rst
    queue.rst
    weakref.rst
-   userdict.rst
    types.rst
    copy.rst
    pprint.rst
diff --git a/Doc/library/userdict.rst b/Doc/library/userdict.rst
deleted file mode 100644
index ebdec7c..0000000
--- a/Doc/library/userdict.rst
+++ /dev/null
@@ -1,61 +0,0 @@
-
-:mod:`UserString` --- Class wrapper for string objects
-======================================================
-
-.. module:: UserString
-   :synopsis: Class wrapper for string objects.
-.. moduleauthor:: Peter Funk <pf@artcom-gmbh.de>
-.. sectionauthor:: Peter Funk <pf@artcom-gmbh.de>
-
-
-.. note::
-
-   This :class:`UserString` class from this module is available for backward
-   compatibility only.  If you are writing code that does not need to work with
-   versions of Python earlier than Python 2.2, please consider subclassing directly
-   from the built-in :class:`str` type instead of using :class:`UserString` (there
-   is no built-in equivalent to :class:`MutableString`).
-
-This module defines a class that acts as a wrapper around string objects.  It is
-a useful base class for your own string-like classes, which can inherit from
-them and override existing methods or add new ones.  In this way one can add new
-behaviors to strings.
-
-It should be noted that these classes are highly inefficient compared to real
-string or bytes objects; this is especially the case for
-:class:`MutableString`.
-
-The :mod:`UserString` module defines the following classes:
-
-
-.. class:: UserString([sequence])
-
-   Class that simulates a string or a Unicode string object.  The instance's
-   content is kept in a regular string or Unicode string object, which is
-   accessible via the :attr:`data` attribute of :class:`UserString` instances.  The
-   instance's contents are initially set to a copy of *sequence*.  *sequence* can
-   be an instance of :class:`bytes`, :class:`str`, :class:`UserString` (or a
-   subclass) or an arbitrary sequence which can be converted into a string using
-   the built-in :func:`str` function.
-
-
-.. class:: MutableString([sequence])
-
-   This class is derived from the :class:`UserString` above and redefines strings
-   to be *mutable*.  Mutable strings can't be used as dictionary keys, because
-   dictionaries require *immutable* objects as keys.  The main intention of this
-   class is to serve as an educational example for inheritance and necessity to
-   remove (override) the :meth:`__hash__` method in order to trap attempts to use a
-   mutable object as dictionary key, which would be otherwise very error prone and
-   hard to track down.
-
-In addition to supporting the methods and operations of bytes and string
-objects (see section :ref:`string-methods`), :class:`UserString` instances
-provide the following attribute:
-
-
-.. attribute:: MutableString.data
-
-   A real Python string or bytes object used to store the content of the
-   :class:`UserString` class.
-