Note that the UserString/MutableString classes are far less efficient

than the built-in string types (suggested by Moshe Zadka
<moshez@math.huji.ac.il>).

Clarified what "can be converted to a string" means.

Fixed a few markup nits.

Doc/lib/libuserdict.tex

@@ -92,23 +92,26 @@ methods which need to be provided in that case.
 \moduleauthor{Peter Funk}{pf@artcom-gmbh.de}
 \sectionauthor{Peter Funk}{pf@artcom-gmbh.de}
 
-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.
+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.
 
-The \module{UserString} module defines the \class{UserString} class:
+It should be noted that these classes are highly inefficient compared
+to real string or Unicode objects; this is especially the case for
+\class{MutableString}.
+
+The \module{UserString} module defines the following classes:
 
 \begin{classdesc}{UserString}{\optional{sequence}}
-Return a class instance 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
-\member{data} attribute of \class{UserString} instances.  The instance's
-contents are initially set to a copy of \var{sequence}.
-\var{sequence} can be either a regular Python string or Unicode string,
-an instance of \class{UserString} (or a subclass) or an arbitrary sequence
-which can be converted into a string.
+Return a class instance 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 \member{data} attribute of
+\class{UserString} instances.  The instance's contents are initially
+set to a copy of \var{sequence}.  \var{sequence} can be either a
+regular Python string or Unicode string, an instance of
+\class{UserString} (or a subclass) or an arbitrary sequence which can
+be converted into a string using the built-in \function{str()} function.
 \end{classdesc}
 
 \begin{classdesc}{MutableString}{\optional{sequence}}
@@ -117,14 +120,15 @@ strings to be \emph{mutable}.  Mutable strings can't be used as
 dictionary keys, because dictionaries require \emph{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
-\function{__hash__} method in order to trap attempts to use a
+\method{__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.
 \end{classdesc}
 
-In addition to supporting the methods and operations of string  or
-Unicode objects (see section \ref{typesseq}), \class{UserString} instances
-provide the following attribute:
+In addition to supporting the methods and operations of string and
+Unicode objects (see section \ref{string-methods}, ``String
+Methods''), \class{UserString} instances provide the following
+attribute:
 
 \begin{memberdesc}{data}
 A real Python string or Unicode object used to store the content of the