implemented by Jiwon Seo with early efforts steered by Hye-Shik Chang.}
\end{seealso}
+
+%======================================================================
+\section{PEP 292: Simpler String Substitutions}
+
+Some new classes in the standard library provide a
+alternative mechanism for substituting variables into strings that's
+better-suited for applications where untrained users need to edit templates.
+
+The usual way of substituting variables by name is the \code{\%}
+operator:
+
+\begin{verbatim}
+>>> '%(page)i: %(title)s' % {'page':2, 'title': 'The Best of Times'}
+'2: The Best of Times'
+\end{verbatim}
+
+When writing the template string, it can be easy to forget the
+\samp{i} or \samp{s} after the closing parenthesis. This isn't a big
+problem if the template is in a Python module, because you run the
+code, get an ``Unsupported format character'' \exception{ValueError},
+and fix the problem. However, consider an application such as Mailman
+where template strings or translations are being edited by users who
+aren't aware of the Python language; the syntax is complicated to
+explain to such users, and if they make a mistake, it's difficult to
+provide helpful feedback to them.
+
+PEP 292 adds a \class{Template} class to the \module{string} module
+that uses \samp{\$} to indicate a substitution. \class{Template} is a
+subclass of the built-in Unicode type, so the result is always a
+Unicode string:
+
+\begin{verbatim}
+>>> import string
+>>> t = string.Template('$page: $title')
+>>> t % {'page':2, 'title': 'The Best of Times'}
+u'2: The Best of Times'
+>>> t2 % {'cost':42.50, 'action':'polish'}
+u'$ 42.5: polishing'
+\end{verbatim}
+
+% $ Terminate $-mode for Emacs
+
+If a key is missing from the dictionary, the \class{Template} class
+will raise a \exception{KeyError}. There's also a \class{SafeTemplate}
+class that ignores missing keys:
+
+\begin{verbatim}
+>>> t = string.SafeTemplate('$page: $title')
+>>> t % {'page':3}
+u'3: $title'
+\end{verbatim}
+
+Because templates are Unicode strings, you can use a template with the
+\module{gettext} module to look up translated versions of a message.
+
+\begin{seealso}
+\seepep{292}{Simpler String Substitutions}{Written and implemented
+by Barry Warsaw.}
+\end{seealso}
+
+
%======================================================================
\section{PEP 318: Decorators for Functions, Methods and Classes}
Getting this right can be slightly brain-bending, but it's not too
difficult.
+A small related change makes the \member{func_name} attribute of
+functions writable. This attribute is used to display function names
+in tracebacks, so decorators should change the name of any new
+function that's constructed and returned.
+
The new syntax was provisionally added in 2.4alpha2, and is subject to
change during the 2.4alpha release cycle depending on the Python
community's reaction. Post-2.4 versions of Python will preserve
yellow 5
\end{verbatim}
+\item Integer operations will no longer trigger an \exception{OverflowWarning}.
+The \exception{OverflowWarning} warning will disappear in Python 2.5.
+
\item The \function{eval(\var{expr}, \var{globals}, \var{locals})}
and \function{execfile(\var{filename}, \var{globals}, \var{locals})}
functions and the \keyword{exec} statement now accept any mapping type
\item Korean: cp949, euc-kr, johab, iso-2022-kr
\end{itemize}
-\item Some other new encodings were added: ISO_8859-11, ISO_8859-16, PCTP-154,
+\item Some other new encodings were added: HP Roman8,
+ISO_8859-11, ISO_8859-16, PCTP-154,
and TIS-620.
\item There is a new \module{collections} module for
the group didn't match, the pattern \var{B} will be used instead.
\item A new \function{socketpair()} function was added to the
- \module{socket} module, returning a pair of connected sockets.
- (Contributed by Dave Cole.)
+\module{socket} module, returning a pair of connected sockets.
+(Contributed by Dave Cole.)
% XXX sre is now non-recursive.
+\item The \function{sys.exitfunc()} function has been deprecated. Code
+should be using the existing \module{atexit} module, which correctly
+handles calling multiple exit functions. Eventually
+\function{sys.exitfunc()} will become a purely internal interface,
+accessed only by \module{atexit}.
+
+\item The \module{tarfile} module now generates GNU-format tar files
+by default.
+
\item The \module{threading} module now has an elegantly simple way to support
thread-local data. The module contains a \class{local} class whose
attribute values are local to different threads.
\class{HTTPCookieProcessor} manages a cookie jar that is used when
accessing URLs.
+\subsection{doctest}
+
+The \module{doctest} module underwent considerable refactoring thanks
+to Edward Loper and Tim Peters.
+
+% XXX describe this
+
% ======================================================================
\section{Build and C API Changes}
same name. This can halve the access time for a method such as
\method{set.__contains__()}.
- \item Python can now be built with additional profiling for the interpreter
- itself. This is intended for people developing on the Python core.
- Providing \longprogramopt{--enable-profiling} to the
- \program{configure} script will let you profile the interpreter with
- \program{gprof}, and providing the \longprogramopt{--with-tsc} switch
- enables profiling using the Pentium's Time-Stamp-Counter register.
-
+ \item Python can now be built with additional profiling for the
+ interpreter itself. This is intended for people developing on the
+ Python core. Providing \longprogramopt{--enable-profiling} to the
+ \program{configure} script will let you profile the interpreter with
+ \program{gprof}, and providing the \longprogramopt{--with-tsc}
+ switch enables profiling using the Pentium's Time-Stamp-Counter
+ register. The switch is slightly misnamed, because the profiling
+ feature also works on the PowerPC platform, though that processor
+ architecture doesn't called that register the TSC.
+
\item The \ctype{tracebackobject} type has been renamed to \ctype{PyTracebackObject}.
\end{itemize}
\item \function{fcntl.ioctl} now warns if the \var{mutate}
argument is omitted and relevant.
+\item The \module{tarfile} module now generates GNU-format tar files
+by default.
+
\end{itemize}
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