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Give the enumerate() PEP a section of its own

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Andrew M. Kuchling 2002-05-10 21:00:05 +00:00
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Doc/whatsnew/whatsnew23.tex
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@ -215,10 +215,45 @@ and implemented by Jack Jansen.}
\end{seealso}
%======================================================================
\section{PEP 279: The \function{enumerate()} Built-in Function}
A new built-in function, \function{enumerate()}, will make
certain loops a bit clearer. \code{enumerate(thing)}, where
\var{thing} is either an iterator or a sequence, returns a iterator
that will return \code{(0, \var{thing[0]})}, \code{(1,
\var{thing[1]})}, \code{(2, \var{thing[2]})}, and so forth. Fairly
often you'll see code to change every element of a list that looks
like this:
\begin{verbatim}
for i in range(len(L)):
item = L[i]
# ... compute some result based on item ...
L[i] = result
\end{verbatim}
This can be rewritten using \function{enumerate()} as:
\begin{verbatim}
for i, item in enumerate(L):
# ... compute some result based on item ...
L[i] = result
\end{verbatim}
\begin{seealso}
\seepep{279}{The enumerate() built-in function}{Written
by Raymond D. Hettinger.}
\end{seealso}
%======================================================================
\section{PEP 285: The \class{bool} Type\label{section-bool}}
A Boolean type was added to Python 2.3. Two new constants were added
to the \module{__builtin__} module, \constant{True} and
\constant{False}. The type object for this new type is named
@ -292,41 +327,20 @@ strings \samp{True} and \samp{False} instead of \samp{1} and \samp{0}.
%======================================================================
\section{Other Language Changes}
%\section{Other Language Changes}
Here are the changes that Python 2.3 makes to the core language.
%Here are the changes that Python 2.3 makes to the core language.
\begin{itemize}
\item The \keyword{yield} statement is now always a keyword, as
described in section~\ref{section-generators}.
%\begin{itemize}
%\item The \keyword{yield} statement is now always a keyword, as
%described in section~\ref{section-generators}.
\item Two new constants, \constant{True} and \constant{False} were
added along with the built-in \class{bool} type, as described in
section~\ref{section-bool}.
%\item Two new constants, \constant{True} and \constant{False} were
%added along with the built-in \class{bool} type, as described in
%section~\ref{section-bool}.
\item A new built-in function, \function{enumerate()}, will make
certain loops a bit clearer. \code{enumerate(thing)}, where
\var{thing} is either an iterator or a sequence, returns a iterator
that will return \code{(0, \var{thing[0]})}, \code{(1,
\var{thing[1]})}, \code{(2, \var{thing[2]})}, and so forth. Fairly
often you'll see code to change every element of a list that looks like this:
\begin{verbatim}
for i in range(len(L)):
item = L[i]
# ... compute some result based on item ...
L[i] = result
\end{verbatim}
This can be rewritten using \function{enumerate()} as:
\begin{verbatim}
for i, item in enumerate(L):
# ... compute some result based on item ...
L[i] = result
\end{verbatim}
\end{itemize}
%\item
%\end{itemize}
%======================================================================
@ -386,7 +400,7 @@ support, turn on the Python interpreter's debugging code by running
\begin{seealso}
\seeurl{XXX}
\seeurl{http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/python/python/dist/src/Objects/obmalloc.c}
{For the full details of the pymalloc implementation, see
the comments at the top of the file \file{Objects/obmalloc.c} in the
Python source code. The above link points to the file within the
@ -491,7 +505,7 @@ packages for use on HP-UX. (Contributed by Mark Alexander.)
characters using the \samp{u} format character. Arrays also
now support using the \code{+=} assignment operator to add another array's
contents, and the \code{*=} assignment operator to repeat an array.
(Contributed by XXX.)
(Contributed by Jason Orendorff.)
\item The \module{grp} module now returns enhanced tuples:
@ -518,8 +532,8 @@ Changes to Python's build process, and to the C API, include:
\item Python can now optionally be built as a shared library
(\file{libpython2.3.so}) by supplying \longprogramopt{enable-shared}
when running Python's \file{configure} script. (Contributed by XXX
Patch \#527027)
when running Python's \file{configure} script. (Contributed by Ondrej
Palkovsky.)
\item The \cfunction{PyArg_NoArgs()} macro is now deprecated, and code
that