questions, no matter how minor, to \email{akuchlin@mems-exchange.org}.
}
-This article explains the new features in Python 2.2. Python 2.2
-includes some significant changes that go far toward cleaning up the
-language's darkest corners, and some exciting new features.
+This article explains the new features in Python 2.2.
+
+Python 2.2 can be thought of as the "cleanup release". There are some
+features such as generators and iterators that are completely new, but
+most of the changes, significant and far-reaching though they may be,
+are aimed at cleaning up irregularities and dark corners of the
+language design.
This article doesn't attempt to provide a complete specification for
-the new features, but instead provides a convenient overview of the
-new features. For full details, you should refer to 2.2 documentation
+the new features, but instead provides a convenient overview. For
+full details, you should refer to the documentation for Python 2.2,
such as the
\citetitle[http://python.sourceforge.net/devel-docs/lib/lib.html]{Python
Library Reference} and the
\citetitle[http://python.sourceforge.net/devel-docs/ref/ref.html]{Python
-Reference Manual}, or to the PEP for a particular new feature.
-% These \citetitle marks should get the python.org URLs for the final
+Reference Manual}.
+% XXX These \citetitle marks should get the python.org URLs for the final
% release, just as soon as the docs are published there.
+If you want to understand the complete implementation and design
+rationale for a change, refer to the PEP for a particular new feature.
The final release of Python 2.2 is planned for October 2001.
%======================================================================
-% It looks like this set of changes will likely get into 2.2,
-% so I need to read and digest the relevant PEPs.
-%\section{PEP 252: Type and Class Changes}
+\section{PEP 252: Type and Class Changes}
+
+XXX
-%XXX
+I need to read and digest the relevant PEPs.
-% GvR's description at http://www.python.org/2.2/descrintro.html
+GvR's description at http://www.python.org/2.2/descrintro.html
-%\begin{seealso}
+\begin{seealso}
-%\seepep{252}{Making Types Look More Like Classes}{Written and implemented
-%by GvR.}
+\seepep{252}{Making Types Look More Like Classes}{Written and implemented
+by Guido van Rossum.}
-%\end{seealso}
+\end{seealso}
%======================================================================
%======================================================================
\section{PEP 237: Unifying Long Integers and Integers}
-XXX write this section
+In recent versions, the distinction between regular integers, which
+are 32-bit values on most machines, and long integers, which can be of
+arbitrary size, was becoming an annoyance. For example, on platforms
+that support large files (files larger than \code{2**32} bytes), the
+\method{tell()} method of file objects has to return a long integer.
+However, there were various bits of Python that expected plain
+integers and would raise an error if a long integer was provided
+instead. For example, in version XXX of Python, only regular integers
+could be used as a slice index, and \code{'abc'[1L:]} would raise a
+\exception{TypeError} exception with the message 'slice index must be
+int'.
+
+Python 2.2 will shift values from short to long integers as required.
+The 'L' suffix is no longer needed to indicate a long integer literal,
+as now the compiler will choose the appropriate type. (Using the 'L'
+suffix will be discouraged in future 2.x versions of Python,
+triggering a warning in Python 2.4, and probably dropped in Python
+3.0.) Many operations that used to raise an \exception{OverflowError}
+will now return a long integer as their result. For example:
+
+\begin{verbatim}
+>>> 1234567890123
+XXX
+>>> 2 ** 32
+XXX put output here
+\end{verbatim}
+In most cases, integers and long integers will now be treated
+identically. You can still distinguish them with the
+\function{type()} built-in function, but that's rarely needed. The
+\function{int()} function will now return a long integer if the value
+is large enough.
+
+% XXX is there a warning-enabling command-line option for this?
+
+\begin{seealso}
+
+\seepep{237}{Unifying Long Integers and Integers}{Written by
+Moshe Zadka and Guido van Rossum. Implemented mostly by Guido van Rossum.}
+
+\end{seealso}
%======================================================================
\section{PEP 238: Changing the Division Operator}
by \cfunction{dlopen()} using the \function{sys.getdlopenflags()} and
\function{sys.setdlopenflags()} functions. (Contributed by Bram Stolk.)
- \item XXX 3-argument float pow() is gone
+ \item The \function{pow()} built-in function no longer supports 3
+ arguments when floating-point numbers are supplied.
+ \code{pow(\var{x}, \var{y}, \var{z})} returns \code{(x**y) % z}, but
+ this is never useful for floating point numbers, and the final
+ result varies unpredictably depending on the platform. A call such
+ as \code{pow(2.0, 8.0, 7.0)} will now raise a \exception{XXX}
+ exception.
\end{itemize}
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