[Python-checkins] python/dist/src/Doc/whatsnew whatsnew23.tex,1.45,1.46

[akuchling@users.sourceforge.net]

Update of /cvsroot/python/python/dist/src/Doc/whatsnew
In directory usw-pr-cvs1:/tmp/cvs-serv21554

Modified Files:
	whatsnew23.tex 
Log Message:
Create two subsections of the "Core Language Changes" section, because 
   the list is getting awfully long
Mention Karatsuba multiplication and some other items


Index: whatsnew23.tex
===================================================================
RCS file: /cvsroot/python/python/dist/src/Doc/whatsnew/whatsnew23.tex,v
retrieving revision 1.45
retrieving revision 1.46
diff -C2 -d -r1.45 -r1.46
*** whatsnew23.tex	15 Aug 2002 14:59:00 -0000	1.45
--- whatsnew23.tex	20 Aug 2002 00:54:36 -0000	1.46
***************
*** 17,22 ****
  % New sorting code
  %
- % Karatsuba multiplication for long ints (#560379)
- %
  % xreadlines obsolete; files are their own iterator
  
--- 17,20 ----
***************
*** 501,524 ****
  described in section~\ref{section-generators} of this document.
  
- \item The \code{in} operator now works differently for strings.
- Previously, when evaluating \code{\var{X} in \var{Y}} where \var{X}
- and \var{Y} are strings, \var{X} could only be a single character.
- That's now changed; \var{X} can be a string of any length, and
- \code{\var{X} in \var{Y}} will return \constant{True} if \var{X} is a
- substring of \var{Y}.  If \var{X} is the empty string, the result is
- always \constant{True}.
- 
- \begin{verbatim}
- >>> 'ab' in 'abcd'
- True
- >>> 'ad' in 'abcd'
- False
- >>> '' in 'abcd'
- True
- \end{verbatim}
- 
- Note that this doesn't tell you where the substring starts; the
- \method{find()} method is still necessary to figure that out.
- 
  \item A new built-in function \function{enumerate()} 
  was added, as described in section~\ref{section-enumerate} of this
--- 499,502 ----
***************
*** 559,562 ****
--- 537,619 ----
  (Patch contributed by Raymond Hettinger.)
  
+ \item The \keyword{assert} statement no longer  checks the \code{__debug__}
+ flag, so you can no longer disable assertions by assigning to \code{__debug__}.
+ Running Python with the \programopt{-O} switch will still generate 
+ code that doesn't execute any assertions.
+ 
+ \item Most type objects are now callable, so you can use them
+ to create new objects such as functions, classes, and modules.  (This
+ means that the \module{new} module can be deprecated in a future
+ Python version, because you can now use the type objects available
+ in the \module{types} module.)
+ % XXX should new.py use PendingDeprecationWarning?
+ For example, you can create a new module object with the following code:
+ 
+ \begin{verbatim}
+ >>> import types
+ >>> m = types.ModuleType('abc','docstring')
+ >>> m
+ <module 'abc' (built-in)>
+ >>> m.__doc__
+ 'docstring'
+ \end{verbatim}
+ 
+ \item 
+ A new warning, \exception{PendingDeprecationWarning} was added to
+ indicate features which are in the process of being
+ deprecated.  The warning will \emph{not} be printed by default.  To
+ check for use of features that will be deprecated in the future,
+ supply \programopt{-Walways::PendingDeprecationWarning::} on the
+ command line or use \function{warnings.filterwarnings()}.
+ 
+ \item Using \code{None} as a variable name will now result in a
+ \exception{SyntaxWarning} warning.  In a future version of Python,
+ \code{None} may finally become a keyword.
+ 
+ \item One minor but far-reaching change is that the names of extension
+ types defined by the modules included with Python now contain the
+ module and a \samp{.} in front of the type name.  For example, in
+ Python 2.2, if you created a socket and printed its
+ \member{__class__}, you'd get this output:
+ 
+ \begin{verbatim}
+ >>> s = socket.socket()
+ >>> s.__class__
+ <type 'socket'>
+ \end{verbatim}
+ 
+ In 2.3, you get this:
+ \begin{verbatim}
+ >>> s.__class__
+ <type '_socket.socket'>
+ \end{verbatim}
+ 
+ \end{itemize}
+ 
+ 
+ \subsection{String Changes}
+ 
+ \begin{itemize}
+ 
+ \item The \code{in} operator now works differently for strings.
+ Previously, when evaluating \code{\var{X} in \var{Y}} where \var{X}
+ and \var{Y} are strings, \var{X} could only be a single character.
+ That's now changed; \var{X} can be a string of any length, and
+ \code{\var{X} in \var{Y}} will return \constant{True} if \var{X} is a
+ substring of \var{Y}.  If \var{X} is the empty string, the result is
+ always \constant{True}.
+ 
+ \begin{verbatim}
+ >>> 'ab' in 'abcd'
+ True
+ >>> 'ad' in 'abcd'
+ False
+ >>> '' in 'abcd'
+ True
+ \end{verbatim}
+ 
+ Note that this doesn't tell you where the substring starts; the
+ \method{find()} method is still necessary to figure that out.
+ 
  \item The \method{strip()}, \method{lstrip()}, and \method{rstrip()}
  string methods now have an optional argument for specifying the
***************
*** 599,607 ****
  (Contributed by Walter D\"orwald.)
  
- \item The \keyword{assert} statement no longer  checks the \code{__debug__}
- flag, so you can no longer disable assertions by assigning to \code{__debug__}.
- Running Python with the \programopt{-O} switch will still generate 
- code that doesn't execute any assertions.
- 
  \item A new type object, \class{basestring}, has been added.  
     Both 8-bit strings and Unicode strings inherit from this type, so
--- 656,659 ----
***************
*** 610,661 ****
     can't create \class{basestring} instances.
  
! \item The \method{sort()} method of list objects has been extensively
! rewritten by Tim Peters, and the implementation is significantly
! faster.
  
! \item Most type objects are now callable, so you can use them
! to create new objects such as functions, classes, and modules.  (This
! means that the \module{new} module can be deprecated in a future
! Python version, because you can now use the type objects available
! in the \module{types} module.)
! % XXX should new.py use PendingDeprecationWarning?
! For example, you can create a new module object with the following code:
  
- \begin{verbatim}
- >>> import types
- >>> m = types.ModuleType('abc','docstring')
- >>> m
- <module 'abc' (built-in)>
- >>> m.__doc__
- 'docstring'
- \end{verbatim}
  
! \item 
! A new warning, \exception{PendingDeprecationWarning} was added to
! indicate features which are in the process of being
! deprecated.  The warning will \emph{not} be printed by default.  To
! check for use of features that will be deprecated in the future,
! supply \programopt{-Walways::PendingDeprecationWarning::} on the
! command line or use \function{warnings.filterwarnings()}.
  
! \item One minor but far-reaching change is that the names of extension
! types defined by the modules included with Python now contain the
! module and a \samp{.} in front of the type name.  For example, in
! Python 2.2, if you created a socket and printed its
! \member{__class__}, you'd get this output:
  
! \begin{verbatim}
! >>> s = socket.socket()
! >>> s.__class__
! <type 'socket'>
! \end{verbatim}
  
! In 2.3, you get this:
! \begin{verbatim}
! >>> s.__class__
! <type '_socket.socket'>
! \end{verbatim}
  
  \end{itemize}
  
  %======================================================================
--- 662,698 ----
     can't create \class{basestring} instances.
  
! \item Interned strings are no longer immortal.  Interned will now be
! garbage-collected in the usual way when the only reference to them is
! from the internal dictionary of interned strings.  (Implemented by
! Oren Tirosh.)
  
! \end{itemize}
  
  
! \subsection{Optimizations}
  
! \begin{itemize}
  
! \item The \method{sort()} method of list objects has been extensively
! rewritten by Tim Peters, and the implementation is significantly
! faster.
  
! \item Multiplication of large long integers is now much faster thanks
! to an implementation of Karatsuba multiplication, an algorithm that
! scales better than the O(n*n) required for the grade-school
! multiplication algorithm.  (Original patch by Christopher A. Craig,
! and significantly reworked by Tim Peters.)
! 
! \item The \code{SET_LINENO} opcode is now gone.  This may provide a
! small speed increase, subject to your compiler's idiosyncrasies.
! (Removed by Michael Hudson.)
! 
! \item A number of small rearrangements have been made in various
! hotspots to improve performance, inlining a function here, removing
! some code there.  (Implemented mostly by GvR, but lots of people have
! contributed to one change or another.)
  
  \end{itemize}
+ 
  
  %======================================================================