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Part of SF patch #1513870 (the still relevant part) -- add reduce() to

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functools, and adjust docs etc.
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Guido van Rossum 2006-08-26 20:49:04 +00:00
parent 6a2a2a0832
commit 0919a1a07b
11 changed files with 168 additions and 78 deletions
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13
Doc/lib/libfunctools.tex
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@ -51,6 +51,19 @@ two:
\end{verbatim}
\end{funcdesc}
\begin{funcdesc}{reduce}{function, sequence\optional{, initializer}}
Apply \var{function} of two arguments cumulatively to the items of
\var{sequence}, from left to right, so as to reduce the sequence to
a single value. For example, \code{reduce(lambda x, y: x+y, [1, 2,
3, 4, 5])} calculates \code{((((1+2)+3)+4)+5)}. The left argument,
\var{x}, is the accumulated value and the right argument, \var{y},
is the update value from the \var{sequence}. If the optional
\var{initializer} is present, it is placed before the items of the
sequence in the calculation, and serves as a default when the
sequence is empty. If \var{initializer} is not given and
\var{sequence} contains only one item, the first item is returned.
\end{funcdesc}
\begin{funcdesc}{update_wrapper}
{wrapper, wrapped\optional{, assigned}\optional{, updated}}
Update a wrapper function to look like the wrapped function. The optional