diff --git a/Doc/whatsnew/whatsnew25.tex b/Doc/whatsnew/whatsnew25.tex index ba479dbf8d7..c26be0a7d60 100644 --- a/Doc/whatsnew/whatsnew25.tex +++ b/Doc/whatsnew/whatsnew25.tex @@ -37,7 +37,24 @@ Here are all of the changes that Python 2.5 makes to the core Python language. \begin{itemize} -\item TBD + +\item The \function{min()} and \function{max()} built-in functions +gained a \code{key} keyword argument analogous to the \code{key} +argument for \function{sort()}. This argument supplies a function +that takes a single argument and is called for every value in the list; +\function{min()}/\function{max()} will return the element with the +smallest/largest return value from this function. +For example, to find the longest string in a list, you can do: + +\begin{verbatim} +L = ['medium', 'longest', 'short'] +# Prints 'longest' +print max(L, key=len) +# Prints 'short', because lexicographically 'short' has the largest value +print max(L) +\end{verbatim} + +(Contributed by Steven Bethard and Raymond Hettinger.) \end{itemize}