From: Fred Drake Date: Tue, 19 Sep 2000 18:21:25 +0000 (+0000) Subject: Moshe Zadka : X-Git-Tag: v2.0b2~195 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=8d27f898b2a601039859cc12e105f567e5d0e946;p=python Moshe Zadka : Document the __contains__() method. (Patch slightly modified by FLD.) This closes SourceForge patch #101387. --- diff --git a/Doc/ref/ref3.tex b/Doc/ref/ref3.tex index 1b072962f9..53e919fdd9 100644 --- a/Doc/ref/ref3.tex +++ b/Doc/ref/ref3.tex @@ -1172,6 +1172,16 @@ involving extended slice notation, or in absence of the slice methods, \method{__getitem__()}, \method{__setitem__()} or \method{__delitem__()} is called with a slice object as argument. +The membership test operators (\keyword{in} and \keyword{not in}) are +normally implemented as iteration loop through the sequence. However, +sequence objects can supply the following special method with a more +efficient implementation: + +\begin{methoddesc}[sequence object]{__contains__}{self, item} +Called to implement membership test operators. Should return true if +\var{item} is in \var{self}, false otherwise. +\end{methoddesc} + \subsection{Emulating numeric types\label{numeric-types}}