From 0c4755935251c2231086fe6636ab2104b7a8edc6 Mon Sep 17 00:00:00 2001 From: Fred Drake Date: Thu, 7 Dec 2000 04:49:34 +0000 Subject: Added a note that objects which emulate built-in types should only implement as many of the relevant methods as make sense for the particular information being modelled. --- Doc/ref/ref3.tex | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Doc/ref/ref3.tex b/Doc/ref/ref3.tex index 905a001..0222110 100644 --- a/Doc/ref/ref3.tex +++ b/Doc/ref/ref3.tex @@ -841,6 +841,13 @@ a list object, \code{x.__getitem__(i)} is not equivalent to operation raise an exception when no appropriate method is defined. \withsubitem{(mapping object method)}{\ttindex{__getitem__()}} +When implementing a class that emulates any built-in type, it is +important that the emulation only be implemented to the degree that it +makes sense for the object being modelled. For example, some +sequences may work well with retrieval of individual elements, but +extracting a slice may not make sense. (One example of this is the +\class{NodeList} interface in the W3C's Document Object Model.) + \subsection{Basic customization\label{customization}} -- cgit v0.12