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Diffstat (limited to 'Doc/lib/libuserdict.tex')
| -rw-r--r-- | Doc/lib/libuserdict.tex | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/Doc/lib/libuserdict.tex b/Doc/lib/libuserdict.tex index d665686..e01c546 100644 --- a/Doc/lib/libuserdict.tex +++ b/Doc/lib/libuserdict.tex @@ -15,7 +15,13 @@ your own dictionary-like classes, which can inherit from them and override existing methods or add new ones. In this way one can add new behaviors to dictionaries. -The \module{UserDict} module defines the \class{UserDict} class: +The module also defines a mixin defining all dictionary methods for +classes that already have a minimum mapping interface. This greatly +simplifies writing classes that need to be substitutable for +dictionaries (such as the shelve module). + +The \module{UserDict} module defines the \class{UserDict} class +and \class{DictMixin}: \begin{classdesc}{UserDict}{\optional{initialdata}} Class that simulates a dictionary. The instance's @@ -35,6 +41,23 @@ A real dictionary used to store the contents of the \class{UserDict} class. \end{memberdesc} +\begin{classdesc}{DictMixin}{} +Mixin defining all dictionary methods for classes that already have +a minimum dictionary interface including\method{__getitem__}, +\method{__setitem__}, \method{__delitem__}, and \method{keys}. + +This mixin should be used as a superclass. Adding each of the +above methods adds progressively more functionality. For instance, +the absence of \method{__delitem__} precludes only \method{pop} +and \method{popitem}. + +While the four methods listed above are sufficient to support the +entire dictionary interface, progessively more efficiency comes +with defining \method{__contains__}, \method{__iter__}, and +\method{iteritems}. + +\end{classdesc} + \section{\module{UserList} --- Class wrapper for list objects} |