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diff --git a/Doc/lib/libuserdict.tex b/Doc/lib/libuserdict.tex deleted file mode 100644 index 0bb57c8..0000000 --- a/Doc/lib/libuserdict.tex +++ /dev/null @@ -1,181 +0,0 @@ -\section{\module{UserDict} --- - Class wrapper for dictionary objects} - -\declaremodule{standard}{UserDict} -\modulesynopsis{Class wrapper for dictionary objects.} - - -The module defines a mixin, \class{DictMixin}, 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). - -This also module defines a class, \class{UserDict}, that acts as a wrapper -around dictionary objects. The need for this class has been largely -supplanted by the ability to subclass directly from \class{dict} (a feature -that became available starting with Python version 2.2). Prior to the -introduction of \class{dict}, the \class{UserDict} class was used to -create dictionary-like sub-classes that obtained new behaviors by overriding -existing methods or adding new ones. - -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 contents are kept -in a regular dictionary, which is accessible via the \member{data} -attribute of \class{UserDict} instances. If \var{initialdata} is -provided, \member{data} is initialized with its contents; note that a -reference to \var{initialdata} will not be kept, allowing it be used -for other purposes. \note{For backward compatibility, instances of -\class{UserDict} are not iterable.} -\end{classdesc} - -\begin{classdesc}{IterableUserDict}{\optional{initialdata}} -Subclass of \class{UserDict} that supports direct iteration (e.g. -\code{for key in myDict}). -\end{classdesc} - -In addition to supporting the methods and operations of mappings (see -section \ref{typesmapping}), \class{UserDict} and -\class{IterableUserDict} instances provide the following attribute: - -\begin{memberdesc}{data} -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, -defining all but \method{__delitem__} will preclude only \method{pop} -and \method{popitem} from the full interface. - -In addition to the four base methods, progressively more efficiency -comes with defining \method{__contains__()}, \method{__iter__()}, and -\method{iteritems()}. - -Since the mixin has no knowledge of the subclass constructor, it -does not define \method{__init__()} or \method{copy()}. -\end{classdesc} - - -\section{\module{UserList} --- - Class wrapper for list objects} - -\declaremodule{standard}{UserList} -\modulesynopsis{Class wrapper for list objects.} - - -\note{This module is available for backward compatibility only. If -you are writing code that does not need to work with versions of -Python earlier than Python 2.2, please consider subclassing directly -from the built-in \class{list} type.} - -This module defines a class that acts as a wrapper around -list objects. It is a useful base class for -your own list-like classes, which can inherit from -them and override existing methods or add new ones. In this way one -can add new behaviors to lists. - -The \module{UserList} module defines the \class{UserList} class: - -\begin{classdesc}{UserList}{\optional{list}} -Class that simulates a list. The instance's -contents are kept in a regular list, which is accessible via the -\member{data} attribute of \class{UserList} instances. The instance's -contents are initially set to a copy of \var{list}, defaulting to the -empty list \code{[]}. \var{list} can be either a regular Python list, -or an instance of \class{UserList} (or a subclass). -\end{classdesc} - -In addition to supporting the methods and operations of mutable -sequences (see section \ref{typesseq}), \class{UserList} instances -provide the following attribute: - -\begin{memberdesc}{data} -A real Python list object used to store the contents of the -\class{UserList} class. -\end{memberdesc} - -\strong{Subclassing requirements:} -Subclasses of \class{UserList} are expect to offer a constructor which -can be called with either no arguments or one argument. List -operations which return a new sequence attempt to create an instance -of the actual implementation class. To do so, it assumes that the -constructor can be called with a single parameter, which is a sequence -object used as a data source. - -If a derived class does not wish to comply with this requirement, all -of the special methods supported by this class will need to be -overridden; please consult the sources for information about the -methods which need to be provided in that case. - -\versionchanged[Python versions 1.5.2 and 1.6 also required that the - constructor be callable with no parameters, and offer - a mutable \member{data} attribute. Earlier versions - of Python did not attempt to create instances of the - derived class]{2.0} - - -\section{\module{UserString} --- - Class wrapper for string objects} - -\declaremodule{standard}{UserString} -\modulesynopsis{Class wrapper for string objects.} -\moduleauthor{Peter Funk}{pf@artcom-gmbh.de} -\sectionauthor{Peter Funk}{pf@artcom-gmbh.de} - -\note{This \class{UserString} class from this module is available for -backward compatibility only. If you are writing code that does not -need to work with versions of Python earlier than Python 2.2, please -consider subclassing directly from the built-in \class{str} type -instead of using \class{UserString} (there is no built-in equivalent -to \class{MutableString}).} - -This module defines a class that acts as a wrapper around string -objects. It is a useful base class for your own string-like classes, -which can inherit from them and override existing methods or add new -ones. In this way one can add new behaviors to strings. - -It should be noted that these classes are highly inefficient compared -to real string or Unicode objects; this is especially the case for -\class{MutableString}. - -The \module{UserString} module defines the following classes: - -\begin{classdesc}{UserString}{\optional{sequence}} -Class that simulates a string or a Unicode string -object. The instance's content is kept in a regular string or Unicode -string object, which is accessible via the \member{data} attribute of -\class{UserString} instances. The instance's contents are initially -set to a copy of \var{sequence}. \var{sequence} can be either a -regular Python string or Unicode string, an instance of -\class{UserString} (or a subclass) or an arbitrary sequence which can -be converted into a string using the built-in \function{str()} function. -\end{classdesc} - -\begin{classdesc}{MutableString}{\optional{sequence}} -This class is derived from the \class{UserString} above and redefines -strings to be \emph{mutable}. Mutable strings can't be used as -dictionary keys, because dictionaries require \emph{immutable} objects as -keys. The main intention of this class is to serve as an educational -example for inheritance and necessity to remove (override) the -\method{__hash__()} method in order to trap attempts to use a -mutable object as dictionary key, which would be otherwise very -error prone and hard to track down. -\end{classdesc} - -In addition to supporting the methods and operations of string and -Unicode objects (see section \ref{string-methods}, ``String -Methods''), \class{UserString} instances provide the following -attribute: - -\begin{memberdesc}{data} -A real Python string or Unicode object used to store the content of the -\class{UserString} class. -\end{memberdesc} |