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diff --git a/libstdc++-v3/docs/html/ext/pb_assoc/concepts.html b/libstdc++-v3/docs/html/ext/pb_assoc/concepts.html deleted file mode 100644 index cd7295891e8..00000000000 --- a/libstdc++-v3/docs/html/ext/pb_assoc/concepts.html +++ /dev/null @@ -1,124 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> -<html> -<head> -<title>Concepts</title> -<meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1"> -<meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5"> -</head> -<body bgcolor = "white"> -<h1>Concepts</h1> - -<p> -Following are some concepts used throughout the documentation. -</p> - -<ol> - <li><a href = "#concepts_null_policies">Null Policy Classes</a></li> - <li><a href = "#concepts_find_and_range_iterators">Find and Range Iterators</a></li> - <li><a href = "#concepts_mapping_levels">Mapping Levels</a></li> -</ol> - -<h2><a name = "concepts_null_policies">Null Policy Classes</a></h2> - -<p> - Associative containers are typically parameterized by various policies. -For example, a hash-based associative -container is parameterized by a hash-functor, transforming each key into an non-negative numerical type. Each such value is then further mapped into a position within the table. -The mapping of a key into a position within the table is therefore a two-step process. -</p> - -<p> -In some -cases, instantiations are <i>redundant</i>. For example, when the keys are integers, it is possible to use a <i>redundant</i> -hash policy, which transforms each key into its value. -</p> - -<p> - In some other cases, these policies are <i>irrelevent</i>. For example, -a hash-based associative container might transform keys into positions within -a table by a different method than the two-step method described above. In such a case, the hash functor is simply irrelevent. -</p> - -<p> - <tt>pb_assoc</tt> uses special pre-defined "null policies" classes -for these cases. Some null policies in <tt>pb_assoc</tt> -are: -</p> -<ol> - <li <a href = "null_data_type.html"><tt>null_data_type</tt></a></li> - <li><a href = "null_node_updator.html"><tt>null_node_updator</tt></a></li> - <li><a href = "null_hash_fn.html"><tt>null_hash_fn</tt></a></li> - <li><a href = "null_probe_fn.html"><tt>null_probe_fn</tt></a></li> -</ol> - -<p> -A "set" in <tt>pb_assoc</tt> is an associative container with its <tt>Data_Parameter</tt> instantiated by -<a href = "null_data_type.html"><tt>null_data_type</tt></a>. -<a href = "tree_based_containers.html#node_invariants.html">Tree-Based Containers::Node Invariants</a> -explains another case where a null policy is needed. -</p> - - - -<h2><a name = "concepts_find_and_range_iterators">Find and Range Methods and Iterators</a></h2> - -<p> - Associative containers allow access to their elements via iterators. <i>E.g.</i>, -<tt>find</tt> returns an iterator to an element with a given key and -<tt>begin</tt> returns an iterator to the first element in the container. -</p> - -<p> -In general, there are two types of methods: <i>find types</i>, and <i>range types</i>. - Find-type -methods return iterators corresponding to elements which have been found in some sense, as -the container searched for them in order to access them (<i>i.e.</i>, via the -<tt>find</tt> method) or searched for their location in order to insert them -(<i>i.e.</i>, via the <tt>insert</tt> method). Range-type methods return iterators -which can be used to traverse the range of all stored elements, (<i>i.e.</i>, via the -<tt>begin</tt> and <tt>end</tt> methods). -</p> - -<p>Correspondingly, in <tt>pb_assoc</tt> there are two types of iterators: <i>find type</i> -iterators are returned by find methods, and range iterators are returned by range methods. For example, -if <tt>T</tt> is any associative container with integer keys, and <tt>t</tt> -is a container of type <tt>T</tt>, -then the following snippet is valid: -</p> - -<pre> -<b>typename</b> T::find_iterator it0 = t.find(3); -<b>typename</b> T::const_find_iterator it0 = t.find(3); - -<b>typename</b> T::iterator it0 = t.begin(); -<b>typename</b> T::const_iterator it0 = t.begin(); -</pre> - - -<p> - This is motivated and explained further in -<a href = "ds_gen.html#find_range">Data-Structure Genericity::Find-Type and Range-Type Methods and Iterators</a>, which also explains the relationship between find-type and range-type iterators. -</p> - -<h2><a href = "#concepts_mapping_levels">Mapping Levels</a></h2> - -<p> - In <tt>pb_assoc</tt> "multimaps" are -"maps" of "sets". While this design allows efficient -operations, it makes for cumbersome use at points. For example a -"multimap" of integers to characters does not -directly support <tt>inser(std::make_pair(2, 'b')</tt>, since 2 is mapped -to a "set" of characters, and not to a character. -</p> - -<p> - Consequently, <tt>pb_assoc</tt> contains a rebind-like mechanism so that -containers can support such operations. To dispel ambiguity, container types are -assigned mapping levels. "Maps" and "sets" have -a mapping level 1, since they use a single association level. The "multimap" -above has a mapping level 2, since it uses two association levels: one for integers, and one for characters. The rebind mechanism can be used to alter the association level. This is described in -<a href = "ms_gen.html">Mapping Semantics</a>. -</p> - -</body> -</html> |