forked from boostorg/range
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[SVN r24315]
This commit is contained in:
Thorsten Jørgen Ottosen
@ -1,112 +1,128 @@
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><title> Boost.Range External Range Implementation </title><meta http-equiv="Content-Type"content="text/html; charset=iso-8859-1"></head> <body><table ><tr ><td ><img src="cboost.gif" width="100%" border="0"></td><td ><h1 ><br>Boost.Range External Range Implementation </h1></td></tr></table><ul ><li ><a href="#Introduction" >Introduction</a></li><li ><a href="#Reference" >Reference</a></li><ul ><li ><a href="#Synopsis" >Synopsis</a></li><li ><a href="#Library headers" >Library headers</a></li><li ><a href="#Semantics" >Semantics</a></li></ul><li ><a href="#Examples" >Examples</a></li><li ><a href="#Portability" >Portability</a></li><li ><a href="#FAQ" >FAQ</a></li><li ><a href="#History" >History</a></li></ul><hr size="1" ><h2 >Introduction</h2><a name="Introduction" ></a><p >This library makes it possible to treat different types as if they have
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implemented a subset of the container requirements
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(see §23.1of the C++ standard). Formally, that subset is defined by
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the <a href="Collection.htm" target="_self" >CollectionConcept.</a>
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The subset deals mostly with
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iterator returning functions and nested <code >typedef</code>s.
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The main goal is to treat built-in arrays, standard containers,
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pairs of iterators and some iterators uniformly. Formally, this library is an implementation
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of the <a href="#ExternalCollectionConcept" >ExternalCollectionConcept</a> (see also this explanation of <a href="external_concepts.html" target="_self" >External Concepts</a> ).</p><p >The main advantages are <ul ><li >safe use of built-in arrays</li><li >simpler implementation of generic container algorithms</li><li >more flexible client code</li><li >correct handling of null-terminated strings</li></ul></p><p >Below are given a small example (the complete example can be found <a href="../test/algorithm_example.cpp" target="_self" >here</a> ):<pre >
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//
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// Example: extracting bounds in generic algorithms
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//
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template< typename ExternalCollection, typename T >
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inline typename boost::iterator_of<ExternalCollection>::type
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find( ExternalCollection& c, const T& value )
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{
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return std::find( boost::begin( c ), boost::end( c ), value );
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}
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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<html>
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<head>
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<title>Boost.Range Range Implementation </title>
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<meta http-equiv="Content-Type"content="text/html; charset=iso-8859-1">
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</head>
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template< typename ExternalCollection, typename T >
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inline typename boost::const_iterator_of<ExternalCollection>::type
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find( const ExternalCollection& c, const T& value )
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{
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return std::find( boost::begin( c ), boost::end( c ), value );
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}
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//
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// replace first value and return its index
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//
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template< typename EC, typename T >
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inline typename boost::size_type_of< EC >::type
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my_generic_replace( EC& c, const T& value, const T& replacement )
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{
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typename boost::const_iterator_of<EC>::type found = find( c, value );
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*found = replacement;
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return std::distance( boost::begin( c ), found );
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}
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//
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// usage
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//
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std::vector<int> my_vector;
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typedef vector<int>::iterator iterator;
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std::pair<iterator,iterator> my_view( my_vector.begin(), my_vector.begin() + N );
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char str[] = "a string";
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// ...
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std::cout << my_generic_replace( my_vector, 4, 2 )
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<< my_generic_replace( my_view, 4, 2 )
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<< my_generic_replace( str, 'a', 'b' );
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</pre>By using the free-standing functions and type-generators, the code automatically
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works for all the types supported by this library. Notice that we have to provide
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two version of <code >find()</code> since we cannot
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forward a non-const rvalue with reference arguments (see this article about <a href="http://std.dkuug.dk/jtc1/sc22/wg21/docs/papers/2002/n1385.htm" target="_self" >The Forwarding Problem</a> ).</p><hr size="1" ><h2 >Reference</h2><a name="Reference" ></a><p ><pre >#include <boost/collection_traits.hpp></pre></p><p >Five types of objects are currently supported by the library:<ul ><li >standard containers</li><li >built-in arrays</li><li >null terminated strings (this includes <code >char[]</code>,<code >wchar_t[]</code>,<code >char*</code>, and <code >wchar_t*</code>)</li><li ><code >std::pair<iterator,iterator></code></li><li >iterators which when default constructed denotes the end of the range</li></ul>It is worth noticing that some functionality requires partial template specialization, in particular,
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full array support does (remark: this is a very small problem since one would use <code>boost::array<></code>
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anyway). Also note that arrays and pointers of <code >char</code> or <code >whar_t</code> are treated special because of their use in string algorithms.</p><h3 >ExternalCollectionConcept</h3><a name="ExternalCollectionConcept" ></a><p >The concept is defined by the type-generators and the
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functions below. Even though these functions are defined in
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namespace <code>boost</code>, there is no such general requirement, that is,
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if one wants to extend the list of supported types, it can be done in any
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namespace.</p><h3 >Synopsis</h3><a name="Synopsis" ></a><p ><pre>
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namespace boost
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<body>
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<table >
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<tr >
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<td ><img src="cboost.gif" width="100%" border="0"></td>
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<td ><h1 ><br>
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Boost.Range </h1></td>
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</tr>
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</table>
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<h2>Range and ReversibleRange Implementation</h2>
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<ul >
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<li>
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<a href="#overview">Overview</a>
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<li >
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<a href="#Synopsis" >Synopsis</a>
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</li>
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<li >
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<a href="#Semantics" >Semantics</a>
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</li>
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<li >
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<a href="#Examples" >Examples</a>
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</li>
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</ul>
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<hr size="1" >
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<h3>Overview</h3>
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<p>
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Five types of objects are currently supported by the library:
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<ul >
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<li >
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standard containers
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</li>
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<li >
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built-in arrays
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</li>
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<li >
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null terminated strings (this includes <code >char[]</code>,<code >wchar_t[]</code>,
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<code >char*</code>, and <code >wchar_t*</code>)
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</li>
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<li >
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<code >std::pair<iterator,iterator></code>
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</li>
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<li >
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iterators which when default constructed denotes the end of the range
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</li>
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</ul>
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It is worth noticing that some functionality requires partial template
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specialization, in particular, full array support does (remark: this is a very
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small problem since one would use <code>boost::array<></code> anyway). Also note
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that arrays and pointers of <code >char</code> or <code >whar_t</code> are
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treated special because of their use in string algorithms.
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</p>
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<h3 >ExternalCollectionConcept</h3><a name="ExternalCollectionConcept" ></a>
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<p >
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The concept is defined by the type-generators and the functions below. Even
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though these functions are defined in namespace <code>boost</code>, there is no
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such general requirement, that is, if one wants to extend the list of supported
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types, it can be done in any namespace.
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</p>
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<h3 >Synopsis</h3><a name="Synopsis" ></a>
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<p >
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<pre>
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namespace boost
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{
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//
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//
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// type generators
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//
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//
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template< typename EC >
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template< typename EC >
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struct <a href="#value_type_of" >value_type_of</a>
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{
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typedef ... type; // type of stored objects
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typedef ... type; // type of stored objects
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};
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template< typename EC >
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struct <a href="#iterator_of" >iterator_of</a>
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template< typename EC >
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struct <a href="#iterator_of" >iterator_of</a>
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{
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typedef ... type; // iterator over stored objects
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};
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template< typename EC >
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struct <a href="#const_iterator_of" >const_iterator_of</a>
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template< typename EC >
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struct <a href="#const_iterator_of" >const_iterator_of</a>
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{
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typedef ... type; // iterator over immutable stored objects
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typedef ... type; // iterator over immutable stored objects
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};
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template< typename EC >
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template< typename EC >
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struct <a href="#difference_type_of" >difference_type_of</a>
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{
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typedef ... type;
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typedef ... type;
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BOOST_STATIC_ASSERT( boost::is_signed< type >::value );
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//
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// remark: if std::iterator_traits<> works for the type, this assertion must hold
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// remark: if std::iterator_traits<> works for the type, this assertion must
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hold
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//
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BOOST_STATIC_ASSERT( boost::is_same< type, std::iterator_traits< typename
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<a href="#iterator_of" >iterator_of</a>< EC >::type >::difference_type>::value );
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BOOST_STATIC_ASSERT( boost::is_same< type, std::iterator_traits< typename
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<a href="#iterator_of" >iterator_of</a>< EC >::type >::difference_type>::value );
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};
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template< typename EC >
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template< typename EC >
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struct <a href="#size_type_of" >size_type_of</a>
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{
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typedef ... type;
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BOOST_STATIC_ASSERT( boost::is_unsigned< type >::value );
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BOOST_STATIC_ASSERT( sizeof( type ) >= sizeof( <a href="#difference_type_of" >difference_type_of</a>< EC >::type ) );
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BOOST_STATIC_ASSERT( sizeof( type ) >= sizeof( <a href="#difference_type_of" >
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difference_type_of</a>< EC >::type ) );
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};
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template< typename EC >
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struct <a href="#result_iterator_of" >result_iterator_of</a>
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template< typename EC >
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struct <a href="#result_iterator_of" >result_iterator_of</a>
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{
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typedef ... type;
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// <a href="#iterator_of" >iterator_of</a>< EC >::type if EC is non-const, <a href="#const_iterator_of" >const_iterator_of</a>< EC >::type otherwise
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typedef ... type;
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// <a href="#iterator_of" >iterator_of</a>< EC >::type if EC is non-const, <a href="#const_iterator_of" >
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const_iterator_of</a>< EC >::type otherwise
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};
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//
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@ -115,15 +131,15 @@
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template< typename EC >
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inline typename iterator_of<EC>::type
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<a href="#begin" >begin</a>( EC& c );
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<a href="#begin" >begin</a>( EC& c );
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template< typename EC >
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inline typename const_iterator_of< EC >::type
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<a href="#begin" >begin</a>( const EC& c );
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<a href="#begin" >begin</a>( const EC& c );
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template< typename EC >
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inline typename iterator_of< EC >::type
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<a href="#end" >end</a>( EC& c );
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<a href="#end" >end</a>( EC& c );
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template< typename EC >
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inline typename const_iterator_of< EC >::type
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@ -131,38 +147,230 @@
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template< typename EC >
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inline bool
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<a href="#empty" >empty</a>( const EC& c );
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<a href="#empty" >empty</a>( const EC& c );
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template< typename EC >
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inline typename size_type_of< EC >::type
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<a href="#size" >size</a>( const EC& c );
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} // namespace 'boost' </pre></p><h3 >Library headers</h3><a name="Library headers" ></a><table cellpadding=5 border=1 > <tr ><th >Header</th><th >Includes</th></tr><tr ><td ><code ><boost/collection_traits.hpp></code></td><td >everything</td></tr><tr ><td ><code ><boost/collection_traits/types.hpp></code></td><td >every type-generator</td></tr><tr ><td ><code ><boost/collection_traits/functions.hpp></code></td><td >every function</td></tr><tr ><td ><code ><boost/collection_traits/value_type.hpp></code></td><td ><a href="#value_type_of" >value_type_of</a></td></tr><tr ><td ><code ><boost/collection_traits/iterator.hpp></code></td><td ><a href="#iterator_of" >iterator_of</a></td></tr><tr ><td ><code ><boost/collection_traits/const_iterator.hpp></code></td><td ><a href="#const_iterator_of" >const_iterator_of</a></td></tr><tr ><td ><code ><boost/collection_traits/difference_type.hpp></code></td><td ><a href="#difference_type_of" >difference_type_of</a></td></tr><tr ><td ><code ><boost/collection_traits/size_type.hpp></code></td><td ><a href="#size_type_of" >size_type_of</a></td></tr><tr ><td ><code ><boost/collection_traits/result_iterator.hpp></code></td><td ><a href="#result_iterator_of" >result_iterator_of</a></td></tr><tr ><td ><code ><boost/collection_traits/begin.hpp></code></td><td ><a href="#begin" >begin</a></td></tr><tr ><td ><code ><boost/collection_traits/end.hpp></code></td><td ><a href="#end" >end</a></td></tr><tr ><td ><code ><boost/collection_traits/empty.hpp></code></td><td ><a href="#empty" >empty</a></td></tr><tr ><td ><code ><boost/collection_traits/size.hpp></code></td><td ><a href="#size" >size</a></td></tr> </table><br><h3 >Semantics</h3><a name="Semantics" ></a><p >In the table <code >C</code> is a type that conforms to the ExternalCollectionConcept and <code >c</code> is an object of that type.<code > SC</code> will denote a standard
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container, <code > T[sz]</code> will denote an array of type <code >T</code> of size <code >sz</code>, <code >P</code> will denote <code >std::pair<></code>, <code > I</code> means an iterator which default construction
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denotes the end of the range and <code >sc,t,p,i</code> are objects of these types,
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respectively. Special cases for <code >char*</code> and <code >wchar_t*</code> are described explicitly. </p><table border=1 cellpadding=5 > <tr ><th >Expression</th><th >Return type</th><th >Complexity</th></tr><tr ><a name="value_type_of" ></a><td ><code >value_type_of<C>::type</code></td><td ><code >SC::value_type</code><br><code >T</code><br><code >std::iterator_traits<P::first_type>::value_type</code><br><code >std::iterator_traits<I>::value_type</code></td><td >compile time</td></tr><tr ><a name="iterator_of" ></a><td ><code >iterator_of<C>::type</code></td><td ><code >SC::iterator</code><br><code >T*</code><br><code >P::first_type</code><br><code >I</code></td><td >compile time</td></tr><tr ><a name="const_iterator_of" ></a><td ><code >const_iterator_of<C>::type</code></td><td ><code >SC::const_iterator</code><br><code >const T*</code><br><code >P::first_type</code><br><code >I</code></td><td >compile time</td></tr><tr ><a name="difference_type_of" ></a><td ><code >difference_type_of<C>::type</code></td><td ><code >SC::difference_type</code><br><code >std::ptrdiff_t</code><br><code >std::iterator_traits<P::first_type>::difference_type</code><br><code >std::iterator_traits<I>::difference_type</code></td><td >compile time</td></tr><tr ><a name="size_type_of" ></a><td ><code >size_type_of<C>::type</code></td><td ><code >SC::size_type</code><br><code >std::size_t</code><br><code >std::size_t</code><br><code >std::size_t</code></td><td >compile time</td></tr><tr ><a name="result_iterator_of" ></a><td ><code >result_iterator_of<C>::type</code></td><td ><code >const_iterator_of<C>::type</code> if <code >C</code> is <code >const</code><br><code >iterator_of<C>::type</code> otherwise </td><td >compile time</td></tr> </table> <br> <table border=1 cellpadding=5 > <tr ><th >Expression</th><th >Return type</th><th >Effects</th><th >Complexity</th></tr><tr ><a name="begin" ></a><td ><code >begin( c )</code></td><td ><code >result_iterator_of<C>::type</code></td><td ><code >sc.begin()</code><br><code >t</code><br><code >p.first</code><br><code >i</code></td><td >constant time</td></tr><tr ><a name="end" ></a><td ><code >end( c )</code></td><td ><code >result_iterator_of<C>::type</code></td><td ><code >sc.end()</code><br><code >t + std::char_traits<C>::length( t )</code> if <code >C</code> is <code >char*</code> or <code >wchar_t*</code><br><code >t + sz - 1</code> if <code >C</code> is <code >char[sz]</code> or <code >wchar_t[sz]</code><br><code >t + sz</code> otherwise <br><code >p.second</code><br><code >I()</code></td><td >linear if <code >C</code> is <code >char*</code> or <code >wchar_t*</code><br>constant time otherwise</td></tr><tr ><a name="empty" ></a><td ><code >empty( c )</code></td><td >Convertible to <code >bool</code></td><td ><code >sc.empty()</code><br><code >size( t ) == 0</code><br><code >p.first == p.second</code><br><code >begin( i ) == end( i )</code></td><td >linear if <code >C</code> is <code >char*</code> or <code >wchar_t*</code><br>constant time otherwise<br></td></tr><tr ><a name="size" ></a><td ><code >size( c )</code></td><td ><code >size_type_of<C>::type</code></td><td ><code >sc.size()</code><br><code >end( t ) - begin( t )</code><br><code >distance( p.first, p.second )</code><br><code >not available for iterators</code></td><td >linear if <code >C</code> is <code >char*</code> or <code >wchar_t*</code><br> or if <code >std::distance()</code> is linear <br>constant time otherwise</td></tr> </table><p >Please note that <code >char*</code>,<code >whar_t*</code>,<code >char[]</code>, and <code >wchar_t[]</code> behaves differently from
|
||||
normal arrays only for <code >size()</code> and <code >end()</code>.
|
||||
Note that the null pointer is allowed as an argument in these cases.</p><br><hr size="1" ><h2 >Examples</h2><a name="Examples" ></a><p >Some examples are given in the accompanying test
|
||||
files:</p><ul ><li > <a href="../test/iterator.cpp" target="_self" ><code >iterator.cpp</code></a> </li> shows how to implement a container version of <code >std::copy()</code> that works with <code >std::ifstream_iterator<>.</code><li > <a href="../test/string.cpp" target="_self" ><code >string.cpp</code></a> </li> shows how to implement a container version of <code >std::find()</code> that works with <code >char[],wchar_t[],char*,wchar_t*.</code><li > <a href="../test/algorithm_example.cpp" target="_self" ><code >algorithm_example.cpp</code></a> </li> shows the replace example from the introduction. </ul><hr size="1" ><h2 >Portability</h2><a name="Portability" ></a><p >Full support for built-in arrays require that the
|
||||
compiler supports class template partial specialization.</p><p >Notice that some compilers cannot do function template ordering
|
||||
properly. In that case one cannot rely of <code >result_iterator_of<></code> and a single function definition; instead one needs to supply
|
||||
a function overloaded for const and non-const arguments if it is required.</p><p >Full support for iterators like <code >std::istream_iterator<></code> depends very
|
||||
much on a conforming standard library.</p><p >Most of the tests have been run successfully on these compilers<ul ><li >vc7.1</li><li >gcc3.2</li><li >como4.3.0.1</li><li >bcc6</li></ul></p><hr size="1" ><h2 >FAQ</h2><a name="FAQ" ></a><ol ><li >Why is there no difference between <code >iterator_of<C>::type</code> and <code >const_iterator_of<C>::type</code> for <code >std::pair<iterator,iterator></code> or iterators which default construction denotes the end of the range?</li><p >In general it is not possible nor desirable to find a corresponding <code >const_iterator</code>. When it is possible to come up with
|
||||
one, the client might choose to
|
||||
construct a <code >std::pair<const_iterator,const_iterator></code> object. </p><li >Why does the traits not supply more types or more functions?<p >The traits class have been kept small because its current interface
|
||||
will serve most purposes. If and when a genuine need arises for
|
||||
more functionality, it can be implemented.</p></li><li >How should I implement generic algorithms for external collections?<p >One should always start with a generic algorithm that takes two iterators as input. Then use the
|
||||
collection traits to build handier versions on top of the base algorithm.</p></li></ol><hr size="1" ><h2 >History</h2><a name="History" ></a><p >The library have been under way for a long time. Dietmar K<>hl originally
|
||||
intended to submit an <code >array_traits<></code> class template which had most
|
||||
of the functionality present now, but only for arrays and standard containers.
|
||||
Meanwhile work on container algorithms
|
||||
in various context showed the need for handling pairs of iterators, and
|
||||
string libraries needed special treatment of character arrays.
|
||||
Thorsten Ottosen wrote everything from the ground up including the first
|
||||
work-around for missing partial template specialization. Pavol Droba helped to
|
||||
improve the work-around for handicapped compilers and the special character support.
|
||||
The naming scheme of type-generators was suggested by Peter Dimov. </p><hr size="1" ><p >© Thorsten Ottosen 2003-2004 (nesotto_AT_cs.auc.dk).
|
||||
Permission to copy, use, modify, sell and distribute this software is granted provided this copyright notice appears
|
||||
in all copies. This software is provided "as is" without express or implied warranty, and with no
|
||||
claim as to its suitability for any purpose.</p><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br></body></html>
|
||||
<!-- Copyright Dezide Aps 2003-2004 -->
|
||||
} // namespace 'boost' </pre>
|
||||
</p>
|
||||
|
||||
|
||||
<h3 >Semantics</h3><a name="Semantics" ></a>
|
||||
<p >
|
||||
In the table <code >C</code> is a type that conforms to the
|
||||
ExternalCollectionConcept and <code >c</code> is an object of that type.<code >
|
||||
SC</code>
|
||||
will denote a standard container, <code >T[sz]</code> will denote an array of
|
||||
type <code >T</code> of size <code >sz</code>, <code >P</code> will denote <code >
|
||||
std::pair<></code>,
|
||||
<code >I</code> means an iterator which default construction denotes the end of
|
||||
the range and <code >sc,t,p,i</code> are objects of these types, respectively.
|
||||
Special cases for <code >char*</code> and <code >wchar_t*</code> are described
|
||||
explicitly.
|
||||
</p>
|
||||
<table border="1" cellpadding="5" >
|
||||
<tr >
|
||||
<th >Expression</th>
|
||||
<th >Return type</th>
|
||||
<th >Complexity</th>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="value_type_of" ></a>
|
||||
<td ><code >value_type_of<C>::type</code></td>
|
||||
<td ><code >SC::value_type</code><br>
|
||||
<code >T</code><br>
|
||||
<code >std::iterator_traits<P::first_type>::value_type</code><br>
|
||||
<td >compile time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="iterator_of" ></a>
|
||||
<td ><code >iterator_of<C>::type</code></td>
|
||||
<td ><code >SC::iterator</code><br>
|
||||
<code >T*</code><br>
|
||||
<code >P::first_type</code><br>
|
||||
<td >compile time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="const_iterator_of" ></a>
|
||||
<td ><code >const_iterator_of<C>::type</code></td>
|
||||
<td ><code >SC::const_iterator</code><br>
|
||||
<code >const T*</code><br>
|
||||
<code >P::first_type</code><br>
|
||||
<td >compile time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="difference_type_of" ></a>
|
||||
<td ><code >difference_type_of<C>::type</code></td>
|
||||
<td ><code >SC::difference_type</code><br>
|
||||
<code >std::ptrdiff_t</code><br>
|
||||
<code >std::iterator_traits<P::first_type>:: difference_type</code><br>
|
||||
<td >compile time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="size_type_of" ></a>
|
||||
<td ><code >size_type_of<C>::type</code></td>
|
||||
<td ><code >SC::size_type</code><br>
|
||||
<code >std::size_t</code><br>
|
||||
<code >std::size_t</code><br>
|
||||
<td >compile time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="result_iterator_of" ></a>
|
||||
<td ><code >result_iterator_of<C>::type</code></td>
|
||||
<td ><code >const_iterator_of< C>::type</code> if <code >C</code> is <code >
|
||||
const</code>
|
||||
<br>
|
||||
<code >iterator_of<C>::type</code> otherwise </td>
|
||||
<td >compile time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="reverse_iterator_of" ></a>
|
||||
<td ><code >reverse_iterator_of<C>::type</code></td>
|
||||
<td ><code >boost::reverse_iterator< typename iterator_of<T>::type
|
||||
></code><br> <td >compile time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="const_reverse_iterator_of" ></a>
|
||||
<td ><code >const_reverse_iterator_of<C>::type</code></td>
|
||||
<td ><code >boost::reverse_iterator< typename const_iterator_of<T>::type ></code><br>
|
||||
<td >compile time</td>
|
||||
</tr> <tr >
|
||||
<a name="reverse_result_iterator_of" ></a>
|
||||
<td ><code >reverse_result_iterator_of<C>::type</code></td>
|
||||
<td ><code >boost::reverse_iterator< typename result_iterator_of<T>::
|
||||
type ></code>
|
||||
<td >compile time</td>
|
||||
</tr>
|
||||
|
||||
|
||||
</table>
|
||||
<br>
|
||||
<table border="1" cellpadding="5" >
|
||||
<tr >
|
||||
<th >Expression</th>
|
||||
<th >Return type</th>
|
||||
<th >Returns</th>
|
||||
<th >Complexity</th>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="begin" ></a>
|
||||
<td ><code >begin( c )</code></td>
|
||||
<td ><code >result_iterator_of<C>::type</code></td>
|
||||
<td ><code >sc.begin()</code><br>
|
||||
<code >t</code><br>
|
||||
<code >p.first</code><br>
|
||||
<td >constant time</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="end" ></a>
|
||||
<td ><code >end( c )</code></td>
|
||||
<td ><code >result_iterator_of<C>::type</code></td>
|
||||
<td ><code >sc.end()</code><br>
|
||||
<code >t + std::char_traits<C>::length( t )</code> if <code >C</code> is <code >
|
||||
char*</code>
|
||||
or <code >wchar_t*</code><br>
|
||||
<code >t + sz - 1</code> if <code >C</code> is <code >char[sz]</code> or <code >
|
||||
wchar_t[sz]</code>
|
||||
<br>
|
||||
<code >t + sz</code> otherwise <br>
|
||||
<code >p.second</code><br>
|
||||
<td >linear if <code >C</code> is <code >char*</code> or <code >wchar_t*</code>
|
||||
<br>
|
||||
constant time otherwise</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="empty" ></a>
|
||||
<td ><code >empty( c )</code></td>
|
||||
<td >Convertible to <code >bool</code></td>
|
||||
<td ><code >sc.empty()</code><br>
|
||||
<code >size( t ) == 0</code><br>
|
||||
<code >p.first == p.second</code><br>
|
||||
<td >linear if <code >C</code> is <code >char*</code> or <code >wchar_t*</code>
|
||||
<br>
|
||||
constant time otherwise<br>
|
||||
</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="size" ></a>
|
||||
<td ><code >size( c )</code></td>
|
||||
<td ><code >size_type_of<C>::type</code></td>
|
||||
<td ><code >sc.size()</code><br>
|
||||
<code >end( t ) - begin( t )</code><br>
|
||||
<code >distance( p. first, p.second )</code><br>
|
||||
<td >linear if <code >C</code> is <code >char*</code> or <code >wchar_t*</code>
|
||||
<br>
|
||||
or if <code >std::distance()</code> is linear <br>
|
||||
constant time otherwise</td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="rbegin" ></a>
|
||||
<td ><code >rbegin( c )</code></td>
|
||||
<td ><code >reverse_result_iterator_of<C>::type</code></td>
|
||||
<td ><code >reverse_result_iterator_of<C>::type( end( c ) )</code>
|
||||
<br>
|
||||
<td >same as <code>end()</code> </td>
|
||||
</tr>
|
||||
<tr >
|
||||
<a name="rend" ></a>
|
||||
<td ><code >rend( c )</code></td>
|
||||
<td ><code >reverse_result_iterator_of<C>::type</code></td>
|
||||
<td ><code >reverse_result_iterator_of<C>::type( begin( c ) )</code>
|
||||
<td > same as <code>begin()</code></td>
|
||||
</tr>
|
||||
|
||||
</table>
|
||||
|
||||
<p >
|
||||
Please note that <code >char*</code>,<code >whar_t*</code>,<code >char[]</code>,
|
||||
and <code >wchar_t[]</code> behaves differently from normal arrays only for <code >
|
||||
size()</code>
|
||||
and <code >end()</code>. Note that the null pointer is allowed as an argument
|
||||
in these cases.
|
||||
</p>
|
||||
|
||||
|
||||
<hr size="1" ><h2 >Examples</h2><a name="Examples" ></a>
|
||||
<p >
|
||||
Some examples are given in the accompanying test files:
|
||||
</p>
|
||||
<ul >
|
||||
<li >
|
||||
<a href="../test/iterator.cpp" target="_self" ><code >iterator.cpp</code></a>
|
||||
</li>
|
||||
shows how to implement a container version of <code >std::copy()</code> that
|
||||
works with <code >std::ifstream_iterator<>.</code>
|
||||
<li >
|
||||
<a href="../test/string.cpp" target="_self" ><code >string.cpp</code></a>
|
||||
</li>
|
||||
shows how to implement a container version of <code >std::find()</code> that
|
||||
works with <code >char[],wchar_t[],char*,wchar_t*.</code>
|
||||
<li >
|
||||
<a href="../test/algorithm_example.cpp" target="_self" ><code >algorithm_example.cpp</code></a>
|
||||
|
||||
</li>
|
||||
shows the replace example from the introduction.
|
||||
</ul>
|
||||
|
||||
<hr>
|
||||
<p>
|
||||
(C) Copyright Thorsten Ottosen 2003-2004
|
||||
</p>
|
||||
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
<br>
|
||||
|
||||
|
||||
</body>
|
||||
</html>
|
||||
|
||||
Reference in New Issue
Block a user