1 <?xml version=
"1.0" encoding=
"utf-8" ?>
2 <!DOCTYPE html PUBLIC
"-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
3 <html xmlns=
"http://www.w3.org/1999/xhtml" xml:
lang=
"en" lang=
"en">
5 <meta http-equiv=
"Content-Type" content=
"text/html; charset=utf-8" />
6 <meta name=
"generator" content=
"Docutils 0.7: http://docutils.sourceforge.net/" />
7 <title>The MPL Reference Manual: find_if
</title>
8 <link rel=
"stylesheet" href=
"../style.css" type=
"text/css" />
10 <body class=
"docframe refmanual">
11 <table class=
"header"><tr class=
"header"><td class=
"header-group navigation-bar"><span class=
"navigation-group"><a href=
"./find.html" class=
"navigation-link">Prev
</a> <a href=
"./contains.html" class=
"navigation-link">Next
</a></span><span class=
"navigation-group-separator"> |
</span><span class=
"navigation-group"><a href=
"./find.html" class=
"navigation-link">Back
</a> <a href=
"./contains.html" class=
"navigation-link">Along
</a></span><span class=
"navigation-group-separator"> |
</span><span class=
"navigation-group"><a href=
"./querying-algorithms.html" class=
"navigation-link">Up
</a> <a href=
"../refmanual.html" class=
"navigation-link">Home
</a></span><span class=
"navigation-group-separator"> |
</span><span class=
"navigation-group"><a href=
"./refmanual_toc.html" class=
"navigation-link">Full TOC
</a></span></td>
12 <td class=
"header-group page-location"><a href=
"../refmanual.html" class=
"navigation-link">Front Page
</a> /
<a href=
"./algorithms.html" class=
"navigation-link">Algorithms
</a> /
<a href=
"./querying-algorithms.html" class=
"navigation-link">Querying Algorithms
</a> /
<a href=
"./find-if.html" class=
"navigation-link">find_if
</a></td>
13 </tr></table><div class=
"header-separator"></div>
14 <div class=
"section" id=
"find-if">
15 <h1><a class=
"toc-backref" href=
"./querying-algorithms.html#id1476">find_if
</a></h1>
16 <div class=
"section" id=
"id543">
17 <h3><a class=
"subsection-title" href=
"#synopsis" name=
"synopsis">Synopsis
</a></h3>
18 <pre class=
"literal-block">
23 struct
<a href=
"./find-if.html" class=
"identifier">find_if
</a>
25 typedef
<em>unspecified
</em> type;
29 <div class=
"section" id=
"id544">
30 <h3><a class=
"subsection-title" href=
"#description" name=
"description">Description
</a></h3>
31 <p>Returns an iterator to the first element in
<tt class=
"literal"><span class=
"pre">Sequence
</span></tt> that satisfies
32 the predicate
<tt class=
"literal"><span class=
"pre">Pred
</span></tt>.
</p>
34 <div class=
"section" id=
"id545">
35 <h3><a class=
"subsection-title" href=
"#header" name=
"header">Header
</a></h3>
36 <pre class=
"literal-block">
37 #include
<<a href=
"../../../../boost/mpl/find_if.hpp" class=
"header">boost/mpl/find_if.hpp
</a>>
40 <div class=
"section" id=
"id546">
41 <h3><a class=
"subsection-title" href=
"#parameters" name=
"parameters">Parameters
</a></h3>
42 <table border=
"1" class=
"docutils table">
48 <thead valign=
"bottom">
49 <tr><th class=
"head">Parameter
</th>
50 <th class=
"head">Requirement
</th>
51 <th class=
"head">Description
</th>
55 <tr><td><tt class=
"literal"><span class=
"pre">Sequence
</span></tt></td>
56 <td><a class=
"reference internal" href=
"./forward-sequence.html">Forward Sequence
</a></td>
57 <td>A sequence to search in.
</td>
59 <tr><td><tt class=
"literal"><span class=
"pre">Pred
</span></tt></td>
60 <td>Unary
<a class=
"reference internal" href=
"./lambda-expression.html">Lambda Expression
</a></td>
61 <td>A search condition.
</td>
66 <div class=
"section" id=
"id547">
67 <h3><a class=
"subsection-title" href=
"#expression-semantics" name=
"expression-semantics">Expression semantics
</a></h3>
68 <p>For any
<a class=
"reference internal" href=
"./forward-sequence.html">Forward Sequence
</a> <tt class=
"literal"><span class=
"pre">s
</span></tt> and unary
<a class=
"reference internal" href=
"./lambda-expression.html">Lambda Expression
</a> <tt class=
"literal"><span class=
"pre">pred
</span></tt>:
</p>
69 <pre class=
"literal-block">
70 typedef
<a href=
"./find-if.html" class=
"identifier">find_if
</a><s,pred
>::type i;
72 <table class=
"docutils field-list" frame=
"void" rules=
"none">
73 <col class=
"field-name" />
74 <col class=
"field-body" />
76 <tr class=
"field"><th class=
"field-name">Return type:
</th><td class=
"field-body"><p class=
"first"><a class=
"reference internal" href=
"./forward-iterator.html">Forward Iterator
</a>.
</p>
79 <tr class=
"field"><th class=
"field-name">Semantics:
</th><td class=
"field-body"><p class=
"first"><tt class=
"literal"><span class=
"pre">i
</span></tt> is the first iterator in the range [
<tt class=
"literal"><span class=
"pre"><a href=
"./begin.html" class=
"identifier">begin
</a><s
>::type
</span></tt>,
<tt class=
"literal"><span class=
"pre"><a href=
"./end.html" class=
"identifier">end
</a><s
>::type
</span></tt>) such that
</p>
80 <pre class=
"literal-block">
81 <a href=
"./apply.html" class=
"identifier">apply
</a>< pred,
<a href=
"./deref.html" class=
"identifier">deref
</a><i
>::type
>::type::value == true
83 <p class=
"last">If no such iterator exists,
<tt class=
"literal"><span class=
"pre">i
</span></tt> is identical to
<tt class=
"literal"><span class=
"pre"><a href=
"./end.html" class=
"identifier">end
</a><s
>::type
</span></tt>.
</p>
89 <div class=
"section" id=
"id548">
90 <h3><a class=
"subsection-title" href=
"#complexity" name=
"complexity">Complexity
</a></h3>
91 <p>Linear. At most
<tt class=
"literal"><span class=
"pre"><a href=
"./size.html" class=
"identifier">size
</a><s
>::value
</span></tt> applications of
<tt class=
"literal"><span class=
"pre">pred
</span></tt>.
</p>
93 <div class=
"section" id=
"id549">
94 <h3><a class=
"subsection-title" href=
"#example" name=
"example">Example
</a></h3>
95 <pre class=
"literal-block">
96 typedef
<a href=
"./vector.html" class=
"identifier">vector
</a><char,int,unsigned,long,unsigned long
> types;
97 typedef
<a href=
"./find-if.html" class=
"identifier">find_if
</a><types, is_same
<<a href=
"./placeholders.html" class=
"identifier">_1
</a>,unsigned
> >::type iter;
99 <a href=
"./assert.html" class=
"identifier">BOOST_MPL_ASSERT
</a>(( is_same
< <a href=
"./deref.html" class=
"identifier">deref
</a><iter
>::type, unsigned
> ));
100 <a href=
"./assert-relation.html" class=
"identifier">BOOST_MPL_ASSERT_RELATION
</a>( iter::pos::value, ==,
2 );
103 <div class=
"section" id=
"id550">
104 <h3><a class=
"subsection-title" href=
"#see-also" name=
"see-also">See also
</a></h3>
105 <p><a class=
"reference internal" href=
"./querying-algorithms.html">Querying Algorithms
</a>,
<a class=
"reference internal" href=
"./find.html">find
</a>,
<a class=
"reference internal" href=
"./count-if.html">count_if
</a>,
<a class=
"reference internal" href=
"./lower-bound.html">lower_bound
</a></p>
106 <!-- Algorithms/Querying Algorithms//contains |30 -->
110 <div class=
"footer-separator"></div>
111 <table class=
"footer"><tr class=
"footer"><td class=
"header-group navigation-bar"><span class=
"navigation-group"><a href=
"./find.html" class=
"navigation-link">Prev
</a> <a href=
"./contains.html" class=
"navigation-link">Next
</a></span><span class=
"navigation-group-separator"> |
</span><span class=
"navigation-group"><a href=
"./find.html" class=
"navigation-link">Back
</a> <a href=
"./contains.html" class=
"navigation-link">Along
</a></span><span class=
"navigation-group-separator"> |
</span><span class=
"navigation-group"><a href=
"./querying-algorithms.html" class=
"navigation-link">Up
</a> <a href=
"../refmanual.html" class=
"navigation-link">Home
</a></span><span class=
"navigation-group-separator"> |
</span><span class=
"navigation-group"><a href=
"./refmanual_toc.html" class=
"navigation-link">Full TOC
</a></span></td>
112 <td><div class=
"copyright-footer"><div class=
"copyright">Copyright ©
2001-
2009 Aleksey Gurtovoy and David Abrahams
</div>
113 Distributed under the Boost Software License, Version
1.0. (See accompanying
114 file LICENSE_1_0.txt or copy at
<a class=
"reference external" href=
"http://www.boost.org/LICENSE_1_0.txt" target=
"_top">http://www.boost.org/LICENSE_1_0.txt
</a>)
</div></td></tr></table></body>