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<div class="titlepage"><div><div><h3 class="title">
<a name="the_boost_algorithm_library.CXX11.any_of"></a><a class="link" href="any_of.html" title="any_of">any_of</a>
</h3></div></div></div>
<p>
        The header file 'boost/algorithm/cxx11/any_of.hpp' contains four variants
        of a single algorithm, <code class="computeroutput"><span class="identifier">any_of</span></code>.
        The algorithm tests the elements of a sequence and returns true if any of
        the elements has a particular property.
      </p>
<p>
        The routine <code class="computeroutput"><span class="identifier">any_of</span></code> takes
        a sequence and a predicate. It will return true if the predicate returns
        true for any element in the sequence.
      </p>
<p>
        The routine <code class="computeroutput"><span class="identifier">any_of_equal</span></code>
        takes a sequence and a value. It will return true if any element in the sequence
        compares equal to the passed in value.
      </p>
<p>
        Both routines come in two forms; the first one takes two iterators to define
        the range. The second form takes a single range parameter, and uses Boost.Range
        to traverse it.
      </p>
<h5>
<a name="the_boost_algorithm_library.CXX11.any_of.h0"></a>
        <span class="phrase"><a name="the_boost_algorithm_library.CXX11.any_of.interface"></a></span><a class="link" href="any_of.html#the_boost_algorithm_library.CXX11.any_of.interface">interface</a>
      </h5>
<p>
        The function <code class="computeroutput"><span class="identifier">any_of</span></code> returns
        true if the predicate returns true any item in the sequence. There are two
        versions; one takes two iterators, and the other takes a range.
      </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">algorithm</span> <span class="special">{</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">InputIterator</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Predicate</span><span class="special">&gt;</span>
	<span class="keyword">bool</span> <span class="identifier">any_of</span> <span class="special">(</span> <span class="identifier">InputIterator</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">InputIterator</span> <span class="identifier">last</span><span class="special">,</span> <span class="identifier">Predicate</span> <span class="identifier">p</span> <span class="special">);</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Range</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Predicate</span><span class="special">&gt;</span>
	<span class="keyword">bool</span> <span class="identifier">any_of</span> <span class="special">(</span> <span class="keyword">const</span> <span class="identifier">Range</span> <span class="special">&amp;</span><span class="identifier">r</span><span class="special">,</span> <span class="identifier">Predicate</span> <span class="identifier">p</span> <span class="special">);</span>
<span class="special">}}</span>
</pre>
<p>
      </p>
<p>
        The function <code class="computeroutput"><span class="identifier">any_of_equal</span></code>
        is similar to <code class="computeroutput"><span class="identifier">any_of</span></code>, but
        instead of taking a predicate to test the elements of the sequence, it takes
        a value to compare against.
      </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">algorithm</span> <span class="special">{</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">InputIterator</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">V</span><span class="special">&gt;</span>
	<span class="keyword">bool</span> <span class="identifier">any_of_equal</span> <span class="special">(</span> <span class="identifier">InputIterator</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">InputIterator</span> <span class="identifier">last</span><span class="special">,</span> <span class="identifier">V</span> <span class="keyword">const</span> <span class="special">&amp;</span><span class="identifier">val</span> <span class="special">);</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Range</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">V</span><span class="special">&gt;</span>
	<span class="keyword">bool</span> <span class="identifier">any_of_equal</span> <span class="special">(</span> <span class="keyword">const</span> <span class="identifier">Range</span> <span class="special">&amp;</span><span class="identifier">r</span><span class="special">,</span> <span class="identifier">V</span> <span class="keyword">const</span> <span class="special">&amp;</span><span class="identifier">val</span> <span class="special">);</span>
<span class="special">}}</span>
</pre>
<p>
      </p>
<h5>
<a name="the_boost_algorithm_library.CXX11.any_of.h1"></a>
        <span class="phrase"><a name="the_boost_algorithm_library.CXX11.any_of.examples"></a></span><a class="link" href="any_of.html#the_boost_algorithm_library.CXX11.any_of.examples">Examples</a>
      </h5>
<p>
        Given the container <code class="computeroutput"><span class="identifier">c</span></code> containing
        <code class="computeroutput"><span class="special">{</span> <span class="number">0</span><span class="special">,</span> <span class="number">1</span><span class="special">,</span>
        <span class="number">2</span><span class="special">,</span> <span class="number">3</span><span class="special">,</span> <span class="number">14</span><span class="special">,</span> <span class="number">15</span> <span class="special">}</span></code>,
        then
</p>
<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">isOdd</span> <span class="special">(</span> <span class="keyword">int</span> <span class="identifier">i</span> <span class="special">)</span> <span class="special">{</span> <span class="keyword">return</span> <span class="identifier">i</span> <span class="special">%</span> <span class="number">2</span> <span class="special">==</span> <span class="number">1</span><span class="special">;</span> <span class="special">}</span>
<span class="keyword">bool</span> <span class="identifier">lessThan10</span> <span class="special">(</span> <span class="keyword">int</span> <span class="identifier">i</span> <span class="special">)</span> <span class="special">{</span> <span class="keyword">return</span> <span class="identifier">i</span> <span class="special">&lt;</span> <span class="number">10</span><span class="special">;</span> <span class="special">}</span>

<span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">algorithm</span><span class="special">;</span>
<span class="identifier">any_of</span> <span class="special">(</span> <span class="identifier">c</span><span class="special">,</span> <span class="identifier">isOdd</span> <span class="special">)</span> <span class="special">--&gt;</span> <span class="keyword">true</span>
<span class="identifier">any_of</span> <span class="special">(</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">begin</span> <span class="special">(),</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">end</span> <span class="special">(),</span> <span class="identifier">lessThan10</span> <span class="special">)</span> <span class="special">--&gt;</span> <span class="keyword">true</span>
<span class="identifier">any_of</span> <span class="special">(</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">begin</span> <span class="special">()</span> <span class="special">+</span> <span class="number">4</span><span class="special">,</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">end</span> <span class="special">(),</span> <span class="identifier">lessThan10</span> <span class="special">)</span> <span class="special">--&gt;</span> <span class="keyword">false</span>
<span class="identifier">any_of</span> <span class="special">(</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">end</span> <span class="special">(),</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">end</span> <span class="special">(),</span> <span class="identifier">isOdd</span> <span class="special">)</span> <span class="special">--&gt;</span> <span class="keyword">false</span>  <span class="comment">// empty range</span>
<span class="identifier">any_of_equal</span> <span class="special">(</span> <span class="identifier">c</span><span class="special">,</span> <span class="number">3</span> <span class="special">)</span> <span class="special">--&gt;</span> <span class="keyword">true</span>
<span class="identifier">any_of_equal</span> <span class="special">(</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">begin</span> <span class="special">(),</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">begin</span> <span class="special">()</span> <span class="special">+</span> <span class="number">3</span><span class="special">,</span> <span class="number">3</span> <span class="special">)</span> <span class="special">--&gt;</span> <span class="keyword">false</span>
<span class="identifier">any_of_equal</span> <span class="special">(</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">begin</span> <span class="special">(),</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">begin</span> <span class="special">(),</span> <span class="number">99</span> <span class="special">)</span> <span class="special">--&gt;</span> <span class="keyword">false</span>  <span class="comment">// empty range</span>
</pre>
<p>
      </p>
<h5>
<a name="the_boost_algorithm_library.CXX11.any_of.h2"></a>
        <span class="phrase"><a name="the_boost_algorithm_library.CXX11.any_of.iterator_requirements"></a></span><a class="link" href="any_of.html#the_boost_algorithm_library.CXX11.any_of.iterator_requirements">Iterator
        Requirements</a>
      </h5>
<p>
        <code class="computeroutput"><span class="identifier">any_of</span></code> and <code class="computeroutput"><span class="identifier">any_of_equal</span></code> work on all iterators except
        output iterators.
      </p>
<h5>
<a name="the_boost_algorithm_library.CXX11.any_of.h3"></a>
        <span class="phrase"><a name="the_boost_algorithm_library.CXX11.any_of.complexity"></a></span><a class="link" href="any_of.html#the_boost_algorithm_library.CXX11.any_of.complexity">Complexity</a>
      </h5>
<p>
        All of the variants of <code class="computeroutput"><span class="identifier">any_of</span></code>
        and <code class="computeroutput"><span class="identifier">any_of_equal</span></code> run in
        <span class="emphasis"><em>O(N)</em></span> (linear) time; that is, they compare against each
        element in the list once. If any of the comparisons succeed, the algorithm
        will terminate immediately, without examining the remaining members of the
        sequence.
      </p>
<h5>
<a name="the_boost_algorithm_library.CXX11.any_of.h4"></a>
        <span class="phrase"><a name="the_boost_algorithm_library.CXX11.any_of.exception_safety"></a></span><a class="link" href="any_of.html#the_boost_algorithm_library.CXX11.any_of.exception_safety">Exception
        Safety</a>
      </h5>
<p>
        All of the variants of <code class="computeroutput"><span class="identifier">any_of</span></code>
        and <code class="computeroutput"><span class="identifier">any_of_equal</span></code> take their
        parameters by value or const reference, and do not depend upon any global
        state. Therefore, all the routines in this file provide the strong exception
        guarantee.
      </p>
<h5>
<a name="the_boost_algorithm_library.CXX11.any_of.h5"></a>
        <span class="phrase"><a name="the_boost_algorithm_library.CXX11.any_of.notes"></a></span><a class="link" href="any_of.html#the_boost_algorithm_library.CXX11.any_of.notes">Notes</a>
      </h5>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
            The routine <code class="computeroutput"><span class="identifier">any_of</span></code> is
            also available as part of the C++11 standard.
          </li>
<li class="listitem">
            <code class="computeroutput"><span class="identifier">any_of</span></code> and <code class="computeroutput"><span class="identifier">any_of_equal</span></code> both return false for
            empty ranges, no matter what is passed to test against.
          </li>
<li class="listitem">
            The second parameter to <code class="computeroutput"><span class="identifier">any_of_value</span></code>
            is a template parameter, rather than deduced from the first parameter
            (<code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">iterator_traits</span><span class="special">&lt;</span><span class="identifier">InputIterator</span><span class="special">&gt;::</span><span class="identifier">value_type</span></code>) because that allows more
            flexibility for callers, and takes advantage of built-in comparisons
            for the type that is pointed to by the iterator. The function is defined
            to return true if, for any element in the sequence, the expression <code class="computeroutput"><span class="special">*</span><span class="identifier">iter</span> <span class="special">==</span> <span class="identifier">val</span></code>
            evaluates to true (where <code class="computeroutput"><span class="identifier">iter</span></code>
            is an iterator to each element in the sequence)
          </li>
</ul></div>
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