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not2 [C++ Reference]
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<li class="level1"><div class="li"><span class="li"><a href="#not2" class="toc">not2</a></span></div>
<ul class="toc">
<li class="clear">
<ul class="toc">
<li class="level3"><div class="li"><span class="li"><a href="#parameters" class="toc">Parameters</a></span></div></li>
<li class="level3"><div class="li"><span class="li"><a href="#predicate" class="toc">Predicate</a></span></div></li>
</ul>
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</ul>
</li>
<li class="level1"><div class="li"><span class="li"><a href="#return_value" class="toc">Return value</a></span></div></li>
<li class="level1"><div class="li"><span class="li"><a href="#example" class="toc">Example</a></span></div></li></ul>
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<h1><a name="not2" id="not2">not2</a></h1>
<div class="level1">
<pre class="c code c++" style="font-family:monospace;"><span class="kw2">function</span> template<span class="sy0"><</span>functional<span class="sy0">></span>template <span class="sy0"><</span>class Predicate<span class="sy0">></span>
binary_negate<span class="sy0"><</span>Predicate<span class="sy0">></span> not2 <span class="br0">(</span><span class="kw4">const</span> Predicate<span class="sy0">&</span> pred<span class="br0">)</span><span class="sy0">;</span></pre>
</div>
<h5><a name="return_negation_of_binary_function_object" id="return_negation_of_binary_function_object">Return negation of binary function object</a></h5>
<div class="level5">
<p>
This function constructs a function object that has the opposite behavior of pred (its argument, another function object).
</p>
<p>
Function objects are objects whose class defines member function operator(). This member function allows the object to be used with the same syntax as a regular function call, and therefore it can be used in templates instead of a pointer to a function.
</p>
<p>
The function object returned by not2 has its operator() defined such that it returns true when pred would return false, and false when pred would return true.
</p>
<p>
It is defined with the same behavior as:
</p>
<pre class="c code c++" style="font-family:monospace;"> template <span class="sy0"><</span>class Predicate<span class="sy0">></span>
binary_negate<span class="sy0"><</span>Predicate<span class="sy0">></span> not2 <span class="br0">(</span><span class="kw4">const</span> Predicate<span class="sy0">&</span> pred<span class="br0">)</span>
<span class="br0">{</span>
<span class="kw1">return</span> binary_negate<span class="sy0"><</span>Predicate<span class="sy0">></span><span class="br0">(</span>pred<span class="br0">)</span><span class="sy0">;</span>
<span class="br0">}</span></pre>
<p>
not2 is specifically designed to negate function objects (predicates) derived from binary_function (members first_argument_type and second_argument_type are required). For unary function objects, see not1.
</p>
</div>
<h3><a name="parameters" id="parameters">Parameters</a></h3>
<div class="level3">
</div>
<h3><a name="predicate" id="predicate">Predicate</a></h3>
<div class="level3">
<p>
Binary function object derived from binary_function.
</p>
</div>
<h1><a name="return_value" id="return_value">Return value</a></h1>
<div class="level1">
<p>
A binary function object with the opposite behavior of pred.
binary_negate is a type derived from binary_function.
</p>
</div>
<h1><a name="example" id="example">Example</a></h1>
<div class="level1">
<pre class="c code c++" style="font-family:monospace;"> <span class="co1">// not2 example</span>
<span class="co2">#include <iostream></span>
<span class="co2">#include <functional></span>
<span class="co2">#include <algorithm></span>
using namespace std<span class="sy0">;</span>
<span class="kw4">int</span> main <span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw4">int</span> foo<span class="br0">[</span><span class="br0">]</span> <span class="sy0">=</span> <span class="br0">{</span>10<span class="sy0">,</span>20<span class="sy0">,</span>30<span class="sy0">,</span>40<span class="sy0">,</span>50<span class="br0">}</span><span class="sy0">;</span>
<span class="kw4">int</span> bar<span class="br0">[</span><span class="br0">]</span> <span class="sy0">=</span> <span class="br0">{</span>0<span class="sy0">,</span>15<span class="sy0">,</span>30<span class="sy0">,</span>45<span class="sy0">,</span>60<span class="br0">}</span><span class="sy0">;</span>
pair<span class="sy0"><</span>int<span class="sy0">*,</span><span class="kw4">int</span><span class="sy0">*></span> firstmatch<span class="sy0">,</span>firstmismatch<span class="sy0">;</span>
firstmismatch<span class="sy0">=</span>mismatch <span class="br0">(</span>foo<span class="sy0">,</span> foo<span class="sy0">+</span>5<span class="sy0">,</span> bar<span class="sy0">,</span> equal_to<span class="sy0"><</span>int<span class="sy0">></span><span class="br0">(</span><span class="br0">)</span> <span class="br0">)</span><span class="sy0">;</span>
firstmatch<span class="sy0">=</span>mismatch <span class="br0">(</span>foo<span class="sy0">,</span> foo<span class="sy0">+</span>5<span class="sy0">,</span> bar<span class="sy0">,</span> not2<span class="br0">(</span>equal_to<span class="sy0"><</span>int<span class="sy0">></span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span> <span class="br0">)</span><span class="sy0">;</span>
<a href="http://www.opengroup.org/onlinepubs/009695399/functions/cout.html"><span class="kw3">cout</span></a> <span class="sy0"><<</span> <span class="st0">"First mismatch in bar is "</span> <span class="sy0"><<</span> <span class="sy0">*</span>firstmismatch.<span class="me1">second</span> <span class="sy0"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy0">;</span>
<a href="http://www.opengroup.org/onlinepubs/009695399/functions/cout.html"><span class="kw3">cout</span></a> <span class="sy0"><<</span> <span class="st0">"First match in bar is "</span> <span class="sy0"><<</span> <span class="sy0">*</span>firstmatch.<span class="me1">second</span> <span class="sy0"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy0">;</span>
<span class="kw1">return</span> <span class="nu0">0</span><span class="sy0">;</span>
<span class="br0">}</span></pre><pre class="c code c++" style="font-family:monospace;">First mismatch in bar is <span class="nu0">0</span>
First match in bar is <span class="nu0">30</span></pre>
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