<a name="boost.contract.call_if"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle">Function template call_if</span></h2>
-<p>boost::contract::call_if — Select compilation and execution of functor template calls using a nullary boolean meta-function. </p>
+<p>boost::contract::call_if — Select compilation and execution of functor template calls using a nullary boolean meta-function (not needed on C++17 compilers, use <code class="computeroutput">if constexpr</code> instead). </p>
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<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../reference.html#header.boost.contract.call_if_hpp" title="Header <boost/contract/call_if.hpp>">boost/contract/call_if.hpp</a>>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Pred<span class="special">,</span> <span class="keyword">typename</span> Then<span class="special">></span>
<a class="link" href="call_if_statement.html" title="Struct template call_if_statement">call_if_statement</a><span class="special"><</span> <span class="identifier">Pred</span><span class="special">::</span><span class="identifier">value</span><span class="special">,</span> <span class="identifier">Then</span> <span class="special">></span> <span class="identifier">call_if</span><span class="special">(</span><span class="identifier">Then</span> f<span class="special">)</span><span class="special">;</span></pre></div>
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-<a name="idm45751731093920"></a><h2>Description</h2>
+<a name="idm45707997647376"></a><h2>Description</h2>
<p>This is equivalent to <code class="computeroutput">boost::contract::call_if_c<Pred::value>(f)</code>. Create a call-if object with the specified then-branch functor template:</p>
<pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">contract</span><span class="special">::</span><span class="identifier">call_if</span><span class="special"><</span><span class="identifier">Pred1</span><span class="special">></span><span class="special">(</span>
<span class="identifier">then_functor_template1</span>
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<td><p><span class="term">Returns:</span></p></td>
-<td><p>A call-if statement so else and else-if statements can be specified if needed. Eventually, this will be the return value of the functor template call being compiled and executed (which can also be <code class="computeroutput">void</code>). </p></td>
+<td><p>A call-if statement so else and else-if statements can be specified if needed. Eventually, this will be the return value of the one functor template call being compiled and executed (which could also be <code class="computeroutput">void</code>). </p></td>
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-<td align="right"><div class="copyright-footer">Copyright © 2008-2018 Lorenzo Caminiti<p>
+<td align="right"><div class="copyright-footer">Copyright © 2008-2019 Lorenzo Caminiti<p>
Distributed under the Boost Software License, Version 1.0 (see accompanying
file LICENSE_1_0.txt or a copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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