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  26 <div class="titlepage"><div><div><h4 class="title">
  27 <a name="phoenix.modules.statement.switch__statement"></a><a class="link" href="switch__statement.html" title="switch_ Statement">switch_
  28         Statement</a>
  29 </h4></div></div></div>
  30 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">phoenix</span><span class="special">/</span><span class="identifier">statement</span><span class="special">/</span><span class="keyword">switch</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
  31 </pre>
  32 <p>
  33           The syntax is:
  34         </p>
  35 <pre class="programlisting"><span class="identifier">switch_</span><span class="special">(</span><span class="identifier">integral_expression</span><span class="special">)</span>
  36 <span class="special">[</span>
  37     <span class="identifier">case_</span><span class="special">&lt;</span><span class="identifier">integral_value</span><span class="special">&gt;(</span><span class="identifier">sequenced_statements</span><span class="special">),</span>
  38     <span class="special">...</span>
  39     <span class="identifier">default_</span><span class="special">&lt;</span><span class="identifier">integral_value</span><span class="special">&gt;(</span><span class="identifier">sequenced_statements</span><span class="special">)</span>
  40 <span class="special">]</span>
  41 </pre>
  42 <p>
  43           A comma separated list of cases, and an optional default can be provided.
  44           Note unlike a normal switch statement, cases do not fall through.
  45         </p>
  46 <p>
  47           Example: This code prints out <code class="computeroutput"><span class="string">"one"</span></code>,
  48           <code class="computeroutput"><span class="string">"two"</span></code> or <code class="computeroutput"><span class="string">"other value"</span></code> depending on the
  49           element's actual value:
  50         </p>
  51 <pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">for_each</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>
  52     <span class="identifier">switch_</span><span class="special">(</span><span class="identifier">arg1</span><span class="special">)</span>
  53     <span class="special">[</span>
  54         <span class="identifier">case_</span><span class="special">&lt;</span><span class="number">1</span><span class="special">&gt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">val</span><span class="special">(</span><span class="string">"one"</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="char">'\n'</span><span class="special">),</span>
  55         <span class="identifier">case_</span><span class="special">&lt;</span><span class="number">2</span><span class="special">&gt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">val</span><span class="special">(</span><span class="string">"two"</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="char">'\n'</span><span class="special">),</span>
  56         <span class="identifier">default_</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">val</span><span class="special">(</span><span class="string">"other value"</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="char">'\n'</span><span class="special">)</span>
  57     <span class="special">]</span>
  58 <span class="special">);</span>
  59 </pre>
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  65         Distributed under the Boost Software License, Version 1.0. (See accompanying
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