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26<div class="titlepage"><div><div><h3 class="title">
27<a name="boost_typetraits.examples.to_double"></a><a class="link" href="to_double.html" title="Convert Numeric Types and Enums to double">Convert Numeric
28      Types and Enums to double</a>
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30<p>
31        Demonstrates a conversion of <a href="../../../../../../libs/numeric/conversion/doc/html/boost_numericconversion/definitions.html#boost_numericconversion.definitions.numeric_types" target="_top">Numeric
32        Types</a> and enum types to double:
33      </p>
34<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
35<span class="keyword">inline</span> <span class="keyword">double</span> <span class="identifier">to_double</span><span class="special">(</span><span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">value</span><span class="special">)</span>
36<span class="special">{</span>
37    <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">promote</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">promoted</span><span class="special">;</span>
38    <span class="keyword">return</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">converter</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">,</span><span class="identifier">promoted</span><span class="special">&gt;::</span><span class="identifier">convert</span><span class="special">(</span><span class="identifier">value</span><span class="special">);</span>
39<span class="special">}</span>
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