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<title>Improving std::min with common_type</title>
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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_typetraits.examples.improved_min"></a><a class="link" href="improved_min.html" title="Improving std::min with common_type">Improving std::min
with common_type</a>
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<p>
An improved <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">min</span></code> function could be written like this:
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U</span><span class="special">></span>
<span class="keyword">typename</span> <a class="link" href="../reference/common_type.html" title="common_type">common_type</a><span class="special"><</span><span class="identifier">T</span><span class="special">,</span> <span class="identifier">U</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">min</span><span class="special">(</span><span class="identifier">T</span> <span class="identifier">t</span><span class="special">,</span> <span class="identifier">T</span> <span class="identifier">u</span><span class="special">)</span>
<span class="special">{</span>
<span class="keyword">return</span> <span class="identifier">t</span> <span class="special"><</span> <span class="identifier">u</span> <span class="special">?</span> <span class="identifier">t</span> <span class="special">:</span> <span class="identifier">u</span><span class="special">;</span>
<span class="special">}</span>
</pre>
<p>
And now expressions such as:
</p>
<pre class="programlisting"><span class="identifier">min</span><span class="special">(</span><span class="number">1</span><span class="special">,</span> <span class="number">2.0</span><span class="special">)</span>
</pre>
<p>
will actually compile and return the correct type!
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