d_two_to_x</span>);
}

<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">x</span>, <span class="number">5</span>);</pre>
<p>Taking a <a href="trait.FnOnce.html"><code>FnOnce</code></a> as a parameter:</p>

<pre class="rust rust-example-rendered">
<span class="kw">fn</span> <span class="ident">consume_with_relish</span><span class="op">&lt;</span><span class="ident">F</span><span class="op">&gt;</span>(<span class="ident">func</span>: <span class="ident">F</span>)
    <span