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<h1 class='fqn'><span class='in-band'>Module <a href='../index.html'>std</a>::<wbr><a class="mod" href=''>clone</a></span><span class='out-of-band'><span class='since' title='Stable since Rust version 1.0.0'>1.0.0</span><span id='render-detail'>
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                       [<span class='inner'>&#x2212;</span>]
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               </span><a class='srclink' href='../../src/core/clone.rs.html#11-170' title='goto source code'>[src]</a></span></h1>
<div class='docblock'><p>The <code>Clone</code> trait for types that cannot be &#39;implicitly copied&#39;.</p>

<p>In Rust, some simple types are &quot;implicitly copyable&quot; and when you
assign them or pass them as arguments, the receiver will get a copy,
leaving the original value in place. These types do not require
allocation to copy and do not have finalizers (i.e. they do not
contain owned boxes or implement <a href="../../std/ops/trait.Drop.html"><code>Drop</code></a>), so the compiler considers
them cheap and safe to copy. For other types copies must be made
explicitly, by convention implementing the <a href="trait.Clone.html"><code>Clone</code></a> trait and calling
the <a href="trait.Clone.html#tymethod.clone"><code>clone</code></a> method.</p>

<p>Basic usage example:</p>

<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">new</span>(); <span class="comment">// String type implements Clone</span>
<span class="kw">let</span> <span class="ident">copy</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">clone</span>(); <span class="comment">// so we can clone it</span><a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=fn%20main()%20%7B%0Alet%20s%20%3D%20String%3A%3Anew()%3B%20%2F%2F%20String%20type%20implements%20Clone%0Alet%20copy%20%3D%20s.clone()%3B%20%2F%2F%20so%20we%20can%20clone%20it%0A%7D">Run</a></pre>

<p>To easily implement the Clone trait, you can also use
<code>#[derive(Clone)]</code>. Example:</p>

<pre class="rust rust-example-rendered">
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Clone</span>)]</span> <span class="comment">// we add the Clone trait to Morpheus struct</span>
<span class="kw">struct</span> <span class="ident">Morpheus</span> {
   <span class="ident">blue_pill</span>: <span class="ident">f32</span>,
   <span class="ident">red_pill</span>: <span class="ident">i64</span>,
}

<span class="kw">fn</span> <span class="ident">main</span>() {
   <span class="kw">let</span> <span class="ident">f</span> <span class="op">=</span> <span class="ident">Morpheus</span> { <span class="ident">blue_pill</span>: <span class="number">0.0</span>, <span class="ident">red_pill</span>: <span class="number">0</span> };
   <span class="kw">let</span> <span class="ident">copy</span> <span class="op">=</span> <span class="ident">f</span>.<span class="ident">clone</span>(); <span class="comment">// and now we can clone it!</span>
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23%5Bderive(Clone)%5D%20%2F%2F%20we%20add%20the%20Clone%20trait%20to%20Morpheus%20struct%0Astruct%20Morpheus%20%7B%0A%20%20%20blue_pill%3A%20f32%2C%0A%20%20%20red_pill%3A%20i64%2C%0A%7D%0A%0Afn%20main()%20%7B%0A%20%20%20let%20f%20%3D%20Morpheus%20%7B%20blue_pill%3A%200.0%2C%20red_pill%3A%200%20%7D%3B%0A%20%20%20let%20copy%20%3D%20f.clone()%3B%20%2F%2F%20and%20now%20we%20can%20clone%20it!%0A%7D%0A">Run</a></pre>
</div><h2 id='traits' class='section-header'><a href="#traits">Traits</a></h2>
<table>
                       <tr class=' module-item'>
                           <td><a class="trait" href="trait.Clone.html"
                                  title='trait std::clone::Clone'>Clone</a></td>
                           <td class='docblock-short'>
                                <p>A common trait for the ability to explicitly duplicate an object.</p>
                           </td>
                       </tr></table></section>
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