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<h1 class='fqn'><span class='in-band'>Function <a href='../index.html'>core</a>::<wbr><a href='index.html'>iter</a>::<wbr><a class="fn" href=''>repeat</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'>
                   <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
                       [<span class='inner'>&#x2212;</span>]
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               </span><a class='srclink' href='../../src/core/iter/sources.rs.html#95-97' title='goto source code'>[src]</a></span></h1>
<pre class='rust fn'>pub fn repeat&lt;T:&nbsp;<a class="trait" href="../../core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>&gt;(elt: T) -&gt; <a class="struct" href="../../core/iter/struct.Repeat.html" title="struct core::iter::Repeat">Repeat</a>&lt;T&gt;</pre><div class='docblock'><p>Creates a new iterator that endlessly repeats a single element.</p>

<p>The <code>repeat()</code> function repeats a single value over and over and over and
over and over and 🔁.</p>

<p>Infinite iterators like <code>repeat()</code> are often used with adapters like
<a href="trait.Iterator.html#method.take"><code>take</code></a>, in order to make them finite.</p>

<h1 id='examples' class='section-header'><a href='#examples'>Examples</a></h1>
<p>Basic usage:</p>

<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">iter</span>;

<span class="comment">// the number four 4ever:</span>
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">fours</span> <span class="op">=</span> <span class="ident">iter</span>::<span class="ident">repeat</span>(<span class="number">4</span>);

<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">fours</span>.<span class="ident">next</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">fours</span>.<span class="ident">next</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">fours</span>.<span class="ident">next</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">fours</span>.<span class="ident">next</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">fours</span>.<span class="ident">next</span>());

<span class="comment">// yup, still four</span>
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">fours</span>.<span class="ident">next</span>());<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=fn%20main()%20%7B%0Ause%20std%3A%3Aiter%3B%0A%0A%2F%2F%20the%20number%20four%204ever%3A%0Alet%20mut%20fours%20%3D%20iter%3A%3Arepeat(4)%3B%0A%0Aassert_eq!(Some(4)%2C%20fours.next())%3B%0Aassert_eq!(Some(4)%2C%20fours.next())%3B%0Aassert_eq!(Some(4)%2C%20fours.next())%3B%0Aassert_eq!(Some(4)%2C%20fours.next())%3B%0Aassert_eq!(Some(4)%2C%20fours.next())%3B%0A%0A%2F%2F%20yup%2C%20still%20four%0Aassert_eq!(Some(4)%2C%20fours.next())%3B%0A%7D">Run</a></pre>

<p>Going finite with <a href="trait.Iterator.html#method.take"><code>take</code></a>:</p>

<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">iter</span>;

<span class="comment">// that last example was too many fours. Let&#39;s only have four fours.</span>
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">four_fours</span> <span class="op">=</span> <span class="ident">iter</span>::<span class="ident">repeat</span>(<span class="number">4</span>).<span class="ident">take</span>(<span class="number">4</span>);

<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">four_fours</span>.<span class="ident">next</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">four_fours</span>.<span class="ident">next</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">four_fours</span>.<span class="ident">next</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>), <span class="ident">four_fours</span>.<span class="ident">next</span>());

<span class="comment">// ... and now we&#39;re done</span>
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">None</span>, <span class="ident">four_fours</span>.<span class="ident">next</span>());<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=fn%20main()%20%7B%0Ause%20std%3A%3Aiter%3B%0A%0A%2F%2F%20that%20last%20example%20was%20too%20many%20fours.%20Let's%20only%20have%20four%20fours.%0Alet%20mut%20four_fours%20%3D%20iter%3A%3Arepeat(4).take(4)%3B%0A%0Aassert_eq!(Some(4)%2C%20four_fours.next())%3B%0Aassert_eq!(Some(4)%2C%20four_fours.next())%3B%0Aassert_eq!(Some(4)%2C%20four_fours.next())%3B%0Aassert_eq!(Some(4)%2C%20four_fours.next())%3B%0A%0A%2F%2F%20...%20and%20now%20we're%20done%0Aassert_eq!(None%2C%20four_fours.next())%3B%0A%7D">Run</a></pre>
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