title: Why the `cycle()` method exists if `ChunksMut` is never `Clone?`
body: <p>The <a href="https://doc.rust-lang.org/std/slice/struct.ChunksMut.html" rel="nofollow noreferrer">https://doc.rust-lang.org/std/slice/struct.ChunksMut.html</a> has the cycle method: <a href="https://doc.rust-lang.org/std/iter/struct.Cycle.html#method.cycle" rel="nofollow noreferrer">https://doc.rust-lang.org/std/iter/struct.Cycle.html#method.cycle</a> that works only when <code>Self: Clone</code></p>
  <p>However, <code>ChunksMut</code> does not implement <code>Clone</code>, therefore I cannot do this:</p>
  <pre><code>fn main() {
      let a = &amp;[1,2,3,4,5,6];
      let mut chunks = a.chunks_mut(2);
      let cycle = chunks.cycle();
      for c in cycle {
          
      }
  }
  </code></pre>
  <p>Why the <code>cycle()</code> method exists if <code>ChunksMut</code> is never <code>Clone?</code></p>