an> <span class='ident'>x</span> <span class='op'>=</span> <span class='kw-2'>&amp;</span><span class='ident'>data</span>[<span class='number'>0</span>];
<span class='ident'>data</span>.<span class='ident'>push</span>(<span class='number'>4</span>);
<span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{}&quot;</span>, <span class='ident'>x</span>);</pre>

<span class='rusttest'>fn main() {
    &#39;a: {
    let mut data: Vec&lt;i32&gt; = vec![1, 2, 3];
    &#39;b: {
    