an> <span class='ident'>main</span>() {
    <span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>data</span> <span class='op'>=</span> <span class='ident'>Arc</span>::<span class='ident'>new</span>(<span class='macro'>vec</span><span class='macro'>!</span>[<span class='number'>1</span>, <span class='number'>2</span>, <span class='number'>3</span>]);

    <span class='kw'>for</span> <span class='ident'>i</span> <span class='kw'>in</span> <span class='number'>0</span>..<span class='nu