�こで導入しているクロージャ内に移すことができます。</p>
<!--
<span class="filename">Filename: src/main.rs</span>
-->
<p><span class="filename">ファイル名: src/main.rs</span></p>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span><span class="boring">use std::thread;
</span><span class="boring">use std::time::Duration;
</span><span class="boring">
</span>let expensive_closure = |num| {
  