&quot;Hello from a thread!&quot;</span>
    });

    <span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{}&quot;</span>, <span class='ident'>handle</span>.<span class='ident'>join</span>().<span class='ident'>unwrap</span>());
}</pre>

<!-- Many languages have the ability to execute threads, but it's wildly unsafe. -->

<!-- There are entire books about how to prevent errors that occur from shared -->

<!-- mutable state. Rust helps out with its type system here as wel