href="#cacher実装の限界"><code>Cacher</code>実装の限界</a></h3>
<!--
Caching values is a generally useful behavior that we might want to use in
other parts of our code with different closures. However, there are two
problems with the current implementation of `Cacher` that would make reusing it
in different contexts difficult.
-->
<p>値をキャッシュすることは、コードの他の部分でも異なるクロージャで行いたくなる可能性のある一般的に有用な振る舞い�