ession that is equivalent to the `if let` and `else`. Recall the
`Coin` enum definition in Listing 6-4, where the `Quarter` variant also held a
`UsState` value. If we wanted to count all non-quarter coins we see while also
announcing the state of the quarters, we could do that with a `match`
expression like this:
-->
<p><code>if let</code>では、<code>else</code>を含むこともできます。<code>else</code>に入るコードブロックは、
<code>if let</code>と<code>else</code>に等価な<code>m