ljs-type">Just</span> age -&gt;
      age &gt;= <span class="hljs-number">21</span>
</code></pre>
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Notice that the `Maybe` type forces us to pattern match on the user's age. It is actually impossible to write code where you forget that users may not have an age. Elm makes sure of it! Now we can advertise alcohol confident that we are not influencing minors directly! Only their older peers.
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<p><code>Maybe</code>&#x578B;&#x306F;&#x30E6;&#x30FC;&#x30B6;&#x306E;&#x5E74;&#x9F62;&#x3092;&#x4F7F;&#x3046;&#