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      <div class="chatlog__message-aside"><img class="chatlog__avatar" src="https://cdn.discordapp.com/avatars/293624673265123328/accd07acc220a18568ba46a6e9ede18a.png?size=512" alt="Avatar" loading="lazy"></div>
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        <div class="chatlog__header"><span class="chatlog__author" style="color:rgb(17,128,106)" title="koher" data-user-id="293624673265123328">koher</span> <a href="/channels/306995750418513920?category=main&amp;channel=swift-2&amp;message_id=554704770422800384"><span class="chatlog__timestamp" title="Monday, March 11, 2019 4:38 PM"></span></a><a href="#chatlog__message-container-554704770422800384">3/11/2019 4:38 PM</a></div>
        <div class="chatlog__content chatlog__markdown"><span class="chatlog__markdown-preserve"><code class="chatlog__markdown-pre chatlog__markdown-pre--inline">typealias</code> で opaque result type はまだ許されてないようです。 <code class="chatlog__markdown-pre chatlog__markdown-pre--multiline language-swift">protocol Foo {} extension Int: Foo {} protocol P { associatedtype F: Foo func foo() -&gt; F } struct S: P { typealias F = __opaque Foo func foo() -&gt; F { return 42 } } let s = S() var a = s.foo() let b = s.foo() a = b</code>
            <code class="chatlog__markdown-pre chatlog__markdown-pre--multiline nohighlight">/path/to/opaque-result-0.swift:9:19: error: 'opaque' types are only implemented for the declared type of properties and subscripts and the return type of functions typealias F = __opaque Foo ^</code></span></div>
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