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.error { color:#AA0000; }</style></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class="bloop_markdown"><p>How about?</p>
<pre><code>public func ?? <T>(optional: T?, noreturnOrError: @autoclosure () throws -> Never) rethrows -> T {
switch optional {
case .some(let value):
return value
case .none:
try noreturnOrError()
}
}
</code></pre>
<p></p></div><div class="bloop_original_html"><style>body{font-family:Helvetica,Arial;font-size:13px}</style><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div> <br> <div id="bloop_sign_1498593590478208000" class="bloop_sign"><div style="font-family:helvetica,arial;font-size:13px">-- <br>Adrian Zubarev<br>Sent with Airmail</div></div> <br><p class="airmail_on">Am 27. Juni 2017 um 21:54:57, Max Moiseev via swift-evolution (<a href="mailto:swift-evolution@swift.org">swift-evolution@swift.org</a>) schrieb:</p> <blockquote type="cite" class="clean_bq"><span><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div></div><div>
<title></title>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">On Jun 27, 2017, at 10:38 AM, Xiaodi Wu via
swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:</div>
<br class="Apple-interchange-newline">
<div class="">As you write, this operator becomes sugar for “??
fatalError()” once Never becomes a true bottom type.<br class="">
<br class="">
In the meantime, can’t the same thing be accomplished by
overloading fatalError so it’s a generic function that returns a
discardable result of type T, which in turn calls the
Never-returning overload?<br class=""></div>
</blockquote>
<div><br class=""></div>
<div>I like this idea more than adding an extra operator, but
overloading fatalError won’t work now because of <a href="https://github.com/apple/swift/blob/master/stdlib/public/core/Optional.swift#L668" class="">https://github.com/apple/swift/blob/master/stdlib/public/core/Optional.swift#L668</a></div>
<div><br class=""></div>
<div><br class=""></div>
<div><br class=""></div>
<br class="">
<blockquote type="cite" class="">
<div class="">
<div class="gmail_quote">
<div dir="ltr" class="">On Tue, Jun 27, 2017 at 12:25 Erica Sadun
via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:<br class=""></div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div style="word-wrap:break-word" class="">
<div class="">Using an operator to provide feedback on the context
of a failed unwrap has become a commonly implemented approach in
the Swift developer Community. What are your thoughts about
adopting this widely-used operator into the standard library?</div>
<div class=""><br class=""></div>
<div class=""><font face="Menlo" class="">guard !lastItem.isEmpty
else { return }</font></div>
<div class=""><font face="Menlo" class="">let lastItem = array.last
!! "Array must be non-empty"</font></div>
<div class=""><br class=""></div>
<div class="">Details here: <a href="https://gist.github.com/erica/423e4b1c63b95c4c90338cdff4939a9b" target="_blank" class="">https://gist.github.com/erica/423e4b1c63b95c4c90338cdff4939a9b</a></div>
<div class=""><br class=""></div>
<div class="">Thank you for your thoughtful feedback, -- E</div>
<div class=""><br class=""></div>
</div>
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<a href="https://lists.swift.org/mailman/listinfo/swift-evolution" rel="noreferrer" target="_blank" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class="">
</blockquote>
</div>
_______________________________________________<br class="">
swift-evolution mailing list<br class="">
<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><br class="">
https://lists.swift.org/mailman/listinfo/swift-evolution<br class=""></div>
</blockquote>
</div>
<br class="">
_______________________________________________<br>swift-evolution mailing list<br>swift-evolution@swift.org<br>https://lists.swift.org/mailman/listinfo/swift-evolution<br></div></div></span></blockquote></div><div class="bloop_markdown"><p></p></div></body></html>