<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div><blockquote type="cite" class=""><div class="">On Apr 6, 2017, at 9:51 AM, Nate Cook <<a href="mailto:nate@natecook.com" class="">nate@natecook.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">Thanks for all your feedback, Brent! One note on this item in particular—if you specify a default argument for a throws/rethrows closure, you have to use "try" at the call site even if the default closure argument doesn't throw. Modules currently don't promise that default closure arguments don't throw, and a default argument could change from non-throwing to throwing in a later version of a library.</div><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class=""></div><div style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">There's a bug tracking the issue here: <a href="https://bugs.swift.org/browse/SR-2979" class="">https://bugs.swift.org/browse/SR-2979</a></div></div></blockquote></div><div class=""><br class=""></div><div class="">Ugh. If that's the case, I'd probably provide a merge-handler-argument-less version instead of using a default argument. But I would have the first argument of both be unlabeled.</div><div class=""><br class=""></div><div class="">Actually, if we're going to do that, maybe the non-merge-handling version should be failable. That's the one semantic a `resolveConflict` method can't provide, and of course trapping on error is still just one force-unwrap away if that's what you want.</div><div class=""><br class=""></div><div class="">So that would give us:</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>init?<S: Sequence>(_ keysAndValues: S)</div><div class=""><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class=""><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>where S.Iterator.Element == (key: Key, value: Value)</div></div></div></div></div><div class=""><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class=""><div class=""><br class=""></div></div></div></div></div><div class=""><span class="Apple-tab-span" style="white-space:pre"> </span>init<S: Sequence>(_ keysAndValues: S, correctingConflictsBy resolveConflict: (Value, Value) throws -> Value) rethrows<br class=""><span class="Apple-tab-span" style="white-space:pre"> </span>where S.Iterator.Element == (key: Key, value: Value)<br class=""><br class=""></div><div class="">I think that pretty much covers everything you could possibly want to do about a conflict.</div><div class=""><br class=""></div><div class="">(I'd do a similar thing to `merged`, and perhaps have `merge` return a Bool, if you don't give them `resolveConflict` functions.)</div><div class=""><br class=""></div><div class="">
<span class="Apple-style-span" style="border-collapse: separate; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; line-height: normal; border-spacing: 0px;"><div class=""><div style="font-size: 12px; " class="">-- </div><div style="font-size: 12px; " class="">Brent Royal-Gordon</div><div style="font-size: 12px; " class="">Architechies</div></div></span>
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