<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 class="">Right, it’s a recursion, because this </div><div class=""><div style="margin: 0px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""><br class=""></span></div><div style="margin: 0px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">(self </span><span style="font-variant-ligatures: no-common-ligatures;" class="">as</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures;" class="">FooPro</span><span style="font-variant-ligatures: no-common-ligatures;" class="">).</span><span style="font-variant-ligatures: no-common-ligatures;" class="">fooFunc</span><span style="font-variant-ligatures: no-common-ligatures;" class="">()</span></div></div><div style="margin: 0px; line-height: normal; font-family: Menlo;" class=""><br class=""></div><div style="margin: 0px; line-height: normal;" class="">Will call <font face="Menlo" class="">FooClass</font>’s method implementation</div><div style="margin: 0px; line-height: normal;" class=""><br class=""></div><div style="margin: 0px; line-height: normal;" class="">You can read more about dispatch rules here: <a href="https://medium.com/ios-os-x-development/swift-protocol-extension-method-dispatch-6a6bf270ba94#.hkh1rc56p" class="">https://medium.com/ios-os-x-development/swift-protocol-extension-method-dispatch-6a6bf270ba94#.hkh1rc56p</a></div><div style="margin: 0px; line-height: normal;" class=""><br class=""></div><div style="margin: 0px; line-height: normal; font-family: Menlo;" class=""><br class=""></div><div style="margin: 0px; line-height: normal; font-family: Menlo;" class=""><br class=""></div><div><blockquote type="cite" class=""><div class="">16 нояб. 2016 г., в 4:29, Rick Mann via swift-users <<a href="mailto:swift-users@swift.org" class="">swift-users@swift.org</a>> написал(а):</div><br class="Apple-interchange-newline"><div class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">Okay. I coudln't find official documentation on this, and I don't currently need to do this, but wanted to fully understand it.</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">On Nov 15, 2016, at 17:27 , zh ao <<a href="mailto:owenzx@gmail.com" class="">owenzx@gmail.com</a>> wrote:<br class=""><br class="">'Default' implementation in protocol extension is used as fail safe. You should not consider it like something super class does. If you want it that way, use class inheritance instead.<br class=""><br class="">Zhaoxin<br class=""><br class="">Get Outlook for iOS<br class=""><br class="">_____________________________<br class="">From: Rick Mann via swift-users <<a href="mailto:swift-users@swift.org" class="">swift-users@swift.org</a>><br class="">Sent: 星期三, 十一月 16, 2016 07:51<br class="">Subject: Re: [swift-users] Attempting to call default protocol implementation crashes Playground<br class="">To: Dan Loewenherz <<a href="mailto:dan@lionheartsw.com" class="">dan@lionheartsw.com</a>><br class="">Cc: swift-users <<a href="mailto:swift-users@swift.org" class="">swift-users@swift.org</a>><br class=""><br class=""><br class="">Well, this is a standard protocol default implementation. I was experimenting to see if it was possible to call the default implementation after providing a concrete implementation.<br class=""><br class=""><blockquote type="cite" class="">On Nov 15, 2016, at 14:47 , Dan Loewenherz <<a href="mailto:dan@lionheartsw.com" class="">dan@lionheartsw.com</a>> wrote:<br class=""><br class="">What are you trying to accomplish here, more concretely?<br class=""><br class="">My first thought is that you shouldn't implement the same function in both a protocol extension and a conforming class. Why not just give them different names and call the function from within the extension instead of from the class? E.g.<br class=""><br class="">protocol FooPro {<br class="">func _fooFunc()<br class="">}<br class=""><br class="">extension FooPro {<br class="">func fooFunc() {<br class="">print("fooFunc default")<br class="">_fooFunc()<br class="">}<br class="">}<br class=""><br class="">class FooClass: FooPro {<br class="">func _fooFunc() {<br class="">print("fooFunc FooClass")<br class="">}<br class="">}<br class=""><br class="">let fc = FooClass()<br class="">fc.fooFunc()<br class=""><br class="">Dan<br class=""><br class="">On Tue, Nov 15, 2016 at 4:28 PM, Rick Mann via swift-users <<a href="mailto:swift-users@swift.org" class="">swift-users@swift.org</a>> wrote:<br class="">The following gives Xcode 8.1 a very hard time. Eventually I get a Bad Access on the last line. I'm guessing it's a recursive call. Is there any way to call the default implementation from a "real" implementation?<br class=""><br class="">protocol FooPro<br class="">{<br class="">func fooFunc()<br class="">}<br class=""><br class="">extension FooPro<br class="">{<br class="">func<br class="">fooFunc()<br class="">{<br class="">print("fooFunc default")<br class="">}<br class="">}<br class=""><br class="">class FooClass : FooPro<br class="">{<br class="">func<br class="">fooFunc()<br class="">{<br class="">(self as FooPro).fooFunc()<br class="">print("fooFunc FooClass")<br class="">}<br class="">}<br class=""><br class="">let fc: FooPro = FooClass()<br class="">fc.fooFunc()<br class=""><br class=""><br class="">Thanks!<br class=""><br class=""><br class="">--<br class="">Rick Mann<br class=""><a href="mailto:rmann@latencyzero.com" class="">rmann@latencyzero.com</a><br class=""><br class=""><br class="">_______________________________________________<br class="">swift-users mailing list<br class="">swift-users@swift.org<br class="">https://lists.swift.org/mailman/listinfo/swift-users<br class=""><br class=""></blockquote><br class=""><br class="">--<span class="Apple-converted-space"> </span><br class="">Rick Mann<br class=""><a href="mailto:rmann@latencyzero.com" class="">rmann@latencyzero.com</a><br class=""><br class=""><br class="">_______________________________________________<br class="">swift-users mailing list<br class="">swift-users@swift.org<br class="">https://lists.swift.org/mailman/listinfo/swift-users<br class=""><br class=""><br class=""></blockquote><br style="font-family: Helvetica; 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