<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=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jan 30, 2017, at 3:32 AM, Slava Pestov 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=""><meta http-equiv="Content-Type" content="text/html charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div class=""><blockquote type="cite" class=""><div class="">On Jan 30, 2017, at 1:30 AM, David Sweeris <<a href="mailto:davesweeris@mac.com" class="">davesweeris@mac.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div class=""><blockquote type="cite" class=""><div class="">On Jan 30, 2017, at 1:21 AM, Slava Pestov <<a href="mailto:spestov@apple.com" class="">spestov@apple.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; 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" class=""><div class=""><br class="Apple-interchange-newline">On Jan 30, 2017, at 1:12 AM, David Sweeris 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=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">So I’ve got this code in a package called “SomeLib":<blockquote class="" style="margin: 0px 0px 0px 40px; border: none; padding: 0px;"><div class=""><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">public</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">struct</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span>SomeType {</span></div></div><div class=""><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"> <span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">public</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">var</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span>text =<span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(209, 47, 27);">"SomeText"</span></div></div><div class=""><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;">}</div></div></blockquote><div class="">and then, in another package, write this:</div><blockquote class="" style="margin: 0px 0px 0px 40px; border: none; padding: 0px;"><div class=""><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">import</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span>SomeLib</span></div></div><div class=""><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">print(SomeType().text)</span></div></div></blockquote><div class="">and then run swift build, I get this error:</div><blockquote class="" style="margin: 0px 0px 0px 40px; border: none; padding: 0px;"><div class=""><div class="" style="margin: 0px; line-height: normal; font-family: 'Fira Mono';"><span class="" style="font-variant-ligatures: no-common-ligatures;">error: 'SomeType' initializer is inaccessible due to 'internal' protection level</span></div></div></blockquote><div class="" style="margin: 0px; line-height: normal;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><br class=""></span></div><div class="" style="margin: 0px; line-height: normal;"><span class="" style="font-variant-ligatures: no-common-ligatures;">"Well that’s odd… there isn’t even an initializer to be internal or public”, I said to myself. Then I proceeded to futz around with it for a while before having a lightbulb moment:</span></div><blockquote class="" style="margin: 0px 0px 0px 40px; border: none; padding: 0px;"><div class="" style="margin: 0px; line-height: normal;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">public</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">struct</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span>SomeType {</span></div></span></div><div class="" style="margin: 0px; line-height: normal;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;"> <span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">public</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">var</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span>text =<span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(209, 47, 27);">"SomeText"</span></div></span></div><div class="" style="margin: 0px; line-height: normal;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><div class="" style="margin: 0px; line-height: normal; font-family: Menlo; color: rgb(0, 132, 0);"><span class="" style="font-variant-ligatures: no-common-ligatures;"> <span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">public</span><span class="" style="font-variant-ligatures: no-common-ligatures;"><span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);">init</span><span class="" style="font-variant-ligatures: no-common-ligatures;">() {}<span class="Apple-converted-space"> </span></span><span class="" style="font-variant-ligatures: no-common-ligatures;">//this fixes it</span></div></span></div><div class="" style="margin: 0px; line-height: normal;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><div class="" style="margin: 0px; line-height: normal; font-family: Menlo;"><span class="" style="font-variant-ligatures: no-common-ligatures;">}</span></div></span></div></blockquote><div class="" style="margin: 0px; line-height: normal;"><span class="" style="font-variant-ligatures: no-common-ligatures;"><div class=""><span class="" style="font-variant-ligatures: no-common-ligatures;"><br class=""></span></div><div class=""><span class="" style="font-variant-ligatures: no-common-ligatures;"><br class=""></span></div><div class=""><span class="" style="font-variant-ligatures: no-common-ligatures;">In cases like this where the struct is public and all its stored properties are both public and already have values, should we make the implicit init() function also be public? Seems like the “least surprising” thing to do.</span></div></span></div></div></div></blockquote><div class=""><br class=""></div>This is intentional. I believe the core team’s rationale is that public APIs should always be explicitly written down in source. So your example above defining a public init() is correct.</div></div></blockquote></div><br class=""><div class="">Oh, I knew (well, suspected) it was intentional… I just didn't recall if we’d discussed this specific scenario before. If we did, then I don’t want to rehash it.</div></div></div></blockquote><div class=""><br class=""></div>I think there was a proposal floating around for ‘flexible member-wise initialization’. This would allow explicitly defining an initializer (to make it public or @_inlineable or whatever) without writing out the boilerplate to initialize all members.</div><div class=""><br class=""></div><div class="">I don’t have the link offhand, and I don’t remember what the conclusion was, but if you’re interested you might want to look into it and revive it. ;-)</div></div></div></blockquote><div><br class=""></div><div>I was the author of this proposal. It was deferred. The review brought a lot of good ideas to light so it will look somewhat different when it gets revived. I have been assuming it is out of scope for Phase 1 but plan to revive it when the time comes. </div><div><br class=""></div><div>If this *is* in scope right now please let me know and I’ll find some time to start a new discussion thread outlining two possible directions we could take.</div><br class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><br class=""></div><div class="">Slava</div><div class=""><br class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><br class=""></div><div class="">- Dave Sweeris</div></div></div></blockquote></div><br class=""></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=""></body></html>