<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div></div><div><br></div><div><br>On Jan 10, 2018, at 8:22 AM, Paul Cantrell via swift-evolution <<a href="mailto:swift-evolution@swift.org">swift-evolution@swift.org</a>> wrote:<br><br></div><blockquote type="cite"><div><div class=""><blockquote type="cite" class="">What is your evaluation of the proposal?<br class=""></blockquote><br class=""></div><div class="">+1. Yes please. Long overdue.</div><div class=""><br class=""></div><div class=""><blockquote type="cite" class="">Is the problem being addressed significant enough to warrant a change to Swift?<br class=""></blockquote><div class=""><br class=""></div>It’s a long-standing sore thumb. The proposal’s evidence of community demand fits my own experience: I’ve wanted this on multiple occasions.<br class=""><br class=""></div><div class=""><blockquote type="cite" class="">Does this proposal fit well with the feel and direction of Swift?<br class=""></blockquote><br class=""></div><div class="">Yes, and in particular, on the name bikeshedding:</div><div class=""><br class=""></div><div class="">I favor property names <b class="">with the “all” prefix</b>, whether allValues or allCases. Looking over my own code, I’ve almost always used the word “all” for this when I had to hand-roll it — and either allValues or allCases make reasonable sense in my code when I substitute them.</div><div class=""><br class=""></div><div class="">Whichever protocol name we choose, the property name should be consistent:</div><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>ValueEnumerable → allValues</div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>CaseEnumerable → allCases</div></div></blockquote><div><br></div>this is good point. I think it would be awesome to also have a compile time version named .cases.<div><br></div><div>.allCases would include unknown cases at runtime.</div><div>.cases would only include known at compile time cases. <br><div><div><br></div><br><blockquote type="cite"><div><div class=""></div><div class=""><b class="">Either ValueEnumerable or CaseEnumerable would be a fine name.</b> Contra Chris, I slightly prefer ValueEnumerable, because it extends to situations where we still want to enumerate a fixed set of possibilities which don’t strictly correspond to enum cases but still have that sort of flavor. For example, one might want:</div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #323e7d" class="">enum</span> SideOfBody</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> {</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #323e7d" class="">case</span> left</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #323e7d" class="">case</span> right</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> }</div><div style="margin: 0px; font-stretch: normal; font-size: 12px; line-height: normal; font-family: Helvetica; background-color: rgb(255, 255, 255); min-height: 14px;" class=""><br class=""></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; color: rgb(88, 126, 168); background-color: rgb(255, 255, 255);" class=""><span style="color: #000000" class=""> </span><span style="color: #323e7d" class="">enum</span><span style="color: #000000" class=""> Limb: </span>ValueEnumerable</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> {</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #323e7d" class="">case</span> arm(<span style="color: #587ea8" class="">SideOfBody</span>)</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #323e7d" class="">case</span> leg(<span style="color: #587ea8" class="">SideOfBody</span>)</div><div style="margin: 0px; font-stretch: normal; font-size: 12px; line-height: normal; font-family: Helvetica; background-color: rgb(255, 255, 255); min-height: 14px;" class=""><br class=""></div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #323e7d" class="">static</span> <span style="color: #323e7d" class="">let</span> allValues =</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> [</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #587ea8" class="">arm</span>(.<span style="color: #587ea8" class="">left</span>),</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #587ea8" class="">arm</span>(.<span style="color: #587ea8" class="">right</span>),</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #587ea8" class="">leg</span>(.<span style="color: #587ea8" class="">left</span>),</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> <span style="color: #587ea8" class="">leg</span>(.<span style="color: #587ea8" class="">right</span>)</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> ]</div><div style="margin: 0px; font-stretch: normal; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255);" class=""> }</div></div><div class=""><br class=""></div><div class="">To my eyes, this code reads better than it would with CaseEnumerable / allCases.</div><div class=""><br class=""></div><div class=""><blockquote type="cite" class="">If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?<br class=""></blockquote><br class=""></div><div class="">Java’s enums had this from the beginning, and Josh Bloch’s design for that feature has always worked nicely. Java’s design is slightly different: `Foo.values()` returns Foo[]. However, Swift doesn’t need to follow either that name or type choice: (1) Java doesn’t use the term “case” as Swift does, (2) the “all” prefix better fits Swift’s API guidelines IMO, and (3) using a concrete array type has as opposed to Collection has different implications in Java than it does Swift.</div><div class=""><br class=""></div><div class="">I _do_ agree that the proposal should consider <b class="">constraining the Collection to be Int-indexed</b>. Why should it ever be otherwise? What’s the motivation for leaving that open?</div><div class=""><br class=""></div><div class=""><blockquote type="cite" class="">How much effort did you put into your review? A glance, a quick reading, or an in-depth study?<br class=""></blockquote></div><br class=""><div class="">Medium quick study.</div><div class=""><br class=""></div><div class="">Cheers, P</div><div class=""><br class=""></div></div></blockquote><blockquote type="cite"><div><span>_______________________________________________</span><br><span>swift-evolution mailing list</span><br><span><a href="mailto:swift-evolution@swift.org">swift-evolution@swift.org</a></span><br><span><a href="https://lists.swift.org/mailman/listinfo/swift-evolution">https://lists.swift.org/mailman/listinfo/swift-evolution</a></span><br></div></blockquote></div></div></body></html>