<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="">Sorry if my original reply didn’t come across as neutral as I had hoped. I actually like the Protocol suffix and have used it when the name I wanted to use was already taken by a concrete type. </div><div class=""><br class=""></div><div class="">I’m not sure yet if a Protocol suffix would “always” be the right choice when a protocol can't be named with a noun, or with an `able`, `ible`, or `ing` suffix. There might not be that many cases. </div><div class=""><br class=""></div><div class="">How about a guideline that only covers the case when a protocol coexists with a concrete type? Maybe something like:</div><div class=""><br class=""></div><div class=""> + When a protocol and a concrete type contest for the same name, the protocol should be named using the suffix `Protocol` (e.g. `IteratorProtocol`).</div><div class=""><br class=""></div><div class="">That would both apply to the Range protocol naming, and would follow the the established pattern set by IteratorProtocol, LazySequenceProtocol which seem to have come from [SE-0006](<a href="https://github.com/apple/swift-evolution/blob/master/proposals/0006-apply-api-guidelines-to-the-standard-library.md" class="">https://github.com/apple/swift-evolution/blob/master/proposals/0006-apply-api-guidelines-to-the-standard-library.md</a>):</div><div class=""><br class=""></div><div class="">> Strip `Type` suffix from protocol names. In a few special cases this means adding a `Protocol` suffix to get out of the way of type names that are primary (though most of these we expect to be obsoleted by Swift 3 language features).</div><div class=""><br class=""></div><div class="">David</div><br class=""><div><blockquote type="cite" class=""><div class="">On 20 Apr 2017, at 18:55, Jordan Rose <<a href="mailto:jordan_rose@apple.com" class="">jordan_rose@apple.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="" applecontenteditable="true"><div class="">Yeah, I wasn't trying to take a side, just identifying where David might have heard "Protocol" in an official Apple presentation. I'm staying out of this one. :-)</div><div class=""><br class=""></div><div class="">Jordan</div><br class=""><div class=""><blockquote type="cite" class=""><div class="">On Apr 20, 2017, at 00:21, Gwendal Roué <<a href="mailto:gwendal.roue@gmail.com" class="">gwendal.roue@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="content-type" content="text/html; charset=utf-8" class=""><div dir="auto" class=""><div class=""></div><div class="">Well, IteratorProtocol, LazySequenceProtocol weren't imported from ObjC.</div><div class=""><br class=""></div><div class="">They set a precedent for the -Protocol suffix.</div><div class=""><br class=""></div><div class="">Now, even if you don't like RangeProtocol, this doesn't make RangeExpression better.</div><div class=""><br class=""></div><div class="">"Expression" and `1...` don't belong to the same level of the language: one is a concept of that belongs to the compiler, when the other is a plain value used in a program:</div><div class=""><br class=""></div><div class="">When a program does `1 + 2`, it both sums two integers, and builds a expression from two other expressions and an operator. Both are true. Yet 1 is of type `Integer`, not `IntegerExpression`.</div><div class=""><br class=""></div><div class="">Currently all types of the standard library belong the program realm, not to the compiler realm. I wish we wouldn't break this practice, and avoid `RangeExpression`.</div><div class=""><br class=""></div><div class="">That's why I suggest `RangeProtocol`. Other options could be `Ranging`, `Bounds`...</div><div class=""><br class=""></div><div class="">Gwendal Roué</div><div class=""><br class=""></div><div class=""><br class="">Le 19 avr. 2017 à 23:35, Jordan Rose <<a href="mailto:jordan_rose@apple.com" class="">jordan_rose@apple.com</a>> a écrit :<br class=""><br class=""></div><blockquote type="cite" class=""><div class=""><meta http-equiv="Content-Type" content="text/html charset=utf-8" class=""><div class="">That was probably about the ObjC importer, which does this (appends "Protocol") when there's a class and protocol with the same name in the same module. That doesn't necessarily mean it's the right thing to put in the API guidelines, though.</div><div class=""><br class=""></div><div class="">Jordan</div><div class=""><br class=""></div><br class=""><div class=""><blockquote type="cite" class=""><div class="">On Apr 19, 2017, at 10:59, Gmail 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=""><div class="">I seem to recall that something (maybe a WWDC session) mentioned something about protocols that in essence represent a single type would have the Protocol-suffix. </div><div class=""><br class=""></div><div class="">Unfortunately I couldn’t find it (yet?). The closest I’ve found so far is <a href="http://asciiwwdc.com/2014/sessions/407" class="">http://asciiwwdc.com/2014/sessions/407</a> but I’m not sure that was it.</div><div class="">> essentially when there's a conflict between a class name and a protocol name, we'll append protocol to the name of the protocol.</div><div class=""><br class=""></div><div class="">David</div><br class=""><div class=""><blockquote type="cite" class=""><div class="">On 19 Apr 2017, at 17:55, Gwendal Roué 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=""><br class=""><blockquote type="cite" class="">Le 19 avr. 2017 à 17:23, Gwendal Roué <<a href="mailto:gwendal.roue@gmail.com" class="">gwendal.roue@gmail.com</a>> a écrit :<br class=""><br class="">Re: [swift-evolution] [Review] SE-0172: One-sided Ranges<br class=""><br class="">"RangeExpression" is an unexpected name. I was expecting "RangeProtocol", as in IteratorProtocol and LazySequenceProtocol. We need a consistent suffix for protocols that can't be named in -able, -ible, or named with a simple noun because the noun is already used by a concrete type. "-Protocol" should be that prefix: RangeProtocol.<br class=""></blockquote><br class="">A detailed look at API Design Guidelines [1] shows that this subject is not addressed:<br class=""><br class=""><blockquote type="cite" class=""><span class="Apple-tab-span" style="white-space:pre"> </span>• Protocols that describe what something is should read as nouns (e.g. `Collection`).<br class=""><span class="Apple-tab-span" style="white-space:pre"> </span>• Protocols that describe a capability should be named using the suffixes `able`, `ible`, or `ing` (e.g. `Equatable`, `ProgressReporting`).<br class=""></blockquote><br class="">Nothing is said for "protocols that describe what something but can't be named as nouns", or "protocols that describe a capability but can't be named using the suffixes able, ible, or ing".<br class=""><br class="">For example: the name of the protocol for all ranges discussed with SE-0172 should be addressed by the first rule (because the protocol describes what something is rather than a capability). But that protocol can't be named Range because Range is already taken.<br class=""><br class="">Such a situation comes rather easily:<br class=""><br class="">- in an evolving code base, when a protocol is added on top of an existing type hierarchy which should be preserved (RangeProtocol added on top of Range, ClosedRange, etc.)<br class="">- at the birth of a code base, when a protocol coexists with a concrete type which rightfully deserves the noun claimed by the protocol.<br class=""><br class="">IteratorProtocol and LazySequenceProtocol have set a precedent: maybe we should have the API Design Guidelines evolve with a third rule:<br class=""><br class="">+ When a protocol can't be named with a noun, or with an `able`, `ible`, or `ing` suffix, the protocol should be named using the suffix `Protocol` (e.g. `IteratorProtocol`).<br class=""><br class="">What do you think?<br class=""><br class="">Gwendal Roué<br class="">[1] <a href="https://swift.org/documentation/api-design-guidelines/" class="">https://swift.org/documentation/api-design-guidelines/</a><br class=""><br class="">_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><br class=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class=""></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=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class=""></div></blockquote></div><br class=""></div></blockquote></div></div></blockquote></div><br class=""></div></div></blockquote></div><br class=""></body></html>