"Continuation" already means something else in computer programming. I would suggest you find another term.
https://en.wikipedia.org/wiki/Continuation > On Oct 30, 2017, at 6:12 PM, Mike Kluev via swift-evolution > <swift-evolution@swift.org> wrote: > > a general feeling that there are two very different use cases of extensions > -- one to extend own classes and another to extend other people classes; a > lengthy discussion in a nearby thread; a disparity of features of class and > it's extensions and different access right treatment depending upon whether > the extension is in the same with the main class or a different file lead me > to the following idea. hopefully you will find this idea useful and we may > even see it one day in swift. > > introducing class / struct / enum continuations. > > in a few words the are: > > 1) "extensions on steroids". in fact very similar to Objective-C "class > extensions" but can be more than one and in more than one file. > > 2) as good as the classes they continue (or other continuations they continue) > > 3) can declare variables > > 4) have full access to "private" members of the class or other continuations > regardless whether they are in the same or in a different files. no need for > "public/internal/module" fallbacks to pass though files boundaries. similarly > the class itself can use private members of its continuations. > > 5) "by invitation only" system. can only be written if declared by the class > or some continuation of it. > > 6) A particular continuation only defined once (of course). There can be an > arbitrary number of different continuations to a class similar to extensions. > > 7) alternative name considered: "extending" (as a noun). shall definitely be > a different name than say, "extension" with some bracket-syntax variation - > the two use cases are very different and shall be named differently. > > 8) the particular syntax is preliminary of course. > > example: > > ============= Some.swift ================== > > class Some { > > private func private_method_of_class() { > > // *** can use private methods of continuations even if they are in a > different file > private_method_defined_in_a_continuation() > } > > // *** "by invitation" system > > continuation Feature // *** declaring a continuation > continuation SomethingElse // *** Capitalized names, like classes > } > > ============= Some-Feature.swift ================== > > // *** similar naming convetion to "Some+Feature.swift" > // used for extensions, just with "-" instead > > // *** this is merely a naming convention, no need to > necessarily follow it, can put more than one thing into > a file, the continuation can reside in the same file as > the main class fie, etc. > > continuation Feature of Some { > > // *** as good as class itself. first-class citizen > // *** same syntax can be used for structs and enums > > var x: Int // *** can declare variables > > private func private_method_defined_in_a_continuation() { > private_method_of_class() > > // *** can use private methods of the class or of other > continuations even if they are in a different file > } > > // *** continuations are as good as classes and can > // *** declare other continuations if needed > > continuation CanDoThis > } > > ============= Any file ================== > > continuation Feature of Some { // *** error, continuation is already defined > } > > continuation Other of Some { // *** error: Other is not a continuation of Some > } > > thoughts? > > Mike > > _______________________________________________ > swift-evolution mailing list > swift-evolution@swift.org > https://lists.swift.org/mailman/listinfo/swift-evolution _______________________________________________ swift-evolution mailing list swift-evolution@swift.org https://lists.swift.org/mailman/listinfo/swift-evolution
