David, I'm thinking about the side effects calling a computed property has and although I see some use cases for let properties I also see workarounds. For example, a lazy initialiser will solve the issue of running a certain code only once and caching its value. I also start to think that any case in this proposal will be solved by lazy initialisers thus rendering it unnecessary.
On 17 May 2016 at 17:50, David Sweeris <daveswee...@mac.com> wrote: > You can't, if you're extending a pre-existing type. > > I'd think that it might be possible to do some caching if the compiler > knows that a computed property is constant, but maybe it doesn't work that > way. > > - Dave Sweeris > > On May 17, 2016, at 14:40, Leonardo Pessoa via swift-evolution < > swift-evolution@swift.org> wrote: > > If the value of the property is a constant, shouldn't you just declare it > as one? If you have any sort of computation in it, even concatenating two > constant strings, can you really say this is a constant? And you would also > be overloading the compiler into trying to check for every property you use > let if the overall computation is constant or not. IMO, let isn't really > the most appropriate keyword to use for properties. > > - Leonardo > > On 13 May 2016 at 04:44, Andru Felipe Zuniga via swift-evolution < > swift-evolution@swift.org> wrote: > >> It would be useful for clarification of a computed property being >> constant in extensions. For example: >> >> extension SKSpriteNode { >> static let type: String { >> return “Sprite” >> } >> } >> >> Andru >> >> >> >> _______________________________________________ >> 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 > >
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