As an alternative, could we require the parens on the return. For example: (Int) -> (Float) (String) -> () () -> () () -> (Double)
This looks cleaner, improves consistency, and simplifies the syntax (i.e., no need to remember when parens are necessary). -Patrick > On Apr 15, 2016, at 1:38 PM, Chris Lattner via swift-evolution > <swift-evolution@swift.org> wrote: > > >> On Apr 15, 2016, at 5:11 AM, David Hart <da...@hartbit.com> wrote: >> >> If the original rationale is gone, shouldn’t we also get rid of the empty >> tuple-type and replace it by a full-blown Void instead of Void being a >> typealis for the empty tuple? > > This could be done, but it would make the language larger and less > consistent. It would require introducing a new concept (a first class Void > type). Further, at some point we may have the ability to define algorithms > over arbitrary width tuples (e.g. perhaps like C++ variadic templates) and > that benefits from having the empty tuple as a base case. > > -Chris > > >> (Int) -> Float >> (String) -> Void >> () -> Void >> () -> Double >> >> It looks more consistent to me. >> >>> On 15 Apr 2016, at 06:57, Chris Lattner via swift-evolution >>> <swift-evolution@swift.org> wrote: >>> >>> We currently accept function type syntax without parentheses, like: >>> >>> Int -> Float >>> String -> () >>> >>> etc. The original rationale aligned with the fact that we wanted to treat >>> all functions as taking a single parameter (which was often of tuple type) >>> and producing a tuple value (which was sometimes a tuple, in the case of >>> void and multiple return values). However, we’ve long since moved on from >>> that early design point: there are a number of things that you can only do >>> in a parameter list now (varargs, default args, etc), implicit tuple splat >>> has been removed, and the compiler has long ago stopped modeling function >>> parameters this way. Beyond that, it eliminates one potential style war. >>> >>> Given all this, I think it makes sense to go for syntactic uniformity >>> between parameter list and function types, and just require parenthesis on >>> the argument list. The types above can be trivially written as: >>> >>> (Int) -> Float >>> (String) -> () >>> >>> Thoughts? >>> >>> -Chris >>> _______________________________________________ >>> 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 _______________________________________________ swift-evolution mailing list swift-evolution@swift.org https://lists.swift.org/mailman/listinfo/swift-evolution
