[(1, 2)].map({ x, y in x + y }) // this line is correct
[(1, 2)].map({ tuple in tuple.0 + tuple.1 }) // this line should not
accepted
or
[(1, 2)].map({ $0 + $1 }) // this line is correct
[(1, 2)].map({ $0.0 + $0.1 }) // this line should not accepted
it's because `((Int, Int)) -> Int` always flatten to `(Int, Int) -> Int`
so, it should only accept the function with two arguments
2017-06-07 11:07 GMT+08:00 Stephen Celis <[email protected]>:
> I like this a lot, but how do we solve for the function case?
>
> func add(_ x: Int, _ y: Int) -> Int {
> return x + y
> }
> [(1, 2)].map(add)
>
> Where does `map` with a function of `((Int, Int)) -> Int` fit in?
>
> > On Jun 6, 2017, at 10:15 PM, Susan Cheng via swift-evolution <
> [email protected]> wrote:
> >
> > Introduction
> >
> >
> > Because the painful of SE-0110, here is a proposal to clarify the tuple
> syntax.
> >
> > Proposed solution
> >
> > 1. single element tuple always be flattened
> >
> > let tuple1: (((Int))) = 0 // TypeOf(tuple1) == Int
> >
> > let tuple2: ((((Int))), Int) = (0, 0) // TypeOf(tuple2) == (Int, Int)
> >
> > 2. function arguments list also consider as a tuple, which means the
> function that accept a single tuple should always be flattened.
> >
> > let fn1: (Int, Int) -> Void = { _, _ in }
> >
> > let fn2: ((Int, Int)) -> Void = { _, _ in } // always flattened
> >
> > let fn3: (Int, Int) -> Void = { _ in } // not allowed, here are two
> arguments
> >
> > let fn4: ((Int, Int)) -> Void = { _ in } // not allowed, here are two
> arguments
> >
> > _______________________________________________
> > swift-evolution mailing list
> > [email protected]
> > https://lists.swift.org/mailman/listinfo/swift-evolution
>
>
_______________________________________________
swift-evolution mailing list
[email protected]
https://lists.swift.org/mailman/listinfo/swift-evolution
