[swift-evolution] Reduce with inout

[Freak Show]

Am I the only one who finds this incredibly ugly and hard to read?

This is more or less solved by inject:into: idiom.  There is no reason for inout for this particular problem.


> On Jan 24, 2017, at 06:43, Gwendal Roué via swift-evolution <swift-evolution at swift.org> wrote:
> 
> But what if we stop fighting? Isn't the following code the correct version of Chris's vision ?
> 
> extension Sequence {
>     func reduce<A>(mutating result: inout A, _ combine: (inout A, Iterator.Element) -> ()) {
>         for element in self {
>             combine(&result, element)
>         }
>     }
> }
> 
> extension Sequence where Iterator.Element: Equatable {
>     func uniq() -> [Iterator.Element] {
>         var result: [Iterator.Element] = [] // meh
>         reduce(mutating: &result) { (result: inout [Iterator.Element], element) in
>             if result.last != element {
>                 result.append(element)
>             }
>         }
>         return result
>     }
> }
> 
> let x = [1, 1, 2, 3]
> x.uniq() // [1, 2, 3]

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