> On 7 May 2017, at 10:30, Xiaodi Wu <[email protected]> wrote:
>
> Sorry, I'm confused: what is the point of adding a method that does the same
> thing as an existing free function? With one-sided ranges now a part of the
> language, I'd support removal of `enumerated()` with no other changes.
I’m talking about scenario where you have a chain of sequence operations, say:
(1...N).makeIterator().enumerated().lazy.prefix(while: {$0.0 < oneLess}).count()
With a free function, you need to break the chain in order to replace
enumerated with zip:
zip((1...N).makeIterator(), 0...oneLess).lazy.prefix(while: {$0.0 <
oneLess}).count()
It forces you to rearrange your code into less than ideal order. Free function
zip works great if you start with it. Not when you need to employ it in the
middle of the chain.
(1...N).makeIterator().zipped(with: 0...oneLess).lazy.prefix(while: {$0.0 <
oneLess}).count()
Just to be clear, how much change I’m proposing here, in case we remove
enumerated:
extension Sequence {
func zipped<S>(with otherSequence: S) -> Zip2Sequence<Self, S> where S:
Sequence {
return zip (self, otherSequence)
}
}
Best regards
Pavol Vaskovic _______________________________________________
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