[swift-evolution] [Swift 3?] Add ContiguousArray -> Array non-copying initialiser

[Dmitri Gribenko]

On Wed, Jul 27, 2016 at 11:08 PM, Karl via swift-evolution
<swift-evolution at swift.org> wrote:
> It seems like a reasonably large hole with a simple fix. Going from
> ContiguousArray to Array is a kind-of upcasting conversion and should be
> allowed -- it seems like that's almost the whole point of the type.

Hi Karl,

Converting a ContiguousArray to Array using Array's initializer is
O(1).  Are you seeing something different?

Array.init:

https://github.com/apple/swift/blob/f8f6d61d195185f54aeba425dd0db8be4c5d163f/stdlib/public/core/Arrays.swift.gyb#L1037

ContiguousArray._copyToContiguousArray():

https://github.com/apple/swift/blob/f8f6d61d195185f54aeba425dd0db8be4c5d163f/stdlib/public/core/Arrays.swift.gyb#L1430

Dmitri

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