> Am 18.05.2016 um 23:17 schrieb Austin Zheng via swift-evolution
> <[email protected]>:
>
> The order does not affect the semantic meaning of the existential. There is a
> section in the proposal on how existentials are conceptually 'reduced' from
> whatever form they take when the programmer types them in, please read it. I
> am not proposing a macro system. The compiler does not do textual replacement
> in order to flatten nested existential definitions.
>
> This is also why it makes no sense to have a generic "Any<T, U>", because
> such a type is identical to "Any<U, T>", which is not true for any other
> generic type or aggregate type in Swift.
Shouldn’t that be a reason to use `any<>` (using a keyword `any`) instead of
`Any<>`? Because `Any<>` would just look like/be a generic type with all normal
expectations, e.g. `Any<T, U>` would *not* be equal to `Any<U, T>` which is
different behavior from `protocol<>`, as I can write
func foo(p: protocol<A, B>) -> protocol<B, A> {
return p
}
-Thorsten_______________________________________________
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