> On Jul 6, 2016, at 9:54 AM, Alexey Komnin via swift-users
> <swift-users@swift.org> wrote:
>
> Here is the code:
>
> let a: String = "abc"
> let b: NSString = "abc"
>
> assert(a == b)
> assert(a.hashValue == b.hashValue, "a.hashValue(\(a.hashValue)) !=
> b.hashValue(\(b.hashValue))")
There's no problem if you use generics to select a single Hashable
implementation:
import Foundation
func assertHashableConsistent<T: Hashable>(a: T, b: T) {
assert(a == b, "a and b are equal")
assert(a.hashValue == b.hashValue, "a and b have the same hash
value")
}
assertHashableConsistent(a: "abc" as String, b: "abc" as NSString)
The problem is that, in your case, `a` uses `NSString`'s `Hashable` in the
first line, but `String`'s `Hashable` in the second line. The
`assertHashableConsistent(a:b:)` function, on the other hand, ensures that `a`
uses `NSString`'s `Hashable` in both lines.
--
Brent Royal-Gordon
Architechies
_______________________________________________
swift-users mailing list
swift-users@swift.org
https://lists.swift.org/mailman/listinfo/swift-users
