Conform C++ types that have a std::hash overload to Swift.Hashable

[egorzhdan]

We could consider synthesizing a Hashable conformance for some C++ types:

extension MyCppType : Hashable {
  func hash(into hasher: inout Hasher) {
    hasher.combine(std.hash<MyCppType>(self))
  }
}

Note that Swift.Hashable inherits from Swift.Equatable, so we'd have to conform these types to Swift.Equatable as well.

[vmk8826]

Can you assign this to me?

[egorzhdan]

@vmk8826 sure, please feel free to try to tackle this, and don't hesitate to ask questions.

[ktoso]

Radar-ified rdar://111879435