shoenig
commented
1 year ago I don't think we can ever rely on non-perfect hashing, at least not while using map under the hood. Unlike some implementations, we have no way of identifying and resolving collisions. First we would need to change the generic parameter type to include an Equal function (making it incompatible with built-in types), and we would also need to implementing chaining for each of the map values - storing values with colliding keys.
Maybe it'll be worth revisiting if the Go team figures out how to make == vs Equal less awkward, but until then we should just keep using map as-is and avoid collisions altogether.
This PR adds HashString(string) and HashParts() helper functions
for computing usable hash values for implementing Hash() functions of
complex struct types.
e.g.
type S struct { A int B string }
func (s *S) Hash() int { return set.HashParts( s.A, set.HashString(B), ) }