func myBlah(thing interface{}){
switch thing.(type) {
case int:
// handle my int
case string:
// handle my string
default:
// default handling
}
}[0] https://github.com/go-fed/activity/blob/master/streams/gen_t...
// proposed
func Print2(type T1, T2)(s1 []T1, s2 []T2) { ... }
// less noise
func Print2(s1 []'T1, s2 []'T2) { ... }
Beyond mere syntax issues, the semantics of generics itself is adding huge complexity to what is a very capable and accessible 80% language.
I did miss generics when I first started writing Go, but after doing so for about a year at work and 2 years before that, I don't find me missing them at all.
I do not mean this as a criticism of Haskell, but Haskell has a lot of GHC-specific language extensions:
https://downloads.haskell.org/~ghc/latest/docs/html/users_gu...
I am not sure it qualifies as making a choice and standing by it.
> func Print2(s1 []'T1, s2 []'T2) { ... }
where would you add the claim that T1 and T2 must obey some named "contract"?
He asked where you'd denote the contracts each type much obey (e.g. the focus being: in which place, assuming, I guess, that you intent to stray from the current proposal of defining that).
I guess what you can't do by just using the contract name is say that two arguments must be of the same type. Nevermind.
No, T1 and T2 name two generic types to be used in the body, the question is, where do you specify what contract they fulfill?
Eg if we convert an example from the doc to your suggestion:
func SetViaStrings(type To, From viaStrings)(s []From) []To {
func SetViaStrings(s []’From) []’To {
It doesn’t make sense (under this proposal) to replace them with a contract name directly, because the contract in this case takes two type arguments with different expectations of each. You’d need to change the whole proposal such that each contract constrained only a single type, and each function argument could specify potentially a different contract, rather than the current proposal, in which you can only specify one contract that constrains all of the types involved.