On: A Proposal for Adding Generics to Go

[jrockway]

That ship already sailed with widespread misuse of interfaces. Consider:

    package foo

    type T interface { func Bar() }

    func New() T {
       return &someotherpackage.ImplPickedAtRuntime{...}
    }

Now whenever you see:

    x := foo.New()
    x.Bar()

You have no idea where to read the code for Bar. For maximum fun, ImplPickedAtRuntime should then contain members that were allocated in the same way. What should be a simple M-. then eats up your entire afternoon.