I don’t think it’s that uncommon. Let’s say you have a function that handles a request. A common use case is to add permission checks before applying that function. You can write a generic permission check a bit like this:
func NeedsPermission(f func(Request) (Response, error), perm string) func(Request) (Response, error) {
return func(r Request) (Response, error) {
if !check(r, perm) {
return nil, NewPermError(perm)
}
return f(r)
}
}
// elsewhere
Bar := NeedsPermission(Foo, "superman")
This would allow you to separate the permission check logic from the business logic. Though to be fair, in Go they prefer to keep things as simple as possible but it’s just to illustrate that these concepts are not that alien.
True, but that requires writing an additional definition and hides the parameter types, which can be very interesting, and you’d need a typedef for every new param combination I guess. It feels like a solution for a problem that could have been avoided by a better signature syntax in the first place.