I don't know why most examples about the Go iterators shows unnecessarily convoluted examples. The authors probably don't know as much of the language as they think they do.

Go is far from perfect and certainly has a lot of flaws, but IMO the iterators design fits well into the language and does not deserve the criticism.

The range only needs a function, so what is the point of calling a function that returns a function?

This is enough to make a range iterator, you don't have to call `All` manually:

    func (slice Slice) All(yield func(string) bool) {
        for _, s := range slice {
            if !yield(s) {
                break
            }
        }
    }

https://go.dev/play/p/7AYOXzlHU4t?v=gotip

In Go, the expression `object.method` already returns the method as a function, with `object` being already bound in the scope of the function. The syntax is so that if you have this definition:

    type T string
    func (t T) f(a int) int {
        return a
    }

Then:

- `T.f` returns `func(t T, a int) int`

- `T("whatever").f` returns `func(a int) int` where `t` is already set to `"whatever"`

- `T("whatever").f(42)` calls the function and returns `42`