[Proposal] CEP 1: context managers and “with” statement

[shdown]

“Хожу к себе с докладом,
Воззвания пишу…” — М.Щ.

fun RestoreScope(n) {
    f := nil
    fun f(dict) {
        Scale(dict.n)
    }
    return {"_enter_func": nil, "_exit_func": f, "n": n}
}

fun foo(a, b, s) {
    old_s := Scale()
    with (RestoreScope(old_s)) {
        Scale(s)
        return a / b
    }
}