/// If the function object refers to a variable, it's
/// the variable that was visible when the function object
/// was created.  `makeConstN` takes an argument; the
/// function that it returns doesn't.
function makeConstN(n) {
    return function() { return n; }
}

var const10 = makeConstN(10);
log(const10());
log(const10(100));

var const20 = makeConstN(20);
log(const20());
log(const20(100));