I like this idea - never came up to me before n * fac(n-1) vs. * n fac(- n 1) or * (n, fac(n-1)) as a method call, which makes it clear * is the last function

I like this idea - never came up to me before n * fac(n-1) vs. * n fac(- n 1) or * (n, fac(n-1)) as a method call, which makes it clear * is the last function that's called.