def perm
import bend-collections-laws-math@1.0.0.0/src/math/generic.bend as Genericimport Base
import bend-collections-laws-math@1.0.0.0/src/math/num.bend as N
478def perm(~T: Data, ~op: N.Op<T> -> T, ~test: N.Test<T> -> Bool, +n: T, +k: T) -> Result<&2, &2, N.NumError, T>:
479 perm_big(~T, ~op, ~test, n, k, test(N.Lt{n, k}))