def sort_by_perm_nat

bend-mathlib@0.8.1.0 · perm.bend:249

import Base
import bendlib-kernel-list@1.0.0.0/list.bend as K

249# Merge sort permutes a Nat list.
250def sort_by_perm_nat(+xs: List<&2, Nat>) -> K.perm(Nat, xs, sort_by(~Nat, ~Nat.is_le, xs)):
251  sort_by_perm(~Nat, ~Nat.is_le, xs)