law map_id

bend-mathlib@0.8.1.0 · list.bend:1288

import Base

1288# Mapping the identity gives the list back.
1289law map_id:
1290  for ~A: Type
1291  for xs: List<A>
1292  {List.map(~A, ~A, ~(x => x), xs) == xs : List<A>}