law last_append_singleton_sym

bend-mathlib@0.8.1.0 · list.bend:2972

import Base

2972# The last element of xs ++ [x] is x, reversed to rewrite toward the simple side.
2973law last_append_singleton_sym:
2974  for -a: Quant
2975  for -A: Kind(a)
2976  for xs: List<a, A>
2977  for -x: A
2978  {Some{x} == List.last(a, A, List.append(a, A, xs, [x])) : Maybe<a, A>}