law drop_succ_sym

bend-mathlib@0.8.1.0 · list.bend:3165

import Base

3165# Dropping n + 1 elements of a cons drops its head and n from its tail, reversed to rewrite toward the simple side.
3166law drop_succ_sym:
3167  for -a: Quant
3168  for -A: Kind(a)
3169  for -x: A
3170  for -xs: List<a, A>
3171  for -n: Nat
3172  {List.drop(a, A, xs, n) == List.drop(a, A, x <> xs, 1n+n) : List<a, A>}