BendMlNatLemmas.append_assoc: law of bend-ml-nat-lemmas@0.1.2.0
Import: import bend-ml-nat-lemmas@0.1.2.0/main.bend as BendMlNatLemmas
Lines 242-247 of bend-ml-nat-lemmas@0.1.2.0/main.bend: https://jend.leeeet.dev/read.txt?path=bend-ml-nat-lemmas@0.1.2.0/main.bend&start_line=242&end_line=247

import Base

law append_assoc:
  for -A: Data
  for  xs: List<&2, A>
  for  ys: List<&2, A>
  for  zs: List<&2, A>
  {List.append(&2, A, List.append(&2, A, xs, ys), zs) == List.append(&2, A, xs, List.append(&2, A, ys, zs)) : List<&2, A>}

Uses (2):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.append