List.replicate_add: law of bend-mathlib@0.8.1.0
Import: import bend-mathlib@0.8.1.0/list.bend as List
Lines 1339-1345 of bend-mathlib@0.8.1.0/list.bend: https://jend.leeeet.dev/read.txt?path=bend-mathlib@0.8.1.0/list.bend&start_line=1339&end_line=1345

import Base

# Replicating m + n times appends m copies to n copies.
law replicate_add:
  for -A: Data
  for m: Nat
  for -n: Nat
  for -x: A
  {List.replicate(A, Nat.add(m, n), x) == List.append(&2, A, List.replicate(A, m, x), List.replicate(A, n, x)) : List<&2, A>}

Uses (5):
  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
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.replicate
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add