Algebra.op_comm3_sym: law of bend-mathlib@0.8.1.0
Import: import bend-mathlib@0.8.1.0/algebra.bend as Algebra
Lines 351-359 of bend-mathlib@0.8.1.0/algebra.bend: https://jend.leeeet.dev/read.txt?path=bend-mathlib@0.8.1.0/algebra.bend&start_line=351&end_line=359

import Base

# Three-way commutation from commutativity alone, reversed to rewrite toward the simple side.
law op_comm3_sym:
  for ~A: Data
  for ~op: A -> A -> A
  for ~comm: @x: A -> @y: A -> {op(x, y) == op(y, x) : A}
  for +a: A
  for +b: A
  for +c: A
  {op(c, op(b, a)) == op(op(a, b), c) : A}

Uses (2):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=bend-mathlib@0.8.1.0/algebra.bend&name=op_comm3