U32alg.assoc: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/proofs/lib/u32alg.bend as U32alg
Lines 281-284 of bend-collections-laws-math@1.0.0.0/proofs/lib/u32alg.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/u32alg.bend&start_line=281&end_line=284

import Base

def assoc(+a: U32, +b: U32, +c: U32) -> {U32.add(U32.add(a, b), c) == U32.add(a, U32.add(b, c)) : U32}:
  match a b c:
    case U32{x} U32{y} U32{z}:
      Equal.cong(Word(32n), U32, w => U32{w}, Word.add(32n, Word.add(32n, x, y), z), Word.add(32n, x, Word.add(32n, y, z)), w_assoc(32n, x, y, z))

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.cong
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Word
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Word.add
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/u32alg.bend&name=w_assoc