ProofList.pieces_length: law of lawful-fields@0.1.1.0
Import: import lawful-fields@0.1.1.0/proof_list.bend as ProofList
Lines 425-429 of lawful-fields@0.1.1.0/proof_list.bend: https://jend.leeeet.dev/read.txt?path=lawful-fields@0.1.1.0/proof_list.bend&start_line=425&end_line=429

import Base
import lawful-fields@0.1.1.0/defs.bend as F

law pieces_length:
  for +es: List<&2, U32>
  for +xs: List<&2, U32>
  for +from: Nat
  {List.length(&2, List<&2, U32>, F.pieces(es, xs, from)) == List.length(&2, U32, es) : Nat}

Uses (7):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.length
  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
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.to_nat
  https://jend.leeeet.dev/definition.txt?path=lawful-fields@0.1.1.0/defs.bend&name=pieces