ProofTree.fin_fst: law of lawful-arrays@0.1.0.0
Import: import lawful-arrays@0.1.0.0/proof_tree.bend as ProofTree
Lines 98-101 of lawful-arrays@0.1.0.0/proof_tree.bend: https://jend.leeeet.dev/read.txt?path=lawful-arrays@0.1.0.0/proof_tree.bend&start_line=98&end_line=101

import Base

law fin_fst:
  for -T: Type
  for r: Array<T> & T
  {Array.set.fin(T, r) == Pair.fst(Array<T>, T, r) : Array<T>}

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array.set.fin
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair.fst
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Sigma