(pu : Lean.Compiler.LCNF.Purity) →
  (motive : Unit × Array (Lean.Compiler.LCNF.LetValue pu) → Sort u_1) →
    (x : Unit × Array (Lean.Compiler.LCNF.LetValue pu)) →
      ((fst : Unit) → (res : Array (Lean.Compiler.LCNF.LetValue pu)) → motive (fst, res)) → motive x