(motive : Lean.Level × Lean.Expr × Lean.Expr × Lean.Expr → Sort u_1) →
  (__discr : Lean.Level × Lean.Expr × Lean.Expr × Lean.Expr) →
    ((fst : Lean.Level) → (α repr gen : Lean.Expr) → motive (fst, α, repr, gen)) → motive __discr