(motive : Lean.Expr × Option Lean.Expr × Lean.Elab.Tactic.Do.FVarUses → Sort u_1) →
  (__discr : Lean.Expr × Option Lean.Expr × Lean.Elab.Tactic.Do.FVarUses) →
    ((ty : Lean.Expr) → (val? : Option Lean.Expr) → (fvs : Lean.Elab.Tactic.Do.FVarUses) → motive (ty, val?, fvs)) →
      motive __discr