(motive : Option (Lean.Ident × Lean.TSyntax `arg_val) → Sort u_1) →
  (x : Option (Lean.Ident × Lean.TSyntax `arg_val)) →
    ((x : Lean.Ident) → (v : Lean.TSyntax `arg_val) → motive (some (x, v))) →
      ((x : Option (Lean.Ident × Lean.TSyntax `arg_val)) → motive x) → motive x