Goal:
    A : Type  B : Type  R : A → B → Prop  R' : A → B → Prop
  ============================
   (Forall2 R' [] [] → Forall2 (λ (x : A) (y : B), R x y ∧ R' x y) [] [])


DEBUG:Going to execute:
<coq-core.plugins.ltac::intro@0>