Goal:
  
  A : Type
  B : Type
  P : A → B → Type
  Q : A → B → Type
  f : ∀ (x : A) (y : B), P x y → Q x y
  eos : CoreTactics.end_of_section
  fix_0 : ∀ (l : list A) (l' : list B) (a : All2 P l l'),
            map_All2_graph l l' a (map_All2 a)
  ============================
   (∀ (l : list A) (l' : list B) (a : All2 P l l'),
      map_All2_graph l l' a (map_All2 a))


DEBUG:Going to execute:
match goal with
           | H:_ ∧ _ |- _ => destruct H
           | H:_ * _ |- _ => destruct H
           | H:?X → _, H':?X
             |- _ => match X with
                     | _ → _ => specialize (H H')
                     end
           | H:?A ∧ ?B → ?C |- _ => apply (uncurry_conj A B C) in H
           end