Goal:
  
  A : Type
  B : Type
  R : nat → A → B → Type
  H : ∀ (n : nat) (x : A) (y : B), R n x y
  n : nat
  b : B
  l' : list B
  ============================
   (0 = S #|l'| → All2i R n [] (b :: l'))


DEBUG:Going to execute:
discriminate
Level 0: Backtrace:

No primitive equality found.
Level 0: Backtrace:

No primitive equality found.