Goal:
  
  A : Type
  P : nat → A → Type
  p : nat → A → bool
  n : nat
  Hp : ∀ (i : nat) (x : A), reflectT (P i x) (p i x)
  H : is_true true
  ============================
   (locked false = true)


DEBUG:Going to execute:
Ltac.assumption
DEBUG LTAC Evaluated term: not_locked_false_eq_true