Goal:
  
  T : Type
  Listable_T : Listable T
  FinitelyListable_T : FinitelyListable T
  x : T
  y : T
  ============================
   (eqb_of_listable x y = true <-> x = y ->
    reflectProp (x = y) (eqb_of_listable x y))


DEBUG:Going to execute:
case : eqb_of_listable 
DEBUG LTAC Evaluated term: (eqb_of_listable_eq x y)