Goal:
    x : t  y : t  H : lt y x  H0 : lt x y
  ============================
   (Gt = Lt)


DEBUG:Going to execute:
now apply irreflexivity in H0
DEBUG LTAC Evaluated term: irreflexivity
Level 0: Backtrace:

Unable to apply lemma of type "Reflexive (complement ?R)"
on hypothesis of type "lt y x".
Level 0: Backtrace:

Unable to apply lemma of type "Reflexive (complement ?R)"
on hypothesis of type "lt y x".
Level 0: Backtrace:

Unable to apply lemma of type "Reflexive (complement ?R)"
on hypothesis of type "lt y x".
Level 0: Backtrace:

Unable to apply lemma of type "Reflexive (complement ?R)"
on hypothesis of type "lt y x".