eqBox :: Clos Term -> Clos Term -> Eval ()
--eqBox c c' | c == c' = return ()
eqBox (Var l x,s) (Var l' y,s') =
    do x' <- getId l  x s
       y' <- getId l' y s'
       eq x' y'
eqBox :: Clos Term -> Clos Term -> Eval ()
eqBox (Var l x,s) (Var l' y,s') =
    do x' <- getId l  x s
       y' <- getId l' y s'
       eq x' y'
eqBox (Var l x,s) (Var l' y,s') =
    do x' <- getId l  x s
       y' <- getId l' y s'
       eq x' y'