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structure Thms : Thms_sig =


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struct


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type Thm = Thm.thm


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val WFREC_COROLLARY = get_thm WF_Rel.thy "tfl_wfrec"


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val WF_INDUCTION_THM = get_thm WF_Rel.thy "tfl_wf_induct"


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val CUT_LEMMA = get_thm WF_Rel.thy "tfl_cut_apply"

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val CUT_DEF = cut_def


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local val _ = goal HOL.thy "!P x. P x > P (Eps P)"


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val _ = by (strip_tac 1)


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val _ = by (rtac selectI 1)


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val _ = by (assume_tac 1)


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in val SELECT_AX = result()


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end;


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(*


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* A useful congruence rule


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**)


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local val [p1,p2] = goal HOL.thy "(M = N) ==> \


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\ (!!x. ((x = N) ==> (f x = g x))) ==> \


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\ (Let M f = Let N g)";


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val _ = by (simp_tac (HOL_ss addsimps[Let_def,p1]) 1);


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val _ = by (rtac p2 1);


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val _ = by (rtac refl 1);


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in val LET_CONG = result() RS eq_reflection


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end;


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val COND_CONG = if_cong RS eq_reflection;


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fun C f x y = f y x;


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fun prover thl = [fast_tac HOL_cs 1];


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val P = C (prove_goal HOL.thy) prover;


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val eqT = P"(x = True) > x"


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val rev_eq_mp = P"(x = y) > y > x"


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val simp_thm = P"(x>y) > (x = x') > (x' > y)"


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end;
