# HG changeset patch # User bulwahn # Date 1328428033 -3600 # Node ID 92b629f568c4786bd5c0e42348309367998a8ecb # Parent e139d0e29ca11426f1c5086579520bf1d4cba871 removing lemma bij_betw_Disj_Un, as it is a special case of bij_between_combine (was added in d1fc454d6735, and has not been used since) diff -r e139d0e29ca1 -r 92b629f568c4 src/HOL/Fun.thy --- a/src/HOL/Fun.thy Sun Feb 05 08:36:41 2012 +0100 +++ b/src/HOL/Fun.thy Sun Feb 05 08:47:13 2012 +0100 @@ -427,28 +427,6 @@ using * by blast qed -(* FIXME: bij_betw_Disj_Un is special case of bij_betw_combine -- should be removed *) -lemma bij_betw_Disj_Un: - assumes DISJ: "A \ B = {}" and DISJ': "A' \ B' = {}" and - B1: "bij_betw f A A'" and B2: "bij_betw f B B'" - shows "bij_betw f (A \ B) (A' \ B')" -proof- - have 1: "inj_on f A \ inj_on f B" - using B1 B2 by (auto simp add: bij_betw_def) - have 2: "f`A = A' \ f`B = B'" - using B1 B2 by (auto simp add: bij_betw_def) - hence "f`(A - B) \ f`(B - A) = {}" - using DISJ DISJ' by blast - hence "inj_on f (A \ B)" - using 1 by (auto simp add: inj_on_Un) - (* *) - moreover - have "f`(A \ B) = A' \ B'" - using 2 by auto - ultimately show ?thesis - unfolding bij_betw_def by auto -qed - lemma bij_betw_subset: assumes BIJ: "bij_betw f A A'" and SUB: "B \ A" and IM: "f ` B = B'"