# HG changeset patch # User huffman # Date 1231832190 28800 # Node ID b2cfb5d0a59e1c8874727dbfb2e2fea043b98eb8 # Parent c0d225a7f6ff5479ebd969af546b38d39c1fd2ed change dvd_minus_iff, minus_dvd_iff from [iff] to [simp] (due to problems with Library/Primes.thy) diff -r c0d225a7f6ff -r b2cfb5d0a59e src/HOL/Ring_and_Field.thy --- a/src/HOL/Ring_and_Field.thy Mon Jan 12 22:41:08 2009 -0800 +++ b/src/HOL/Ring_and_Field.thy Mon Jan 12 23:36:30 2009 -0800 @@ -295,7 +295,7 @@ subclass ring_1 .. subclass comm_semiring_1_cancel .. -lemma dvd_minus_iff [iff]: "x dvd - y \ x dvd y" +lemma dvd_minus_iff [simp]: "x dvd - y \ x dvd y" proof assume "x dvd - y" then have "x dvd - 1 * - y" by (rule dvd_mult) @@ -306,7 +306,7 @@ then show "x dvd - y" by simp qed -lemma minus_dvd_iff [iff]: "- x dvd y \ x dvd y" +lemma minus_dvd_iff [simp]: "- x dvd y \ x dvd y" proof assume "- x dvd y" then obtain k where "y = - x * k" ..