# HG changeset patch # User nipkow # Date 1529299632 -7200 # Node ID 8dea233d4baedb84124a3cdeb9ab4a9bc7f897b7 # Parent 0eb751466b792142ad25cc99238b54af557a71c4# Parent b047339bd11cc85e2bfa9ada31064934a6d9028b merged diff -r 0eb751466b79 -r 8dea233d4bae src/HOL/Map.thy --- a/src/HOL/Map.thy Sun Jun 17 22:01:16 2018 +0100 +++ b/src/HOL/Map.thy Mon Jun 18 07:27:12 2018 +0200 @@ -133,6 +133,10 @@ by (induction xys) simp_all qed simp +lemma empty_eq_map_of_iff [simp]: + "empty = map_of xys \ xys = []" +by(subst eq_commute) simp + lemma map_of_eq_None_iff: "(map_of xys x = None) = (x \ fst ` (set xys))" by (induct xys) simp_all diff -r 0eb751466b79 -r 8dea233d4bae src/HOL/Option.thy --- a/src/HOL/Option.thy Sun Jun 17 22:01:16 2018 +0100 +++ b/src/HOL/Option.thy Mon Jun 18 07:27:12 2018 +0200 @@ -36,6 +36,9 @@ lemma not_Some_eq [iff]: "(\y. x \ Some y) \ x = None" by (induct x) auto +lemma comp_the_Some[simp]: "the o Some = id" +by auto + text \Although it may appear that both of these equalities are helpful only when applied to assumptions, in practice it seems better to give them the uniform iff attribute.\