Separation_Algebra/Map_Extra.thy
changeset 25 a5f5b9336007
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Separation_Algebra/Map_Extra.thy	Sat Sep 13 10:07:14 2014 +0800
@@ -0,0 +1,573 @@
+(* Author: Rafal Kolanski, 2008
+   Maintainers: Gerwin Klein <kleing at cse.unsw.edu.au>
+                Rafal Kolanski <rafal.kolanski at nicta.com.au>
+*)
+
+header {* More properties of maps plus map disjuction. *}
+
+theory Map_Extra
+  imports Main
+begin
+
+text {*
+  A note on naming:
+  Anything not involving heap disjuction can potentially be incorporated
+  directly into Map.thy, thus uses @{text "m"} for map variable names.
+  Anything involving heap disjunction is not really mergeable with Map, is
+  destined for use in separation logic, and hence uses @{text "h"}
+*}
+
+section {* Things that could go into Option Type *}
+
+text {* Misc option lemmas *}
+
+lemma None_not_eq: "(None \<noteq> x) = (\<exists>y. x = Some y)" by (cases x) auto
+
+lemma None_com: "(None = x) = (x = None)" by fast
+
+lemma Some_com: "(Some y = x) = (x = Some y)" by fast
+
+
+section {* Things that go into Map.thy *}
+
+text {* Map intersection: set of all keys for which the maps agree. *}
+
+definition
+  map_inter :: "('a \<rightharpoonup> 'b) \<Rightarrow> ('a \<rightharpoonup> 'b) \<Rightarrow> 'a set" (infixl "\<inter>\<^isub>m" 70) where
+  "m\<^isub>1 \<inter>\<^isub>m m\<^isub>2 \<equiv> {x \<in> dom m\<^isub>1. m\<^isub>1 x = m\<^isub>2 x}"
+
+text {* Map restriction via domain subtraction *}
+
+definition
+  sub_restrict_map :: "('a \<rightharpoonup> 'b) => 'a set => ('a \<rightharpoonup> 'b)" (infixl "`-"  110)
+  where
+  "m `- S \<equiv> (\<lambda>x. if x \<in> S then None else m x)"
+
+
+subsection {* Properties of maps not related to restriction *}
+
+lemma empty_forall_equiv: "(m = empty) = (\<forall>x. m x = None)"
+  by (fastforce intro!: ext)
+
+lemma map_le_empty2 [simp]:
+  "(m \<subseteq>\<^sub>m empty) = (m = empty)"
+  by (auto simp: map_le_def intro: ext)
+
+lemma dom_iff:
+  "(\<exists>y. m x = Some y) = (x \<in> dom m)"
+  by auto
+
+lemma non_dom_eval:
+  "x \<notin> dom m \<Longrightarrow> m x = None"
+  by auto
+
+lemma non_dom_eval_eq:
+  "x \<notin> dom m = (m x = None)"
+  by auto
+
+lemma map_add_same_left_eq:
+  "m\<^isub>1 = m\<^isub>1' \<Longrightarrow> (m\<^isub>0 ++ m\<^isub>1 = m\<^isub>0 ++ m\<^isub>1')"
+  by simp
+
+lemma map_add_left_cancelI [intro!]:
+  "m\<^isub>1 = m\<^isub>1' \<Longrightarrow> m\<^isub>0 ++ m\<^isub>1 = m\<^isub>0 ++ m\<^isub>1'"
+  by simp
+
+lemma dom_empty_is_empty:
+  "(dom m = {}) = (m = empty)"
+proof (rule iffI)
+  assume a: "dom m = {}"
+  { assume "m \<noteq> empty"
+    hence "dom m \<noteq> {}"
+      by - (subst (asm) empty_forall_equiv, simp add: dom_def)
+    hence False using a by blast
+  }
+  thus "m = empty" by blast
+next
+  assume a: "m = empty"
+  thus "dom m = {}" by simp
+qed
+
+lemma map_add_dom_eq:
+  "dom m = dom m' \<Longrightarrow> m ++ m' = m'"
+  by (rule ext) (auto simp: map_add_def split: option.splits)
+
+lemma map_add_right_dom_eq:
+  "\<lbrakk> m\<^isub>0 ++ m\<^isub>1 = m\<^isub>0' ++ m\<^isub>1'; dom m\<^isub>1 = dom m\<^isub>1' \<rbrakk> \<Longrightarrow> m\<^isub>1 = m\<^isub>1'"
+  unfolding map_add_def
+  by (rule ext, rule ccontr,
+      drule_tac x=x in fun_cong, clarsimp split: option.splits,
+      drule sym, drule sym, force+)
+
+lemma map_le_same_dom_eq:
+  "\<lbrakk> m\<^isub>0 \<subseteq>\<^sub>m m\<^isub>1 ; dom m\<^isub>0 = dom m\<^isub>1 \<rbrakk> \<Longrightarrow> m\<^isub>0 = m\<^isub>1"
+  by (auto intro!: ext simp: map_le_def elim!: ballE)
+
+
+subsection {* Properties of map restriction *}
+
+lemma restrict_map_cancel:
+  "(m |` S = m |` T) = (dom m \<inter> S = dom m \<inter> T)"
+  by (fastforce intro: ext dest: fun_cong
+               simp: restrict_map_def None_not_eq
+               split: split_if_asm)
+
+lemma map_add_restricted_self [simp]:
+  "m ++ m |` S = m"
+  by (auto intro: ext simp: restrict_map_def map_add_def split: option.splits)
+
+lemma map_add_restrict_dom_right [simp]:
+  "(m ++ m') |` dom m' = m'"
+  by (rule ext, auto simp: restrict_map_def map_add_def split: option.splits)
+
+lemma restrict_map_UNIV [simp]:
+  "m |` UNIV = m"
+  by (simp add: restrict_map_def)
+
+lemma restrict_map_dom:
+  "S = dom m \<Longrightarrow> m |` S = m"
+  by (auto intro!: ext simp: restrict_map_def None_not_eq)
+
+lemma restrict_map_subdom:
+  "dom m \<subseteq> S \<Longrightarrow> m |` S = m"
+  by (fastforce simp: restrict_map_def None_com intro: ext)
+
+lemma map_add_restrict:
+  "(m\<^isub>0 ++ m\<^isub>1) |` S = ((m\<^isub>0 |` S) ++ (m\<^isub>1 |` S))"
+  by (force simp: map_add_def restrict_map_def intro: ext)
+
+lemma map_le_restrict:
+  "m \<subseteq>\<^sub>m m' \<Longrightarrow> m = m' |` dom m"
+  by (force simp: map_le_def restrict_map_def None_com intro: ext)
+
+lemma restrict_map_le:
+  "m |` S \<subseteq>\<^sub>m m"
+  by (auto simp: map_le_def)
+
+lemma restrict_map_remerge:
+  "\<lbrakk> S \<inter> T = {} \<rbrakk> \<Longrightarrow> m |` S ++ m |` T = m |` (S \<union> T)"
+  by (rule ext, clarsimp simp: restrict_map_def map_add_def
+                         split: option.splits)
+
+lemma restrict_map_empty:
+  "dom m \<inter> S = {} \<Longrightarrow> m |` S = empty"
+  by (fastforce simp: restrict_map_def intro: ext)
+
+lemma map_add_restrict_comp_right [simp]:
+  "(m |` S ++ m |` (UNIV - S)) = m"
+  by (force simp: map_add_def restrict_map_def split: option.splits intro: ext)
+
+lemma map_add_restrict_comp_right_dom [simp]:
+  "(m |` S ++ m |` (dom m - S)) = m"
+  by (auto simp: map_add_def restrict_map_def split: option.splits intro!: ext)
+
+lemma map_add_restrict_comp_left [simp]:
+  "(m |` (UNIV - S) ++ m |` S) = m"
+  by (subst map_add_comm, auto)
+
+lemma restrict_self_UNIV:
+  "m |` (dom m - S) = m |` (UNIV - S)"
+  by (auto intro!: ext simp: restrict_map_def)
+
+lemma map_add_restrict_nonmember_right:
+  "x \<notin> dom m' \<Longrightarrow> (m ++ m') |` {x} = m |` {x}"
+  by (rule ext, auto simp: restrict_map_def map_add_def split: option.splits)
+
+lemma map_add_restrict_nonmember_left:
+  "x \<notin> dom m \<Longrightarrow> (m ++ m') |` {x} = m' |` {x}"
+  by (rule ext, auto simp: restrict_map_def map_add_def split: option.splits)
+
+lemma map_add_restrict_right:
+  "x \<subseteq> dom m' \<Longrightarrow> (m ++ m') |` x = m' |` x"
+  by (rule ext, auto simp: restrict_map_def map_add_def split: option.splits)
+
+lemma restrict_map_compose:
+  "\<lbrakk> S \<union> T = dom m ; S \<inter> T = {} \<rbrakk> \<Longrightarrow> m |` S ++ m |` T = m"
+  by (fastforce intro: ext simp: map_add_def restrict_map_def)
+
+lemma map_le_dom_subset_restrict:
+  "\<lbrakk> m' \<subseteq>\<^sub>m m; dom m' \<subseteq> S \<rbrakk> \<Longrightarrow> m' \<subseteq>\<^sub>m (m |` S)"
+  by (force simp: restrict_map_def map_le_def)
+
+lemma map_le_dom_restrict_sub_add:
+  "m' \<subseteq>\<^sub>m m \<Longrightarrow> m |` (dom m - dom m') ++ m' = m"
+  by (auto simp: None_com map_add_def restrict_map_def map_le_def
+           split: option.splits
+           intro!: ext)
+     (force simp: Some_com)+
+
+lemma subset_map_restrict_sub_add:
+  "T \<subseteq> S \<Longrightarrow> m |` (S - T) ++ m |` T = m |` S"
+  by (auto simp: restrict_map_def map_add_def intro!: ext split: option.splits)
+
+lemma restrict_map_sub_union:
+  "m |` (dom m - (S \<union> T)) = (m |` (dom m - T)) |` (dom m - S)"
+  by (auto intro!: ext simp: restrict_map_def)
+
+lemma prod_restrict_map_add:
+  "\<lbrakk> S \<union> T = U; S \<inter> T = {} \<rbrakk> \<Longrightarrow> m |` (X \<times> S) ++ m |` (X \<times> T) = m |` (X \<times> U)"
+  by (auto simp: map_add_def restrict_map_def intro!: ext split: option.splits)
+
+
+section {* Things that should not go into Map.thy (separation logic) *}
+
+subsection {* Definitions *}
+
+text {* Map disjuction *}
+
+definition
+  map_disj :: "('a \<rightharpoonup> 'b) \<Rightarrow> ('a \<rightharpoonup> 'b) \<Rightarrow> bool" (infix "\<bottom>" 51) where
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<equiv> dom h\<^isub>0 \<inter> dom h\<^isub>1 = {}"
+
+declare None_not_eq [simp]
+
+
+subsection {* Properties of @{term "sub_restrict_map"} *}
+
+lemma restrict_map_sub_disj: "h |` S \<bottom> h `- S"
+  by (fastforce simp: sub_restrict_map_def restrict_map_def map_disj_def
+               split: option.splits split_if_asm)
+
+lemma restrict_map_sub_add: "h |` S ++ h `- S = h"
+  by (fastforce simp: sub_restrict_map_def restrict_map_def map_add_def
+               split: option.splits split_if
+               intro: ext)
+
+
+subsection {* Properties of map disjunction *}
+
+lemma map_disj_empty_right [simp]:
+  "h \<bottom> empty"
+  by (simp add: map_disj_def)
+
+lemma map_disj_empty_left [simp]:
+  "empty \<bottom> h"
+  by (simp add: map_disj_def)
+
+lemma map_disj_com:
+  "h\<^isub>0 \<bottom> h\<^isub>1 = h\<^isub>1 \<bottom> h\<^isub>0"
+  by (simp add: map_disj_def, fast)
+
+lemma map_disjD:
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> dom h\<^isub>0 \<inter> dom h\<^isub>1 = {}"
+  by (simp add: map_disj_def)
+
+lemma map_disjI:
+  "dom h\<^isub>0 \<inter> dom h\<^isub>1 = {} \<Longrightarrow> h\<^isub>0 \<bottom> h\<^isub>1"
+  by (simp add: map_disj_def)
+
+
+subsection {* Map associativity-commutativity based on map disjuction *}
+
+lemma map_add_com:
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> h\<^isub>0 ++ h\<^isub>1 = h\<^isub>1 ++ h\<^isub>0"
+  by (drule map_disjD, rule map_add_comm, force)
+
+lemma map_add_left_commute:
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> h\<^isub>0 ++ (h\<^isub>1 ++ h\<^isub>2) = h\<^isub>1 ++ (h\<^isub>0 ++ h\<^isub>2)"
+  by (simp add: map_add_com map_disj_com map_add_assoc)
+
+lemma map_add_disj:
+  "h\<^isub>0 \<bottom> (h\<^isub>1 ++ h\<^isub>2) = (h\<^isub>0 \<bottom> h\<^isub>1 \<and> h\<^isub>0 \<bottom> h\<^isub>2)"
+  by (simp add: map_disj_def, fast)
+
+lemma map_add_disj':
+  "(h\<^isub>1 ++ h\<^isub>2) \<bottom> h\<^isub>0 = (h\<^isub>1 \<bottom> h\<^isub>0 \<and> h\<^isub>2 \<bottom> h\<^isub>0)"
+  by (simp add: map_disj_def, fast)
+
+text {*
+  We redefine @{term "map_add"} associativity to bind to the right, which
+  seems to be the more common case.
+  Note that when a theory includes Map again, @{text "map_add_assoc"} will
+  return to the simpset and will cause infinite loops if its symmetric
+  counterpart is added (e.g. via @{text "map_add_ac"})
+  *}
+
+declare map_add_assoc [simp del]
+
+text {*
+  Since the associativity-commutativity of @{term "map_add"} relies on
+  map disjunction, we include some basic rules into the ac set.
+  *}
+
+lemmas map_add_ac =
+  map_add_assoc[symmetric] map_add_com map_disj_com
+  map_add_left_commute map_add_disj map_add_disj'
+
+
+subsection {* Basic properties *}
+
+lemma map_disj_None_right:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; x \<in> dom h\<^isub>0 \<rbrakk> \<Longrightarrow> h\<^isub>1 x = None"
+  by (auto simp: map_disj_def dom_def)
+
+lemma map_disj_None_left:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; x \<in> dom h\<^isub>1 \<rbrakk> \<Longrightarrow> h\<^isub>0 x = None"
+  by (auto simp: map_disj_def dom_def)
+
+lemma map_disj_None_left':
+  "\<lbrakk> h\<^isub>0 x = Some y ; h\<^isub>1 \<bottom> h\<^isub>0 \<rbrakk> \<Longrightarrow> h\<^isub>1 x = None "
+  by (auto simp: map_disj_def)
+
+lemma map_disj_None_right':
+  "\<lbrakk> h\<^isub>1 x = Some y ; h\<^isub>1 \<bottom> h\<^isub>0 \<rbrakk> \<Longrightarrow> h\<^isub>0 x = None "
+  by (auto simp: map_disj_def)
+
+lemma map_disj_common:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; h\<^isub>0 p = Some v ; h\<^isub>1 p = Some v' \<rbrakk> \<Longrightarrow> False"
+  by (frule (1) map_disj_None_left', simp)
+
+lemma map_disj_eq_dom_left:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; dom h\<^isub>0' = dom h\<^isub>0 \<rbrakk> \<Longrightarrow> h\<^isub>0' \<bottom> h\<^isub>1"
+  by (auto simp: map_disj_def)
+
+
+subsection {* Map disjunction and addition *}
+
+lemma map_add_eval_left:
+  "\<lbrakk> x \<in> dom h ; h \<bottom> h' \<rbrakk> \<Longrightarrow> (h ++ h') x = h x"
+  by (auto dest!: map_disj_None_right simp: map_add_def cong: option.case_cong)
+
+lemma map_add_eval_right:
+  "\<lbrakk> x \<in> dom h' ; h \<bottom> h' \<rbrakk> \<Longrightarrow> (h ++ h') x = h' x"
+  by (auto elim!: map_disjD simp: map_add_comm map_add_eval_left map_disj_com)
+
+lemma map_add_eval_left':
+  "\<lbrakk> x \<notin> dom h' ; h \<bottom> h' \<rbrakk> \<Longrightarrow> (h ++ h') x = h x"
+  by (clarsimp simp: map_disj_def map_add_def split: option.splits)
+
+lemma map_add_eval_right':
+  "\<lbrakk> x \<notin> dom h ; h \<bottom> h' \<rbrakk> \<Longrightarrow> (h ++ h') x = h' x"
+  by (clarsimp simp: map_disj_def map_add_def split: option.splits)
+
+lemma map_add_left_dom_eq:
+  assumes eq: "h\<^isub>0 ++ h\<^isub>1 = h\<^isub>0' ++ h\<^isub>1'"
+  assumes etc: "h\<^isub>0 \<bottom> h\<^isub>1" "h\<^isub>0' \<bottom> h\<^isub>1'" "dom h\<^isub>0 = dom h\<^isub>0'"
+  shows "h\<^isub>0 = h\<^isub>0'"
+proof -
+  from eq have "h\<^isub>1 ++ h\<^isub>0 = h\<^isub>1' ++ h\<^isub>0'" using etc by (simp add: map_add_ac)
+  thus ?thesis using etc
+    by (fastforce elim!: map_add_right_dom_eq simp: map_add_ac)
+qed
+
+lemma map_add_left_eq:
+  assumes eq: "h\<^isub>0 ++ h = h\<^isub>1 ++ h"
+  assumes disj: "h\<^isub>0 \<bottom> h" "h\<^isub>1 \<bottom> h"
+  shows "h\<^isub>0 = h\<^isub>1"
+proof (rule ext)
+  fix x
+  from eq have eq': "(h\<^isub>0 ++ h) x = (h\<^isub>1 ++ h) x" by (auto intro!: ext)
+  { assume "x \<in> dom h"
+    hence "h\<^isub>0 x = h\<^isub>1 x" using disj by (simp add: map_disj_None_left)
+  } moreover {
+    assume "x \<notin> dom h"
+    hence "h\<^isub>0 x = h\<^isub>1 x" using disj eq' by (simp add: map_add_eval_left')
+  }
+  ultimately show "h\<^isub>0 x = h\<^isub>1 x" by cases
+qed
+
+lemma map_add_right_eq:
+  "\<lbrakk>h ++ h\<^isub>0 = h ++ h\<^isub>1; h\<^isub>0 \<bottom> h; h\<^isub>1 \<bottom> h\<rbrakk> \<Longrightarrow> h\<^isub>0 = h\<^isub>1"
+  by (rule_tac h=h in map_add_left_eq, auto simp: map_add_ac)
+
+lemma map_disj_add_eq_dom_right_eq:
+  assumes merge: "h\<^isub>0 ++ h\<^isub>1 = h\<^isub>0' ++ h\<^isub>1'" and d: "dom h\<^isub>0 = dom h\<^isub>0'" and
+      ab_disj: "h\<^isub>0 \<bottom> h\<^isub>1" and cd_disj: "h\<^isub>0' \<bottom> h\<^isub>1'"
+  shows "h\<^isub>1 = h\<^isub>1'"
+proof (rule ext)
+  fix x
+  from merge have merge_x: "(h\<^isub>0 ++ h\<^isub>1) x = (h\<^isub>0' ++ h\<^isub>1') x" by simp
+  with d ab_disj cd_disj show  "h\<^isub>1 x = h\<^isub>1' x"
+    by - (case_tac "h\<^isub>1 x", case_tac "h\<^isub>1' x", simp, fastforce simp: map_disj_def,
+          case_tac "h\<^isub>1' x", clarsimp, simp add: Some_com,
+          force simp: map_disj_def, simp)
+qed
+
+lemma map_disj_add_eq_dom_left_eq:
+  assumes add: "h\<^isub>0 ++ h\<^isub>1 = h\<^isub>0' ++ h\<^isub>1'" and
+          dom: "dom h\<^isub>1 = dom h\<^isub>1'" and
+          disj: "h\<^isub>0 \<bottom> h\<^isub>1" "h\<^isub>0' \<bottom> h\<^isub>1'"
+  shows "h\<^isub>0 = h\<^isub>0'"
+proof -
+  have "h\<^isub>1 ++ h\<^isub>0 = h\<^isub>1' ++ h\<^isub>0'" using add disj by (simp add: map_add_ac)
+  thus ?thesis using dom disj
+    by - (rule map_disj_add_eq_dom_right_eq, auto simp: map_disj_com)
+qed
+
+lemma map_add_left_cancel:
+  assumes disj: "h\<^isub>0 \<bottom> h\<^isub>1" "h\<^isub>0 \<bottom> h\<^isub>1'"
+  shows "(h\<^isub>0 ++ h\<^isub>1 = h\<^isub>0 ++ h\<^isub>1') = (h\<^isub>1 = h\<^isub>1')"
+proof (rule iffI, rule ext)
+  fix x
+  assume "(h\<^isub>0 ++ h\<^isub>1) = (h\<^isub>0 ++ h\<^isub>1')"
+  hence "(h\<^isub>0 ++ h\<^isub>1) x = (h\<^isub>0 ++ h\<^isub>1') x" by (auto intro!: ext)
+  hence "h\<^isub>1 x = h\<^isub>1' x" using disj
+    by - (cases "x \<in> dom h\<^isub>0",
+          simp_all add: map_disj_None_right map_add_eval_right')
+  thus "h\<^isub>1 x = h\<^isub>1' x" by (auto intro!: ext)
+qed auto
+
+lemma map_add_lr_disj:
+  "\<lbrakk> h\<^isub>0 ++ h\<^isub>1 = h\<^isub>0' ++ h\<^isub>1'; h\<^isub>1 \<bottom> h\<^isub>1'  \<rbrakk> \<Longrightarrow> dom h\<^isub>1 \<subseteq> dom h\<^isub>0'"
+  by (clarsimp simp: map_disj_def map_add_def, drule_tac x=x in fun_cong)
+     (auto split: option.splits)
+
+
+subsection {* Map disjunction and map updates *}
+
+lemma map_disj_update_left [simp]:
+  "p \<in> dom h\<^isub>1 \<Longrightarrow> h\<^isub>0 \<bottom> h\<^isub>1(p \<mapsto> v) = h\<^isub>0 \<bottom> h\<^isub>1"
+  by (clarsimp simp add: map_disj_def, blast)
+
+lemma map_disj_update_right [simp]:
+  "p \<in> dom h\<^isub>1 \<Longrightarrow> h\<^isub>1(p \<mapsto> v) \<bottom> h\<^isub>0 = h\<^isub>1 \<bottom> h\<^isub>0"
+  by (simp add: map_disj_com)
+
+lemma map_add_update_left:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; p \<in> dom h\<^isub>0 \<rbrakk> \<Longrightarrow> (h\<^isub>0 ++ h\<^isub>1)(p \<mapsto> v) = (h\<^isub>0(p \<mapsto> v) ++ h\<^isub>1)"
+  by (drule (1) map_disj_None_right)
+     (auto intro: ext simp: map_add_def cong: option.case_cong)
+
+lemma map_add_update_right:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; p \<in> dom h\<^isub>1  \<rbrakk> \<Longrightarrow> (h\<^isub>0 ++ h\<^isub>1)(p \<mapsto> v) = (h\<^isub>0 ++ h\<^isub>1 (p \<mapsto> v))"
+  by (drule (1) map_disj_None_left)
+     (auto intro: ext simp: map_add_def cong: option.case_cong)
+
+lemma map_add3_update:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; h\<^isub>1  \<bottom> h\<^isub>2 ; h\<^isub>0 \<bottom> h\<^isub>2 ; p \<in> dom h\<^isub>0 \<rbrakk>
+  \<Longrightarrow> (h\<^isub>0 ++ h\<^isub>1 ++ h\<^isub>2)(p \<mapsto> v) = h\<^isub>0(p \<mapsto> v) ++ h\<^isub>1 ++ h\<^isub>2"
+  by (auto simp: map_add_update_left[symmetric] map_add_ac)
+
+
+subsection {* Map disjunction and @{term "map_le"} *}
+
+lemma map_le_override [simp]:
+  "\<lbrakk> h \<bottom> h' \<rbrakk> \<Longrightarrow> h \<subseteq>\<^sub>m h ++ h'"
+  by (auto simp: map_le_def map_add_def map_disj_def split: option.splits)
+
+lemma map_leI_left:
+  "\<lbrakk> h = h\<^isub>0 ++ h\<^isub>1 ; h\<^isub>0 \<bottom> h\<^isub>1 \<rbrakk> \<Longrightarrow> h\<^isub>0 \<subseteq>\<^sub>m h" by auto
+
+lemma map_leI_right:
+  "\<lbrakk> h = h\<^isub>0 ++ h\<^isub>1 ; h\<^isub>0 \<bottom> h\<^isub>1 \<rbrakk> \<Longrightarrow> h\<^isub>1 \<subseteq>\<^sub>m h" by auto
+
+lemma map_disj_map_le:
+  "\<lbrakk> h\<^isub>0' \<subseteq>\<^sub>m h\<^isub>0; h\<^isub>0 \<bottom> h\<^isub>1 \<rbrakk> \<Longrightarrow> h\<^isub>0' \<bottom> h\<^isub>1"
+  by (force simp: map_disj_def map_le_def)
+
+lemma map_le_on_disj_left:
+  "\<lbrakk> h' \<subseteq>\<^sub>m h ; h\<^isub>0 \<bottom> h\<^isub>1 ; h' = h\<^isub>0 ++ h\<^isub>1 \<rbrakk> \<Longrightarrow> h\<^isub>0 \<subseteq>\<^sub>m h"
+  unfolding map_le_def
+  by (rule ballI, erule_tac x=a in ballE, auto simp: map_add_eval_left)+
+
+lemma map_le_on_disj_right:
+  "\<lbrakk> h' \<subseteq>\<^sub>m h ; h\<^isub>0 \<bottom> h\<^isub>1 ; h' = h\<^isub>1 ++ h\<^isub>0 \<rbrakk> \<Longrightarrow> h\<^isub>0 \<subseteq>\<^sub>m h"
+  by (auto simp: map_le_on_disj_left map_add_ac)
+
+lemma map_le_add_cancel:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1 ; h\<^isub>0' \<subseteq>\<^sub>m h\<^isub>0 \<rbrakk> \<Longrightarrow> h\<^isub>0' ++ h\<^isub>1 \<subseteq>\<^sub>m h\<^isub>0 ++ h\<^isub>1"
+  by (auto simp: map_le_def map_add_def map_disj_def split: option.splits)
+
+lemma map_le_override_bothD:
+  assumes subm: "h\<^isub>0' ++ h\<^isub>1 \<subseteq>\<^sub>m h\<^isub>0 ++ h\<^isub>1"
+  assumes disj': "h\<^isub>0' \<bottom> h\<^isub>1"
+  assumes disj: "h\<^isub>0 \<bottom> h\<^isub>1"
+  shows "h\<^isub>0' \<subseteq>\<^sub>m h\<^isub>0"
+unfolding map_le_def
+proof (rule ballI)
+  fix a
+  assume a: "a \<in> dom h\<^isub>0'"
+  hence sumeq: "(h\<^isub>0' ++ h\<^isub>1) a = (h\<^isub>0 ++ h\<^isub>1) a"
+    using subm unfolding map_le_def by auto
+  from a have "a \<notin> dom h\<^isub>1" using disj' by (auto dest!: map_disj_None_right)
+  thus "h\<^isub>0' a = h\<^isub>0 a" using a sumeq disj disj'
+    by (simp add: map_add_eval_left map_add_eval_left')
+qed
+
+lemma map_le_conv:
+  "(h\<^isub>0' \<subseteq>\<^sub>m h\<^isub>0 \<and> h\<^isub>0' \<noteq> h\<^isub>0) = (\<exists>h\<^isub>1. h\<^isub>0 = h\<^isub>0' ++ h\<^isub>1 \<and> h\<^isub>0' \<bottom> h\<^isub>1 \<and> h\<^isub>0' \<noteq> h\<^isub>0)"
+  unfolding map_le_def map_disj_def map_add_def
+  by (rule iffI,
+      clarsimp intro!: exI[where x="\<lambda>x. if x \<notin> dom h\<^isub>0' then h\<^isub>0 x else None"])
+     (fastforce intro: ext intro: split: option.splits split_if_asm)+
+
+lemma map_le_conv2:
+  "h\<^isub>0' \<subseteq>\<^sub>m h\<^isub>0 = (\<exists>h\<^isub>1. h\<^isub>0 = h\<^isub>0' ++ h\<^isub>1 \<and> h\<^isub>0' \<bottom> h\<^isub>1)"
+  by (case_tac "h\<^isub>0'=h\<^isub>0", insert map_le_conv, auto intro: exI[where x=empty])
+
+
+subsection {* Map disjunction and restriction *}
+
+lemma map_disj_comp [simp]:
+  "h\<^isub>0 \<bottom> h\<^isub>1 |` (UNIV - dom h\<^isub>0)"
+  by (force simp: map_disj_def)
+
+lemma restrict_map_disj:
+  "S \<inter> T = {} \<Longrightarrow> h |` S \<bottom> h |` T"
+  by (auto simp: map_disj_def restrict_map_def dom_def)
+
+lemma map_disj_restrict_dom [simp]:
+  "h\<^isub>0 \<bottom> h\<^isub>1 |` (dom h\<^isub>1 - dom h\<^isub>0)"
+  by (force simp: map_disj_def)
+
+lemma restrict_map_disj_dom_empty:
+  "h \<bottom> h' \<Longrightarrow> h |` dom h' = empty"
+  by (fastforce simp: map_disj_def restrict_map_def intro: ext)
+
+lemma restrict_map_univ_disj_eq:
+  "h \<bottom> h' \<Longrightarrow> h |` (UNIV - dom h') = h"
+  by (rule ext, auto simp: map_disj_def restrict_map_def)
+
+lemma restrict_map_disj_dom:
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> h |` dom h\<^isub>0 \<bottom> h |` dom h\<^isub>1"
+  by (auto simp: map_disj_def restrict_map_def dom_def)
+
+lemma map_add_restrict_dom_left:
+  "h \<bottom> h' \<Longrightarrow> (h ++ h') |` dom h = h"
+  by (rule ext, auto simp: restrict_map_def map_add_def dom_def map_disj_def
+                     split: option.splits)
+
+lemma map_add_restrict_dom_left':
+  "h \<bottom> h' \<Longrightarrow> S = dom h \<Longrightarrow> (h ++ h') |` S = h"
+  by (rule ext, auto simp: restrict_map_def map_add_def dom_def map_disj_def
+                     split: option.splits)
+
+lemma restrict_map_disj_left:
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> h\<^isub>0 |` S \<bottom> h\<^isub>1"
+  by (auto simp: map_disj_def)
+
+lemma restrict_map_disj_right:
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> h\<^isub>0 \<bottom> h\<^isub>1 |` S"
+  by (auto simp: map_disj_def)
+
+lemmas restrict_map_disj_both = restrict_map_disj_right restrict_map_disj_left
+
+lemma map_dom_disj_restrict_right:
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> (h\<^isub>0 ++ h\<^isub>0') |` dom h\<^isub>1 = h\<^isub>0' |` dom h\<^isub>1"
+  by (simp add: map_add_restrict restrict_map_empty map_disj_def)
+
+lemma restrict_map_on_disj:
+  "h\<^isub>0' \<bottom> h\<^isub>1 \<Longrightarrow> h\<^isub>0 |` dom h\<^isub>0' \<bottom> h\<^isub>1"
+  unfolding map_disj_def by auto
+
+lemma restrict_map_on_disj':
+  "h\<^isub>0 \<bottom> h\<^isub>1 \<Longrightarrow> h\<^isub>0 \<bottom> h\<^isub>1 |` S"
+  by (auto simp: map_disj_def map_add_def)
+
+lemma map_le_sub_dom:
+  "\<lbrakk> h\<^isub>0 ++ h\<^isub>1 \<subseteq>\<^sub>m h ; h\<^isub>0 \<bottom> h\<^isub>1 \<rbrakk> \<Longrightarrow> h\<^isub>0 \<subseteq>\<^sub>m h |` (dom h - dom h\<^isub>1)"
+  by (rule map_le_override_bothD, subst map_le_dom_restrict_sub_add)
+     (auto elim: map_add_le_mapE simp: map_add_ac)
+
+lemma map_submap_break:
+  "\<lbrakk> h \<subseteq>\<^sub>m h' \<rbrakk> \<Longrightarrow> h' = (h' |` (UNIV - dom h)) ++ h"
+  by (fastforce intro!: ext split: option.splits
+               simp: map_le_restrict restrict_map_def map_le_def map_add_def
+                     dom_def)
+
+lemma map_add_disj_restrict_both:
+  "\<lbrakk> h\<^isub>0 \<bottom> h\<^isub>1; S \<inter> S' = {}; T \<inter> T' = {} \<rbrakk>
+   \<Longrightarrow> (h\<^isub>0 |` S) ++ (h\<^isub>1 |` T) \<bottom> (h\<^isub>0 |` S') ++ (h\<^isub>1 |` T')"
+  by (auto simp: map_add_ac intro!: restrict_map_disj_both restrict_map_disj)
+
+end