lh-l4v/lib/sep_algebra/Separation_Algebra.thy

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(*
* Copyright 2014, NICTA
*
* This software may be distributed and modified according to the terms of
* the BSD 2-Clause license. Note that NO WARRANTY is provided.
* See "LICENSE_BSD2.txt" for details.
*
* @TAG(NICTA_BSD)
*)
(* Authors: Gerwin Klein and Rafal Kolanski, 2012
Maintainers: Gerwin Klein <kleing at cse.unsw.edu.au>
Rafal Kolanski <rafal.kolanski at nicta.com.au>
*)
header "Abstract Separation Algebra"
theory Separation_Algebra
imports
Main
"~~/src/Tools/Adhoc_Overloading"
Arbitrary_Comm_Monoid
begin
text {* This theory is the main abstract separation algebra development *}
section {* Input syntax for lifting boolean predicates to separation predicates *}
abbreviation (input)
pred_and :: "('a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool" (infixr "and" 35) where
"a and b \<equiv> \<lambda>s. a s \<and> b s"
abbreviation (input)
pred_or :: "('a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool" (infixr "or" 30) where
"a or b \<equiv> \<lambda>s. a s \<or> b s"
abbreviation (input)
pred_not :: "('a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool" ("not _" [40] 40) where
"not a \<equiv> \<lambda>s. \<not>a s"
abbreviation (input)
pred_imp :: "('a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool" (infixr "imp" 25) where
"a imp b \<equiv> \<lambda>s. a s \<longrightarrow> b s"
abbreviation (input)
pred_K :: "'b \<Rightarrow> 'a \<Rightarrow> 'b" ("\<langle>_\<rangle>") where
"\<langle>f\<rangle> \<equiv> \<lambda>s. f"
abbreviation (input)
pred_ex :: "('b \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool" (binder "EXS " 10) where
"EXS x. P x \<equiv> \<lambda>s. \<exists>x. P x s"
abbreviation (input)
pred_all :: "('b \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> bool" (binder "ALLS " 10) where
"ALLS x. P x \<equiv> \<lambda>s. \<forall>x. P x s"
section {* Associative/Commutative Monoid Basis of Separation Algebras *}
class pre_sep_algebra = zero + plus +
fixes sep_disj :: "'a => 'a => bool" (infix "##" 60)
assumes sep_disj_zero [simp]: "x ## 0"
assumes sep_disj_commuteI: "x ## y \<Longrightarrow> y ## x"
assumes sep_add_zero [simp]: "x + 0 = x"
assumes sep_add_commute: "x ## y \<Longrightarrow> x + y = y + x"
assumes sep_add_assoc:
"\<lbrakk> x ## y; y ## z; x ## z \<rbrakk> \<Longrightarrow> (x + y) + z = x + (y + z)"
begin
lemma sep_disj_commute: "x ## y = y ## x"
by (blast intro: sep_disj_commuteI)
lemma sep_add_left_commute:
assumes a: "a ## b" "b ## c" "a ## c"
shows "b + (a + c) = a + (b + c)" (is "?lhs = ?rhs")
proof -
have "?lhs = b + a + c" using a
by (simp add: sep_add_assoc[symmetric] sep_disj_commute)
also have "... = a + b + c" using a
by (simp add: sep_add_commute sep_disj_commute)
also have "... = ?rhs" using a
by (simp add: sep_add_assoc sep_disj_commute)
finally show ?thesis .
qed
lemmas sep_add_ac = sep_add_assoc sep_add_commute sep_add_left_commute
sep_disj_commute (* nearly always necessary *)
end
section {* Separation Algebra as Defined by Calcagno et al. *}
class sep_algebra = pre_sep_algebra +
assumes sep_disj_addD1: "\<lbrakk> x ## y + z; y ## z \<rbrakk> \<Longrightarrow> x ## y"
assumes sep_disj_addI1: "\<lbrakk> x ## y + z; y ## z \<rbrakk> \<Longrightarrow> x + y ## z"
begin
subsection {* Basic Construct Definitions and Abbreviations *}
(* Lower precedence than pred_conj, otherwise "P \<and>* Q and R" is ambiguous,
* (noting that Isabelle turns "(P \<and>* Q) and R" into "P \<and>* Q and R").
*)
definition
sep_conj :: "('a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> bool)" (infixr "**" 36)
where
"P ** Q \<equiv> \<lambda>h. \<exists>x y. x ## y \<and> h = x + y \<and> P x \<and> Q y"
notation
sep_conj (infixr "\<and>*" 36)
notation (latex output)
sep_conj (infixr "\<and>\<^sup>*" 36)
definition
sep_empty :: "'a \<Rightarrow> bool" ("\<box>") where
"\<box> \<equiv> \<lambda>h. h = 0"
definition
sep_impl :: "('a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> bool) \<Rightarrow> ('a \<Rightarrow> bool)" (infixr "\<longrightarrow>*" 25)
where
"P \<longrightarrow>* Q \<equiv> \<lambda>h. \<forall>h'. h ## h' \<and> P h' \<longrightarrow> Q (h + h')"
definition
sep_substate :: "'a \<Rightarrow> 'a \<Rightarrow> bool" (infix "\<preceq>" 60) where
"x \<preceq> y \<equiv> \<exists>z. x ## z \<and> x + z = y"
(* We want these to be abbreviations not definitions, because basic True and
False will occur by simplification in sep_conj terms *)
abbreviation
"sep_true \<equiv> \<langle>True\<rangle>"
abbreviation
"sep_false \<equiv> \<langle>False\<rangle>"
subsection {* Disjunction/Addition Properties *}
lemma disjoint_zero_sym [simp]: "0 ## x"
by (simp add: sep_disj_commute)
lemma sep_add_zero_sym [simp]: "0 + x = x"
by (simp add: sep_add_commute)
lemma sep_disj_addD2: "\<lbrakk> x ## y + z; y ## z \<rbrakk> \<Longrightarrow> x ## z"
by (metis sep_disj_addD1 sep_add_ac)
lemma sep_disj_addD: "\<lbrakk> x ## y + z; y ## z \<rbrakk> \<Longrightarrow> x ## y \<and> x ## z"
by (metis sep_disj_addD1 sep_disj_addD2)
lemma sep_add_disjD: "\<lbrakk> x + y ## z; x ## y \<rbrakk> \<Longrightarrow> x ## z \<and> y ## z"
by (metis sep_disj_addD sep_disj_commuteI)
lemma sep_disj_addI2:
"\<lbrakk> x ## y + z; y ## z \<rbrakk> \<Longrightarrow> x + z ## y"
by (metis sep_add_ac sep_disj_addI1)
lemma sep_add_disjI1:
"\<lbrakk> x + y ## z; x ## y \<rbrakk> \<Longrightarrow> x + z ## y"
by (metis sep_add_ac sep_add_disjD sep_disj_addI2)
lemma sep_add_disjI2:
"\<lbrakk> x + y ## z; x ## y \<rbrakk> \<Longrightarrow> z + y ## x"
by (metis sep_add_ac sep_add_disjD sep_disj_addI2)
lemma sep_disj_addI3:
"x + y ## z \<Longrightarrow> x ## y \<Longrightarrow> x ## y + z"
by (metis sep_add_ac sep_add_disjD sep_add_disjI2)
lemma sep_disj_add:
"\<lbrakk> y ## z; x ## y \<rbrakk> \<Longrightarrow> x ## y + z = x + y ## z"
by (metis sep_disj_addI1 sep_disj_addI3)
subsection {* Substate Properties *}
lemma sep_substate_disj_add:
"x ## y \<Longrightarrow> x \<preceq> x + y"
unfolding sep_substate_def by blast
lemma sep_substate_disj_add':
"x ## y \<Longrightarrow> x \<preceq> y + x"
by (simp add: sep_add_ac sep_substate_disj_add)
subsection {* Separating Conjunction Properties *}
lemma sep_conjD:
"(P \<and>* Q) h \<Longrightarrow> \<exists>x y. x ## y \<and> h = x + y \<and> P x \<and> Q y"
by (simp add: sep_conj_def)
lemma sep_conjE:
"\<lbrakk> (P ** Q) h; \<And>x y. \<lbrakk> P x; Q y; x ## y; h = x + y \<rbrakk> \<Longrightarrow> X \<rbrakk> \<Longrightarrow> X"
by (auto simp: sep_conj_def)
lemma sep_conjI:
"\<lbrakk> P x; Q y; x ## y; h = x + y \<rbrakk> \<Longrightarrow> (P ** Q) h"
by (auto simp: sep_conj_def)
lemma sep_conj_commuteI:
"(P ** Q) h \<Longrightarrow> (Q ** P) h"
by (auto intro!: sep_conjI elim!: sep_conjE simp: sep_add_ac)
lemma sep_conj_commute:
"(P ** Q) = (Q ** P)"
by (rule ext) (auto intro: sep_conj_commuteI)
lemma sep_conj_assoc:
"((P ** Q) ** R) = (P ** Q ** R)" (is "?lhs = ?rhs")
proof (rule ext, rule iffI)
fix h
assume a: "?lhs h"
then obtain x y z where "P x" and "Q y" and "R z"
and "x ## y" and "x ## z" and "y ## z" and "x + y ## z"
and "h = x + y + z"
by (auto dest!: sep_conjD dest: sep_add_disjD)
moreover
then have "x ## y + z"
by (simp add: sep_disj_add)
ultimately
show "?rhs h"
by (auto simp: sep_add_ac intro!: sep_conjI)
next
fix h
assume a: "?rhs h"
then obtain x y z where "P x" and "Q y" and "R z"
and "x ## y" and "x ## z" and "y ## z" and "x ## y + z"
and "h = x + y + z"
by (fastforce elim!: sep_conjE simp: sep_add_ac dest: sep_disj_addD)
thus "?lhs h"
by (metis sep_conj_def sep_disj_addI1)
qed
lemma sep_conj_impl:
"\<lbrakk> (P ** Q) h; \<And>h. P h \<Longrightarrow> P' h; \<And>h. Q h \<Longrightarrow> Q' h \<rbrakk> \<Longrightarrow> (P' ** Q') h"
by (erule sep_conjE, auto intro!: sep_conjI)
lemma sep_conj_impl1:
assumes P: "\<And>h. P h \<Longrightarrow> I h"
shows "(P ** R) h \<Longrightarrow> (I ** R) h"
by (auto intro: sep_conj_impl P)
lemma sep_globalise:
"\<lbrakk> (P ** R) h; (\<And>h. P h \<Longrightarrow> Q h) \<rbrakk> \<Longrightarrow> (Q ** R) h"
by (fast elim: sep_conj_impl)
lemma sep_conj_trivial_strip1:
"Q = R \<Longrightarrow> (P ** Q) = (P ** R)" by simp
lemma sep_conj_trivial_strip2:
"Q = R \<Longrightarrow> (Q ** P) = (R ** P)" by simp
lemma disjoint_subheaps_exist:
"\<exists>x y. x ## y \<and> h = x + y"
by (rule_tac x=0 in exI, auto)
lemma sep_conj_left_commute: (* for permutative rewriting *)
"(P ** (Q ** R)) = (Q ** (P ** R))" (is "?x = ?y")
proof -
have "?x = ((Q ** R) ** P)" by (simp add: sep_conj_commute)
also have "\<dots> = (Q ** (R ** P))" by (subst sep_conj_assoc, simp)
finally show ?thesis by (simp add: sep_conj_commute)
qed
lemmas sep_conj_ac = sep_conj_commute sep_conj_assoc sep_conj_left_commute
lemma sep_empty_zero [simp,intro!]: "\<box> 0"
by (simp add: sep_empty_def)
subsection {* Properties of @{text sep_true} and @{text sep_false} *}
lemma sep_conj_sep_true:
"P h \<Longrightarrow> (P ** sep_true) h"
by (simp add: sep_conjI[where y=0])
lemma sep_conj_sep_true':
"P h \<Longrightarrow> (sep_true ** P) h"
by (simp add: sep_conjI[where x=0])
lemma sep_conj_true [simp]:
"(sep_true ** sep_true) = sep_true"
unfolding sep_conj_def
by (auto intro!: ext intro: disjoint_subheaps_exist)
lemma sep_conj_false_right [simp]:
"(P ** sep_false) = sep_false"
by (force elim: sep_conjE intro!: ext)
lemma sep_conj_false_left [simp]:
"(sep_false ** P) = sep_false"
by (subst sep_conj_commute) (rule sep_conj_false_right)
subsection {* Properties of @{const sep_empty} *}
lemma sep_conj_empty [simp]:
"(P ** \<box>) = P"
by (simp add: sep_conj_def sep_empty_def)
lemma sep_conj_empty'[simp]:
"(\<box> ** P) = P"
by (subst sep_conj_commute, rule sep_conj_empty)
lemma sep_conj_sep_emptyI:
"P h \<Longrightarrow> (P ** \<box>) h"
by simp
lemma sep_conj_sep_emptyE:
"\<lbrakk> P s; (P ** \<box>) s \<Longrightarrow> (Q ** R) s \<rbrakk> \<Longrightarrow> (Q ** R) s"
by simp
subsection {* Properties of top (@{text sep_true}) *}
lemma sep_conj_true_P [simp]:
"(sep_true ** (sep_true ** P)) = (sep_true ** P)"
by (simp add: sep_conj_assoc[symmetric])
lemma sep_conj_disj:
"((P or Q) ** R) = ((P ** R) or (Q ** R))"
by (auto simp: sep_conj_def intro!: ext)
lemma sep_conj_sep_true_left:
"(P ** Q) h \<Longrightarrow> (sep_true ** Q) h"
by (erule sep_conj_impl, simp+)
lemma sep_conj_sep_true_right:
"(P ** Q) h \<Longrightarrow> (P ** sep_true) h"
by (subst (asm) sep_conj_commute, drule sep_conj_sep_true_left,
simp add: sep_conj_ac)
subsection {* Separating Conjunction with Quantifiers *}
lemma sep_conj_conj:
"((P and Q) ** R) h \<Longrightarrow> ((P ** R) and (Q ** R)) h"
by (force intro: sep_conjI elim!: sep_conjE)
lemma sep_conj_exists1:
"((EXS x. P x) ** Q) = (EXS x. (P x ** Q))"
by (force intro!: ext intro: sep_conjI elim: sep_conjE)
lemma sep_conj_exists2:
"(P ** (EXS x. Q x)) = (EXS x. P ** Q x)"
by (force intro!: sep_conjI ext elim!: sep_conjE)
lemmas sep_conj_exists = sep_conj_exists1 sep_conj_exists2
lemma sep_conj_spec1:
"((ALLS x. P x) ** Q) h \<Longrightarrow> (P x ** Q) h"
by (force intro: sep_conjI elim: sep_conjE)
lemma sep_conj_spec2:
"(P ** (ALLS x. Q x)) h \<Longrightarrow> (P ** Q x) h"
by (force intro: sep_conjI elim: sep_conjE)
lemmas sep_conj_spec = sep_conj_spec1 sep_conj_spec2
subsection {* Properties of Separating Implication *}
lemma sep_implI:
assumes a: "\<And>h'. \<lbrakk> h ## h'; P h' \<rbrakk> \<Longrightarrow> Q (h + h')"
shows "(P \<longrightarrow>* Q) h"
unfolding sep_impl_def by (auto elim: a)
lemma sep_implD:
"(x \<longrightarrow>* y) h \<Longrightarrow> \<forall>h'. h ## h' \<and> x h' \<longrightarrow> y (h + h')"
by (force simp: sep_impl_def)
lemma sep_implE:
"(x \<longrightarrow>* y) h \<Longrightarrow> (\<forall>h'. h ## h' \<and> x h' \<longrightarrow> y (h + h') \<Longrightarrow> Q) \<Longrightarrow> Q"
by (auto dest: sep_implD)
lemma sep_impl_sep_true [simp]:
"(P \<longrightarrow>* sep_true) = sep_true"
by (force intro!: sep_implI ext)
lemma sep_impl_sep_false [simp]:
"(sep_false \<longrightarrow>* P) = sep_true"
by (force intro!: sep_implI ext)
lemma sep_impl_sep_true_P:
"(sep_true \<longrightarrow>* P) h \<Longrightarrow> P h"
by (clarsimp dest!: sep_implD elim!: allE[where x=0])
lemma sep_impl_sep_true_false [simp]:
"(sep_true \<longrightarrow>* sep_false) = sep_false"
by (force intro!: ext dest: sep_impl_sep_true_P)
lemma sep_conj_sep_impl:
"\<lbrakk> P h; \<And>h. (P ** Q) h \<Longrightarrow> R h \<rbrakk> \<Longrightarrow> (Q \<longrightarrow>* R) h"
proof (rule sep_implI)
fix h' h
assume "P h" and "h ## h'" and "Q h'"
hence "(P ** Q) (h + h')" by (force intro: sep_conjI)
moreover assume "\<And>h. (P ** Q) h \<Longrightarrow> R h"
ultimately show "R (h + h')" by simp
qed
lemma sep_conj_sep_impl2:
"\<lbrakk> (P ** Q) h; \<And>h. P h \<Longrightarrow> (Q \<longrightarrow>* R) h \<rbrakk> \<Longrightarrow> R h"
by (force dest: sep_implD elim: sep_conjE)
lemma sep_conj_sep_impl_sep_conj2:
"(P ** R) h \<Longrightarrow> (P ** (Q \<longrightarrow>* (Q ** R))) h"
by (erule (1) sep_conj_impl, erule sep_conj_sep_impl, simp add: sep_conj_ac)
subsection {* Pure assertions *}
definition
pure :: "('a \<Rightarrow> bool) \<Rightarrow> bool" where
"pure P \<equiv> \<forall>h h'. P h = P h'"
lemma pure_sep_true:
"pure sep_true"
by (simp add: pure_def)
lemma pure_sep_false:
"pure sep_false"
by (simp add: pure_def)
lemma pure_split:
"pure P = (P = sep_true \<or> P = sep_false)"
by (force simp: pure_def intro!: ext)
lemma pure_sep_conj:
"\<lbrakk> pure P; pure Q \<rbrakk> \<Longrightarrow> pure (P \<and>* Q)"
by (force simp: pure_split)
lemma pure_sep_impl:
"\<lbrakk> pure P; pure Q \<rbrakk> \<Longrightarrow> pure (P \<longrightarrow>* Q)"
by (force simp: pure_split)
lemma pure_conj_sep_conj:
"\<lbrakk> (P and Q) h; pure P \<or> pure Q \<rbrakk> \<Longrightarrow> (P \<and>* Q) h"
by (metis pure_def sep_add_zero sep_conjI sep_conj_commute sep_disj_zero)
lemma pure_sep_conj_conj:
"\<lbrakk> (P \<and>* Q) h; pure P; pure Q \<rbrakk> \<Longrightarrow> (P and Q) h"
by (force simp: pure_split)
lemma pure_conj_sep_conj_assoc:
"pure P \<Longrightarrow> ((P and Q) \<and>* R) = (P and (Q \<and>* R))"
by (auto simp: pure_split)
lemma pure_sep_impl_impl:
"\<lbrakk> (P \<longrightarrow>* Q) h; pure P \<rbrakk> \<Longrightarrow> P h \<longrightarrow> Q h"
by (force simp: pure_split dest: sep_impl_sep_true_P)
lemma pure_impl_sep_impl:
"\<lbrakk> P h \<longrightarrow> Q h; pure P; pure Q \<rbrakk> \<Longrightarrow> (P \<longrightarrow>* Q) h"
by (force simp: pure_split)
lemma pure_conj_right: "(Q \<and>* (\<langle>P'\<rangle> and Q')) = (\<langle>P'\<rangle> and (Q \<and>* Q'))"
by (rule ext, rule, rule, clarsimp elim!: sep_conjE)
(erule sep_conj_impl, auto)
lemma pure_conj_right': "(Q \<and>* (P' and \<langle>Q'\<rangle>)) = (\<langle>Q'\<rangle> and (Q \<and>* P'))"
by (simp add: conj_comms pure_conj_right)
lemma pure_conj_left: "((\<langle>P'\<rangle> and Q') \<and>* Q) = (\<langle>P'\<rangle> and (Q' \<and>* Q))"
by (simp add: pure_conj_right sep_conj_ac)
lemma pure_conj_left': "((P' and \<langle>Q'\<rangle>) \<and>* Q) = (\<langle>Q'\<rangle> and (P' \<and>* Q))"
by (subst conj_comms, subst pure_conj_left, simp)
lemmas pure_conj = pure_conj_right pure_conj_right' pure_conj_left
pure_conj_left'
declare pure_conj[simp add]
subsection {* Intuitionistic assertions *}
definition intuitionistic :: "('a \<Rightarrow> bool) \<Rightarrow> bool" where
"intuitionistic P \<equiv> \<forall>h h'. P h \<and> h \<preceq> h' \<longrightarrow> P h'"
lemma intuitionisticI:
"(\<And>h h'. \<lbrakk> P h; h \<preceq> h' \<rbrakk> \<Longrightarrow> P h') \<Longrightarrow> intuitionistic P"
by (unfold intuitionistic_def, fast)
lemma intuitionisticD:
"\<lbrakk> intuitionistic P; P h; h \<preceq> h' \<rbrakk> \<Longrightarrow> P h'"
by (unfold intuitionistic_def, fast)
lemma pure_intuitionistic:
"pure P \<Longrightarrow> intuitionistic P"
by (clarsimp simp: intuitionistic_def pure_def, fast)
lemma intuitionistic_conj:
"\<lbrakk> intuitionistic P; intuitionistic Q \<rbrakk> \<Longrightarrow> intuitionistic (P and Q)"
by (force intro: intuitionisticI dest: intuitionisticD)
lemma intuitionistic_disj:
"\<lbrakk> intuitionistic P; intuitionistic Q \<rbrakk> \<Longrightarrow> intuitionistic (P or Q)"
by (force intro: intuitionisticI dest: intuitionisticD)
lemma intuitionistic_forall:
"(\<And>x. intuitionistic (P x)) \<Longrightarrow> intuitionistic (ALLS x. P x)"
by (force intro: intuitionisticI dest: intuitionisticD)
lemma intuitionistic_exists:
"(\<And>x. intuitionistic (P x)) \<Longrightarrow> intuitionistic (EXS x. P x)"
by (force intro: intuitionisticI dest: intuitionisticD)
lemma intuitionistic_sep_conj_sep_true:
"intuitionistic (sep_true \<and>* P)"
proof (rule intuitionisticI)
fix h h' r
assume a: "(sep_true \<and>* P) h"
then obtain x y where P: "P y" and h: "h = x + y" and xyd: "x ## y"
by - (drule sep_conjD, clarsimp)
moreover assume a2: "h \<preceq> h'"
then obtain z where h': "h' = h + z" and hzd: "h ## z"
by (clarsimp simp: sep_substate_def)
moreover have "(P \<and>* sep_true) (y + (x + z))"
using P h hzd xyd
by (metis sep_add_disjI1 sep_disj_commute sep_conjI)
ultimately show "(sep_true \<and>* P) h'" using hzd
by (auto simp: sep_conj_commute sep_add_ac dest!: sep_disj_addD)
qed
lemma intuitionistic_sep_impl_sep_true:
"intuitionistic (sep_true \<longrightarrow>* P)"
proof (rule intuitionisticI)
fix h h'
assume imp: "(sep_true \<longrightarrow>* P) h" and hh': "h \<preceq> h'"
from hh' obtain z where h': "h' = h + z" and hzd: "h ## z"
by (clarsimp simp: sep_substate_def)
show "(sep_true \<longrightarrow>* P) h'" using imp h' hzd
apply (clarsimp dest!: sep_implD)
apply (metis sep_add_assoc sep_add_disjD sep_disj_addI3 sep_implI)
done
qed
lemma intuitionistic_sep_conj:
assumes ip: "intuitionistic (P::('a \<Rightarrow> bool))"
shows "intuitionistic (P \<and>* Q)"
proof (rule intuitionisticI)
fix h h'
assume sc: "(P \<and>* Q) h" and hh': "h \<preceq> h'"
from hh' obtain z where h': "h' = h + z" and hzd: "h ## z"
by (clarsimp simp: sep_substate_def)
from sc obtain x y where px: "P x" and qy: "Q y"
and h: "h = x + y" and xyd: "x ## y"
by (clarsimp simp: sep_conj_def)
have "x ## z" using hzd h xyd
by (metis sep_add_disjD)
with ip px have "P (x + z)"
by (fastforce elim: intuitionisticD sep_substate_disj_add)
thus "(P \<and>* Q) h'" using h' h hzd qy xyd
by (metis (full_types) sep_add_commute sep_add_disjD sep_add_disjI2
sep_add_left_commute sep_conjI)
qed
lemma intuitionistic_sep_impl:
assumes iq: "intuitionistic Q"
shows "intuitionistic (P \<longrightarrow>* Q)"
proof (rule intuitionisticI)
fix h h'
assume imp: "(P \<longrightarrow>* Q) h" and hh': "h \<preceq> h'"
from hh' obtain z where h': "h' = h + z" and hzd: "h ## z"
by (clarsimp simp: sep_substate_def)
{
fix x
assume px: "P x" and hzx: "h + z ## x"
have "h + x \<preceq> h + x + z" using hzx hzd
by (metis sep_add_disjI1 sep_substate_def)
with imp hzd iq px hzx
have "Q (h + z + x)"
by (metis intuitionisticD sep_add_assoc sep_add_ac sep_add_disjD sep_implE)
}
with imp h' hzd iq show "(P \<longrightarrow>* Q) h'"
by (fastforce intro: sep_implI)
qed
lemma strongest_intuitionistic:
"\<not> (\<exists>Q. (\<forall>h. (Q h \<longrightarrow> (P \<and>* sep_true) h)) \<and> intuitionistic Q \<and>
Q \<noteq> (P \<and>* sep_true) \<and> (\<forall>h. P h \<longrightarrow> Q h))"
by (fastforce intro!: ext sep_substate_disj_add
dest!: sep_conjD intuitionisticD)
lemma weakest_intuitionistic:
"\<not> (\<exists>Q. (\<forall>h. ((sep_true \<longrightarrow>* P) h \<longrightarrow> Q h)) \<and> intuitionistic Q \<and>
Q \<noteq> (sep_true \<longrightarrow>* P) \<and> (\<forall>h. Q h \<longrightarrow> P h))"
apply (clarsimp intro!: ext)
apply (rule iffI)
apply (rule sep_implI)
apply (drule_tac h="x" and h'="x + h'" in intuitionisticD)
apply (clarsimp simp: sep_add_ac sep_substate_disj_add)+
done
lemma intuitionistic_sep_conj_sep_true_P:
"\<lbrakk> (P \<and>* sep_true) s; intuitionistic P \<rbrakk> \<Longrightarrow> P s"
by (force dest: intuitionisticD elim: sep_conjE sep_substate_disj_add)
lemma intuitionistic_sep_conj_sep_true_simp:
"intuitionistic P \<Longrightarrow> (P \<and>* sep_true) = P"
by (fast intro!: sep_conj_sep_true ext
elim: intuitionistic_sep_conj_sep_true_P)
lemma intuitionistic_sep_impl_sep_true_P:
"\<lbrakk> P h; intuitionistic P \<rbrakk> \<Longrightarrow> (sep_true \<longrightarrow>* P) h"
by (force intro!: sep_implI dest: intuitionisticD
intro: sep_substate_disj_add)
lemma intuitionistic_sep_impl_sep_true_simp:
"intuitionistic P \<Longrightarrow> (sep_true \<longrightarrow>* P) = P"
by (fast intro!: ext
elim: sep_impl_sep_true_P intuitionistic_sep_impl_sep_true_P)
subsection {* Strictly exact assertions *}
definition strictly_exact :: "('a \<Rightarrow> bool) \<Rightarrow> bool" where
"strictly_exact P \<equiv> \<forall>h h'. P h \<and> P h' \<longrightarrow> h = h'"
lemma strictly_exactD:
"\<lbrakk> strictly_exact P; P h; P h' \<rbrakk> \<Longrightarrow> h = h'"
by (unfold strictly_exact_def, fast)
lemma strictly_exactI:
"(\<And>h h'. \<lbrakk> P h; P h' \<rbrakk> \<Longrightarrow> h = h') \<Longrightarrow> strictly_exact P"
by (unfold strictly_exact_def, fast)
lemma strictly_exact_sep_conj:
"\<lbrakk> strictly_exact P; strictly_exact Q \<rbrakk> \<Longrightarrow> strictly_exact (P \<and>* Q)"
apply (rule strictly_exactI)
apply (erule sep_conjE)+
apply (drule_tac h="x" and h'="xa" in strictly_exactD, assumption+)
apply (drule_tac h="y" and h'="ya" in strictly_exactD, assumption+)
apply clarsimp
done
lemma strictly_exact_conj_impl:
"\<lbrakk> (Q \<and>* sep_true) h; P h; strictly_exact Q \<rbrakk> \<Longrightarrow> (Q \<and>* (Q \<longrightarrow>* P)) h"
by (force intro: sep_conjI sep_implI dest: strictly_exactD elim!: sep_conjE
simp: sep_add_commute sep_add_assoc)
end
section {* Separation Algebra with Stronger, but More Intuitive Disjunction Axiom *}
class stronger_sep_algebra = pre_sep_algebra +
assumes sep_add_disj_eq [simp]: "y ## z \<Longrightarrow> x ## y + z = (x ## y \<and> x ## z)"
begin
lemma sep_disj_add_eq [simp]: "x ## y \<Longrightarrow> x + y ## z = (x ## z \<and> y ## z)"
by (metis sep_add_disj_eq sep_disj_commute)
subclass sep_algebra by default auto
end
interpretation sep: ab_semigroup_mult "op **"
by unfold_locales (simp add: sep_conj_ac)+
interpretation sep: comm_monoid "op **" \<box>
by unfold_locales simp
interpretation sep: comm_monoid_mult "op **" \<box>
by unfold_locales simp
section {* Folding separating conjunction over lists and sets of predicates *}
definition
sep_list_conj :: "('a::sep_algebra \<Rightarrow> bool) list \<Rightarrow> ('a \<Rightarrow> bool)" where
"sep_list_conj Ps \<equiv> foldl (op **) \<box> Ps"
abbreviation
sep_map_list_conj :: "('b \<Rightarrow> 'a::sep_algebra \<Rightarrow> bool) \<Rightarrow> 'b list \<Rightarrow> ('a \<Rightarrow> bool)"
where
"sep_map_list_conj g S \<equiv> sep_list_conj (map g S)"
abbreviation
sep_map_set_conj :: "('b \<Rightarrow> 'a::sep_algebra \<Rightarrow> bool) \<Rightarrow> 'b set \<Rightarrow> ('a \<Rightarrow> bool)"
where
"sep_map_set_conj g S \<equiv> sep.setprod g S"
definition
sep_set_conj :: "('a::sep_algebra \<Rightarrow> bool) set \<Rightarrow> ('a \<Rightarrow> bool)" where
"sep_set_conj S \<equiv> sep.setprod id S"
(* Notation. *)
consts
sep_conj_lifted :: "'b \<Rightarrow> ('a::sep_algebra \<Rightarrow> bool)" ("\<And>* _" [60] 90)
notation (latex output) sep_conj_lifted ("\<And>\<^sup>* _" [60] 90)
notation (latex output) sep_map_list_conj ("\<And>\<^sup>* _" [60] 90)
adhoc_overloading
sep_conj_lifted sep_list_conj
adhoc_overloading
sep_conj_lifted sep_set_conj
(* FIXME. Add notation for sep_map_list_conj, and consider unifying with sep_map_set_conj. *)
text{* Now: lot's of fancy syntax. First, @{term "sep_map_set_conj (%x. g) A"} is
written @{text"\<And>+x\<in>A. g"}. *}
(* Clagged from Big_Operators. *)
syntax
"_sep_map_set_conj" :: "pttrn => 'a set => 'b => 'b::comm_monoid_add" ("(3SETSEPCONJ _:_. _)" [0, 51, 10] 10)
syntax (xsymbols)
"_sep_map_set_conj" :: "pttrn => 'a set => 'b => 'b::comm_monoid_add" ("(3\<And>*_\<in>_. _)" [0, 51, 10] 10)
syntax (HTML output)
"_sep_map_set_conj" :: "pttrn => 'a set => 'b => 'b::comm_monoid_add" ("(3\<And>*_\<in>_. _)" [0, 51, 10] 10)
syntax (latex output)
"_sep_map_set_conj" :: "pttrn => 'a set => 'b => 'b::comm_monoid_add" ("(3\<And>\<^sup>*(00\<^bsub>_\<in>_\<^esub>) _)" [0, 51, 10] 10)
translations -- {* Beware of argument permutation! *}
"SETSEPCONJ x:A. g" == "CONST sep_map_set_conj (%x. g) A"
"\<And>* x\<in>A. g" == "CONST sep_map_set_conj (%x. g) A"
text{* Instead of @{term"\<And>*x\<in>{x. P}. g"} we introduce the shorter
@{text"\<And>+x|P. g"}. *}
syntax
"_qsep_map_set_conj" :: "pttrn \<Rightarrow> bool \<Rightarrow> 'a \<Rightarrow> 'a" ("(3SETSEPCONJ _ |/ _./ _)" [0,0,10] 10)
syntax (xsymbols)
"_qsep_map_set_conj" :: "pttrn \<Rightarrow> bool \<Rightarrow> 'a \<Rightarrow> 'a" ("(3\<And>*_ | (_)./ _)" [0,0,10] 10)
syntax (HTML output)
"_qsep_map_set_conj" :: "pttrn \<Rightarrow> bool \<Rightarrow> 'a \<Rightarrow> 'a" ("(3\<And>*_ | (_)./ _)" [0,0,10] 10)
syntax (latex output)
"_qsep_map_set_conj" :: "pttrn \<Rightarrow> bool \<Rightarrow> 'a \<Rightarrow> 'a" ("(3\<And>\<^sup>*(00\<^bsub>_ | (_)\<^esub>) /_)" [0,0,10] 10)
translations
"SETSEPCONJ x|P. g" => "CONST sep_map_set_conj (%x. g) {x. P}"
"\<And>*x|P. g" => "CONST sep_map_set_conj (%x. g) {x. P}"
print_translation {*
let
fun setsepconj_tr' [Abs (x, Tx, t), Const (@{const_syntax Collect}, _) $ Abs (y, Ty, P)] =
if x <> y then raise Match
else
let
val x' = Syntax_Trans.mark_bound_body (x, Tx);
val t' = subst_bound (x', t);
val P' = subst_bound (x', P);
in
Syntax.const @{syntax_const "_qsep_map_set_conj"} $ Syntax_Trans.mark_bound_abs (x, Tx) $ P' $ t'
end
| setsepconj_tr' _ = raise Match;
in [(@{const_syntax sep_map_set_conj}, K setsepconj_tr')] end
*}
(* FIXME. This is not needed, but gives lemmas directly on sep_map_set_conj,
rather than needing to expand the definition and use rules about setprod.
*)
interpretation sep: comm_monoid_mult "op \<and>*" \<box>
by unfold_locales (simp add: sep.setprod_def)
interpretation sep: folding "op \<and>*" \<box>
by unfold_locales (simp add: comp_def sep_conj_ac)
print_theorems (* FIXME, remove. We get all of these lemmas. *)
lemma "\<And>* [\<box>,P] = P"
by (simp add: sep_list_conj_def)
lemma "\<And>* {\<box>} = \<box>"
by (simp add: sep_set_conj_def)
lemma "\<And>* {P,\<box>} = P"
apply (cases "P = \<box>")
apply (auto simp: sep_set_conj_def)
done
lemma "(\<And>* x\<in>{0,1::nat}. if x=0 then \<box> else P) = P"
by auto
lemma map_sep_list_conj_cong:
"(\<And>x. x \<in> set xs \<Longrightarrow> f x = g x) \<Longrightarrow> \<And>* map f xs = \<And>* map g xs"
by (metis map_cong)
lemma sep_list_conj_Nil [simp]: "\<And>* [] = \<box>"
by (simp add: sep_list_conj_def)
(* apparently these two are rarely used and had to be removed from List.thy *)
lemma (in semigroup) foldl_assoc:
shows "(foldl f (f x y) zs) = (f x (foldl f y zs))"
by (induct zs arbitrary: y) (simp_all add:assoc)
lemma (in monoid) foldl_absorb1:
shows "f x (foldl f 1 zs) = foldl f x zs"
by (induct zs) (simp_all add:foldl_assoc)
lemma sep_list_conj_Cons [simp]: "\<And>* (x#xs) = (x ** \<And>* xs)"
by (simp add: sep_list_conj_def sep.foldl_absorb1)
lemma sep_list_conj_append [simp]: "\<And>* (xs @ ys) = (\<And>* xs ** \<And>* ys)"
by (simp add: sep_list_conj_def sep.foldl_absorb1)
lemma sep_list_conj_map_append:
"\<And>* map f (xs @ ys) = (\<And>* map f xs \<and>* \<And>* map f ys)"
by (metis map_append sep_list_conj_append)
lemma (in comm_monoid) foldl_map_filter:
"foldl f 1 (map P (filter t xs)) *
foldl f 1 (map P (filter (not t) xs))
= foldl f 1 (map P xs)"
proof (induct xs)
case Nil thus ?case by clarsimp
next
case (Cons x xs)
hence IH: "foldl f 1 (map P xs) =
foldl f 1 (map P (filter t xs)) *
foldl f 1 (map P [x\<leftarrow>xs . \<not> t x])"
by (simp only: eq_commute)
have foldl_Cons':
"\<And>x xs. foldl f 1 (x # xs) = f x (foldl f 1 xs)"
by (simp, subst foldl_absorb1[symmetric], rule refl)
{ assume "t x"
hence ?case by (auto simp del: foldl_Cons simp add: foldl_Cons' IH ac_simps)
} moreover {
assume "\<not> t x"
hence ?case by (auto simp del: foldl_Cons simp add: foldl_Cons' IH ac_simps)
}
ultimately show ?case by blast
qed
lemma sep_list_con_map_filter:
"(\<And>* map P (filter t xs) \<and>* \<And>* map P (filter (not t) xs))
= \<And>* map P xs"
apply (simp add: sep_list_conj_def)
apply (rule sep.foldl_map_filter)
done
lemma union_filter:
"({x \<in> xs. P x} \<union> {x \<in> xs. \<not> P x}) = xs"
by fast
lemma sep_map_set_conj_restrict:
"finite xs \<Longrightarrow>
sep_map_set_conj P xs =
(sep_map_set_conj P {x \<in> xs. t x} \<and>*
sep_map_set_conj P {x \<in> xs. \<not> t x})"
by (subst sep.setprod.union_disjoint [symmetric], (fastforce simp: union_filter)+)
lemma (in comm_monoid) foldl_map_add:
"foldl f 1 (map (\<lambda>x. P x * Q x) xs) =
(foldl f 1 (map P xs) * foldl f 1 (map Q xs))"
apply (induct xs)
apply clarsimp
apply simp
by (metis (full_types) commute foldl_absorb1 foldl_assoc)
lemma sep_list_conj_map_add:
"\<And>* map (\<lambda>x. f x \<and>* g x) xs = (\<And>* map f xs \<and>* \<And>* map g xs)"
apply (simp add: sep_list_conj_def)
apply (rule sep.foldl_map_add)
done
lemma filter_empty:
"x \<notin> set xs \<Longrightarrow> filter (op = x) xs = []"
by (induct xs, clarsimp+)
lemma filter_singleton:
"\<lbrakk>x \<in> set xs; distinct xs\<rbrakk> \<Longrightarrow> [x'\<leftarrow>xs . x = x'] = [x]"
by (induct xs, auto simp: filter_empty)
lemma remove1_filter:
"distinct xs \<Longrightarrow> remove1 x xs = filter (\<lambda>y. x \<noteq> y) xs"
apply (induct xs)
apply simp
apply clarsimp
apply (rule sym, rule filter_True)
apply clarsimp
done
lemma (in comm_monoid) foldl_map_remove1:
"x \<in> set xs \<Longrightarrow> foldl f 1 (map P xs) = f (P x) (foldl f 1 (map P (remove1 x xs)))"
apply (induction xs, simp)
apply clarsimp
by (metis foldl_absorb1 left_commute)
lemma sep_list_conj_map_remove1:
"x \<in> set xs \<Longrightarrow> \<And>* map P xs = (P x \<and>* \<And>* map P (remove1 x xs))"
apply (simp add: sep_list_conj_def)
apply (erule sep.foldl_map_remove1)
done
lemma sep_map_take_Suc:
"i < length xs \<Longrightarrow>
\<And>* map P (take (Suc i) xs) = (\<And>* map P (take i xs) \<and>* P (xs ! i))"
by (subst take_Suc_conv_app_nth, simp+)
lemma sep_conj_map_split:
"(\<And>* map f xs \<and>* f a \<and>* \<And>* map f ys)
= (\<And>* map f (xs @ a # ys))"
by (metis list.map(2) map_append sep_list_conj_Cons sep_list_conj_append)
(*
* Separation predicates on sets. *
*)
lemma sep_map_set_conj_cong:
"\<lbrakk>P = Q; xs = ys\<rbrakk> \<Longrightarrow> sep_map_set_conj P xs = sep_map_set_conj Q ys"
by (simp)
lemma sep_set_conj_empty [simp]:
"sep_set_conj {} = \<box>"
by (simp add: sep_set_conj_def)
(* FIXME: We should be able to pull this from the "comm_monoid_big"
* or "comm_monoid_add" locales, but I can't work out how... *)
lemma sep_map_set_conj_reindex_cong:
"\<lbrakk>inj_on f A; B = f ` A; \<And>a. a \<in> A \<Longrightarrow> g a = h (f a)\<rbrakk>
\<Longrightarrow> sep_map_set_conj h B = sep_map_set_conj g A"
by (simp add: sep.setprod.reindex)
lemma sep_list_conj_sep_map_set_conj:
"distinct xs
\<Longrightarrow> \<And>* (map P xs) = (\<And>* x \<in> set xs. P x)"
by (induct xs, simp_all)
lemma sep_list_conj_sep_set_conj:
"\<lbrakk>distinct xs; inj_on P (set xs)\<rbrakk>
\<Longrightarrow> \<And>* (map P xs) = \<And>* (P ` set xs)"
apply (subst sep_list_conj_sep_map_set_conj, assumption)
apply (clarsimp simp: sep_set_conj_def sep.setprod.reindex)
done
lemma sep_map_set_conj_sep_list_conj:
"finite A \<Longrightarrow>
\<exists>xs. set xs = A \<and> distinct xs \<and> sep_map_set_conj P A = \<And>* map P xs"
apply (frule finite_distinct_list)
apply (erule exE)
apply (rule_tac x=xs in exI)
apply clarsimp
apply (erule sep_list_conj_sep_map_set_conj [symmetric])
done
lemma sep_list_conj_eq:
"\<lbrakk>distinct xs; distinct ys; set xs = set ys\<rbrakk> \<Longrightarrow>
\<And>* (map P xs) = \<And>* (map P ys)"
apply (drule sep_list_conj_sep_map_set_conj [where P=P])
apply (drule sep_list_conj_sep_map_set_conj [where P=P])
apply simp
done
lemma sep_list_conj_impl:
"\<lbrakk> list_all2 (\<lambda>x y. \<forall>s. x s \<longrightarrow> y s) xs ys; (\<And>* xs) s \<rbrakk> \<Longrightarrow> (\<And>* ys) s"
apply (induct arbitrary: s rule: list_all2_induct)
apply simp
apply simp
apply (erule sep_conj_impl, simp_all)
done
lemma sep_list_conj_exists:
"(\<exists>x. (\<And>* map (\<lambda>y s. P x y s) ys) s) \<Longrightarrow> ((\<And>* map (\<lambda>y s. \<exists>x. P x y s) ys) s)"
apply clarsimp
apply (erule sep_list_conj_impl[rotated])
apply (rule list_all2I, simp_all)
by (fastforce simp: in_set_zip)
lemma sep_list_conj_map_impl:
"\<lbrakk>\<And>s x. \<lbrakk>x \<in> set xs; P x s\<rbrakk> \<Longrightarrow> Q x s; (\<And>* map P xs) s\<rbrakk>
\<Longrightarrow> (\<And>* map Q xs) s"
apply (erule sep_list_conj_impl[rotated])
apply (rule list_all2I, simp_all)
by (fastforce simp: in_set_zip)
lemma sep_map_set_conj_impl:
"\<lbrakk>sep_map_set_conj P A s; \<And>s x. \<lbrakk>x \<in> A; P x s\<rbrakk> \<Longrightarrow> Q x s; finite A\<rbrakk>
\<Longrightarrow> sep_map_set_conj Q A s"
apply (frule sep_map_set_conj_sep_list_conj [where P=P])
apply (drule sep_map_set_conj_sep_list_conj [where P=Q])
by (metis sep_list_conj_map_impl sep_list_conj_sep_map_set_conj)
lemma set_sub_sub:
"\<lbrakk>zs \<subseteq> ys\<rbrakk> \<Longrightarrow> (xs - zs) - (ys - zs) = (xs - ys)"
by blast
lemma sep_map_set_conj_sub_sub_disjoint:
"\<lbrakk>finite xs; zs \<subseteq> ys; ys \<subseteq> xs\<rbrakk>
\<Longrightarrow> sep_map_set_conj P (xs - zs) = (sep_map_set_conj P (xs - ys) \<and>* sep_map_set_conj P (ys - zs))"
apply (cut_tac sep.setprod.subset_diff [where A="xs-zs" and B="ys-zs" and g=P])
apply (subst (asm) set_sub_sub, fast+)
done
lemma foldl_use_filter_map:
"foldl op \<and>* Q (map (\<lambda>x. if T x then P x else \<box>) xs) =
foldl op \<and>* Q (map P (filter T xs))"
by (induct xs arbitrary: Q, simp_all)
lemma sep_list_conj_filter_map:
"\<And>* (map (\<lambda>x. if T x then P x else \<box>) xs) =
\<And>* (map P (filter T xs))"
by (clarsimp simp: sep_list_conj_def foldl_use_filter_map)
lemma sep_map_set_conj_restrict_predicate:
"finite A
\<Longrightarrow> (\<And>* x\<in>A. if T x then P x else \<box>) =
(\<And>* x\<in>(Set.filter T A). P x)"
apply (drule finite_distinct_list)
apply (clarsimp)
apply (subst filter_set)
apply (subst sep_list_conj_sep_map_set_conj [symmetric], simp)+
apply (rule sep_list_conj_filter_map)
done
lemma distinct_filters:
"\<lbrakk>distinct xs; \<And>x. (f x \<and> g x) = False\<rbrakk> \<Longrightarrow>
set [x\<leftarrow>xs . f x \<or> g x] = set [x\<leftarrow>xs . f x] \<union> set [x\<leftarrow>xs . g x]"
by auto
lemma sep_list_conj_distinct_filters:
"\<lbrakk>distinct xs; \<And>x. (f x \<and> g x) = False\<rbrakk> \<Longrightarrow>
\<And>* map P [x\<leftarrow>xs . f x \<or> g x] = (\<And>* map P [x\<leftarrow>xs . f x] \<and>* \<And>* map P [x\<leftarrow>xs . g x])"
apply (subst sep_list_conj_sep_map_set_conj, simp)+
apply (subst distinct_filters, simp+)
apply (subst sep.setprod.union_disjoint, auto)
done
lemma sep_map_set_conj_set_disjoint:
"\<lbrakk>finite {x. P x}; finite {x. Q x}; \<And>x. (P x \<and> Q x) = False\<rbrakk>
\<Longrightarrow> sep_map_set_conj g {x. P x \<or> Q x} =
(sep_map_set_conj g {x. P x} \<and>* sep_map_set_conj g {x. Q x})"
apply (subst sep.setprod.union_disjoint [symmetric], simp+)
apply blast
apply simp
by (metis Collect_disj_eq)
section {* Separation Algebra with a Cancellative Monoid (for completeness) *}
text {*
Separation algebra with a cancellative monoid. The results of being a precise
assertion (distributivity over separating conjunction) require this.
although we never actually use this property in our developments, we keep
it here for completeness.
*}
class cancellative_sep_algebra = sep_algebra +
assumes sep_add_cancelD: "\<lbrakk> x + z = y + z ; x ## z ; y ## z \<rbrakk> \<Longrightarrow> x = y"
begin
definition
(* In any heap, there exists at most one subheap for which P holds *)
precise :: "('a \<Rightarrow> bool) \<Rightarrow> bool" where
"precise P = (\<forall>h hp hp'. hp \<preceq> h \<and> P hp \<and> hp' \<preceq> h \<and> P hp' \<longrightarrow> hp = hp')"
lemma "precise (op = s)"
by (metis (full_types) precise_def)
lemma sep_add_cancel:
"x ## z \<Longrightarrow> y ## z \<Longrightarrow> (x + z = y + z) = (x = y)"
by (metis sep_add_cancelD)
lemma precise_distribute:
"precise P = (\<forall>Q R. ((Q and R) \<and>* P) = ((Q \<and>* P) and (R \<and>* P)))"
proof (rule iffI)
assume pp: "precise P"
{
fix Q R
fix h hp hp' s
{ assume a: "((Q and R) \<and>* P) s"
hence "((Q \<and>* P) and (R \<and>* P)) s"
by (fastforce dest!: sep_conjD elim: sep_conjI)
}
moreover
{ assume qs: "(Q \<and>* P) s" and qr: "(R \<and>* P) s"
from qs obtain x y where sxy: "s = x + y" and xy: "x ## y"
and x: "Q x" and y: "P y"
by (fastforce dest!: sep_conjD)
from qr obtain x' y' where sxy': "s = x' + y'" and xy': "x' ## y'"
and x': "R x'" and y': "P y'"
by (fastforce dest!: sep_conjD)
from sxy have ys: "y \<preceq> x + y" using xy
by (fastforce simp: sep_substate_disj_add' sep_disj_commute)
from sxy' have ys': "y' \<preceq> x' + y'" using xy'
by (fastforce simp: sep_substate_disj_add' sep_disj_commute)
from pp have yy: "y = y'" using sxy sxy' xy xy' y y' ys ys'
by (fastforce simp: precise_def)
hence "x = x'" using sxy sxy' xy xy'
by (fastforce dest!: sep_add_cancelD)
hence "((Q and R) \<and>* P) s" using sxy x x' yy y' xy'
by (fastforce intro: sep_conjI)
}
ultimately
have "((Q and R) \<and>* P) s = ((Q \<and>* P) and (R \<and>* P)) s" using pp by blast
}
thus "\<forall>Q R. ((Q and R) \<and>* P) = ((Q \<and>* P) and (R \<and>* P))" by (blast intro!: ext)
next
assume a: "\<forall>Q R. ((Q and R) \<and>* P) = ((Q \<and>* P) and (R \<and>* P))"
thus "precise P"
proof (clarsimp simp: precise_def)
fix h hp hp' Q R
assume hp: "hp \<preceq> h" and hp': "hp' \<preceq> h" and php: "P hp" and php': "P hp'"
obtain z where hhp: "h = hp + z" and hpz: "hp ## z" using hp
by (clarsimp simp: sep_substate_def)
obtain z' where hhp': "h = hp' + z'" and hpz': "hp' ## z'" using hp'
by (clarsimp simp: sep_substate_def)
have h_eq: "z' + hp' = z + hp" using hhp hhp' hpz hpz'
by (fastforce simp: sep_add_ac)
from hhp hhp' a hpz hpz' h_eq
have "\<forall>Q R. ((Q and R) \<and>* P) (z + hp) = ((Q \<and>* P) and (R \<and>* P)) (z' + hp')"
by (fastforce simp: h_eq sep_add_ac sep_conj_commute)
hence "((op = z and op = z') \<and>* P) (z + hp) =
((op = z \<and>* P) and (op = z' \<and>* P)) (z' + hp')" by blast
thus "hp = hp'" using php php' hpz hpz' h_eq
by (fastforce dest!: iffD2 cong: conj_cong
simp: sep_add_ac sep_add_cancel sep_conj_def)
qed
qed
lemma strictly_precise: "strictly_exact P \<Longrightarrow> precise P"
by (metis precise_def strictly_exactD)
end
end