src/HOL/HOLCF/Tr.thy
changeset 67312 0d25e02759b7
parent 62175 8ffc4d0e652d
child 69597 ff784d5a5bfb
--- a/src/HOL/HOLCF/Tr.thy	Mon Jan 01 21:17:28 2018 +0100
+++ b/src/HOL/HOLCF/Tr.thy	Mon Jan 01 23:07:24 2018 +0100
@@ -5,107 +5,97 @@
 section \<open>The type of lifted booleans\<close>
 
 theory Tr
-imports Lift
+  imports Lift
 begin
 
 subsection \<open>Type definition and constructors\<close>
 
-type_synonym
-  tr = "bool lift"
+type_synonym tr = "bool lift"
 
 translations
-  (type) "tr" <= (type) "bool lift"
+  (type) "tr" \<leftharpoondown> (type) "bool lift"
 
-definition
-  TT :: "tr" where
-  "TT = Def True"
+definition TT :: "tr"
+  where "TT = Def True"
 
-definition
-  FF :: "tr" where
-  "FF = Def False"
+definition FF :: "tr"
+  where "FF = Def False"
 
 text \<open>Exhaustion and Elimination for type @{typ tr}\<close>
 
 lemma Exh_tr: "t = \<bottom> \<or> t = TT \<or> t = FF"
-unfolding FF_def TT_def by (induct t) auto
+  by (induct t) (auto simp: FF_def TT_def)
 
 lemma trE [case_names bottom TT FF, cases type: tr]:
   "\<lbrakk>p = \<bottom> \<Longrightarrow> Q; p = TT \<Longrightarrow> Q; p = FF \<Longrightarrow> Q\<rbrakk> \<Longrightarrow> Q"
-unfolding FF_def TT_def by (induct p) auto
+  by (induct p) (auto simp: FF_def TT_def)
 
 lemma tr_induct [case_names bottom TT FF, induct type: tr]:
-  "\<lbrakk>P \<bottom>; P TT; P FF\<rbrakk> \<Longrightarrow> P x"
-by (cases x) simp_all
+  "P \<bottom> \<Longrightarrow> P TT \<Longrightarrow> P FF \<Longrightarrow> P x"
+  by (cases x) simp_all
 
 text \<open>distinctness for type @{typ tr}\<close>
 
 lemma dist_below_tr [simp]:
   "TT \<notsqsubseteq> \<bottom>" "FF \<notsqsubseteq> \<bottom>" "TT \<notsqsubseteq> FF" "FF \<notsqsubseteq> TT"
-unfolding TT_def FF_def by simp_all
+  by (simp_all add: TT_def FF_def)
 
-lemma dist_eq_tr [simp]:
-  "TT \<noteq> \<bottom>" "FF \<noteq> \<bottom>" "TT \<noteq> FF" "\<bottom> \<noteq> TT" "\<bottom> \<noteq> FF" "FF \<noteq> TT"
-unfolding TT_def FF_def by simp_all
+lemma dist_eq_tr [simp]: "TT \<noteq> \<bottom>" "FF \<noteq> \<bottom>" "TT \<noteq> FF" "\<bottom> \<noteq> TT" "\<bottom> \<noteq> FF" "FF \<noteq> TT"
+  by (simp_all add: TT_def FF_def)
 
 lemma TT_below_iff [simp]: "TT \<sqsubseteq> x \<longleftrightarrow> x = TT"
-by (induct x) simp_all
+  by (induct x) simp_all
 
 lemma FF_below_iff [simp]: "FF \<sqsubseteq> x \<longleftrightarrow> x = FF"
-by (induct x) simp_all
+  by (induct x) simp_all
 
 lemma not_below_TT_iff [simp]: "x \<notsqsubseteq> TT \<longleftrightarrow> x = FF"
-by (induct x) simp_all
+  by (induct x) simp_all
 
 lemma not_below_FF_iff [simp]: "x \<notsqsubseteq> FF \<longleftrightarrow> x = TT"
-by (induct x) simp_all
+  by (induct x) simp_all
 
 
 subsection \<open>Case analysis\<close>
 
 default_sort pcpo
 
-definition tr_case :: "'a \<rightarrow> 'a \<rightarrow> tr \<rightarrow> 'a" where
-  "tr_case = (\<Lambda> t e (Def b). if b then t else e)"
+definition tr_case :: "'a \<rightarrow> 'a \<rightarrow> tr \<rightarrow> 'a"
+  where "tr_case = (\<Lambda> t e (Def b). if b then t else e)"
 
-abbreviation
-  cifte_syn :: "[tr, 'c, 'c] \<Rightarrow> 'c"  ("(If (_)/ then (_)/ else (_))" [0, 0, 60] 60)
-where
-  "If b then e1 else e2 == tr_case\<cdot>e1\<cdot>e2\<cdot>b"
+abbreviation cifte_syn :: "[tr, 'c, 'c] \<Rightarrow> 'c"  ("(If (_)/ then (_)/ else (_))" [0, 0, 60] 60)
+  where "If b then e1 else e2 \<equiv> tr_case\<cdot>e1\<cdot>e2\<cdot>b"
 
 translations
-  "\<Lambda> (XCONST TT). t" == "CONST tr_case\<cdot>t\<cdot>\<bottom>"
-  "\<Lambda> (XCONST FF). t" == "CONST tr_case\<cdot>\<bottom>\<cdot>t"
+  "\<Lambda> (XCONST TT). t" \<rightleftharpoons> "CONST tr_case\<cdot>t\<cdot>\<bottom>"
+  "\<Lambda> (XCONST FF). t" \<rightleftharpoons> "CONST tr_case\<cdot>\<bottom>\<cdot>t"
 
 lemma ifte_thms [simp]:
   "If \<bottom> then e1 else e2 = \<bottom>"
   "If FF then e1 else e2 = e2"
   "If TT then e1 else e2 = e1"
-by (simp_all add: tr_case_def TT_def FF_def)
+  by (simp_all add: tr_case_def TT_def FF_def)
 
 
 subsection \<open>Boolean connectives\<close>
 
-definition
-  trand :: "tr \<rightarrow> tr \<rightarrow> tr" where
-  andalso_def: "trand = (\<Lambda> x y. If x then y else FF)"
-abbreviation
-  andalso_syn :: "tr \<Rightarrow> tr \<Rightarrow> tr"  ("_ andalso _" [36,35] 35)  where
-  "x andalso y == trand\<cdot>x\<cdot>y"
+definition trand :: "tr \<rightarrow> tr \<rightarrow> tr"
+  where andalso_def: "trand = (\<Lambda> x y. If x then y else FF)"
+
+abbreviation andalso_syn :: "tr \<Rightarrow> tr \<Rightarrow> tr"  ("_ andalso _" [36,35] 35)
+  where "x andalso y \<equiv> trand\<cdot>x\<cdot>y"
+
+definition tror :: "tr \<rightarrow> tr \<rightarrow> tr"
+  where orelse_def: "tror = (\<Lambda> x y. If x then TT else y)"
 
-definition
-  tror :: "tr \<rightarrow> tr \<rightarrow> tr" where
-  orelse_def: "tror = (\<Lambda> x y. If x then TT else y)"
-abbreviation
-  orelse_syn :: "tr \<Rightarrow> tr \<Rightarrow> tr"  ("_ orelse _"  [31,30] 30)  where
-  "x orelse y == tror\<cdot>x\<cdot>y"
+abbreviation orelse_syn :: "tr \<Rightarrow> tr \<Rightarrow> tr"  ("_ orelse _"  [31,30] 30)
+  where "x orelse y \<equiv> tror\<cdot>x\<cdot>y"
 
-definition
-  neg :: "tr \<rightarrow> tr" where
-  "neg = flift2 Not"
+definition neg :: "tr \<rightarrow> tr"
+  where "neg = flift2 Not"
 
-definition
-  If2 :: "[tr, 'c, 'c] \<Rightarrow> 'c" where
-  "If2 Q x y = (If Q then x else y)"
+definition If2 :: "tr \<Rightarrow> 'c \<Rightarrow> 'c \<Rightarrow> 'c"
+  where "If2 Q x y = (If Q then x else y)"
 
 text \<open>tactic for tr-thms with case split\<close>
 
@@ -119,10 +109,10 @@
   "(\<bottom> andalso y) = \<bottom>"
   "(y andalso TT) = y"
   "(y andalso y) = y"
-apply (unfold andalso_def, simp_all)
-apply (cases y, simp_all)
-apply (cases y, simp_all)
-done
+      apply (unfold andalso_def, simp_all)
+   apply (cases y, simp_all)
+  apply (cases y, simp_all)
+  done
 
 lemma orelse_thms [simp]:
   "(TT orelse y) = TT"
@@ -130,25 +120,21 @@
   "(\<bottom> orelse y) = \<bottom>"
   "(y orelse FF) = y"
   "(y orelse y) = y"
-apply (unfold orelse_def, simp_all)
-apply (cases y, simp_all)
-apply (cases y, simp_all)
-done
+      apply (unfold orelse_def, simp_all)
+   apply (cases y, simp_all)
+  apply (cases y, simp_all)
+  done
 
 lemma neg_thms [simp]:
   "neg\<cdot>TT = FF"
   "neg\<cdot>FF = TT"
   "neg\<cdot>\<bottom> = \<bottom>"
-by (simp_all add: neg_def TT_def FF_def)
+  by (simp_all add: neg_def TT_def FF_def)
 
 text \<open>split-tac for If via If2 because the constant has to be a constant\<close>
 
-lemma split_If2:
-  "P (If2 Q x y) = ((Q = \<bottom> \<longrightarrow> P \<bottom>) \<and> (Q = TT \<longrightarrow> P x) \<and> (Q = FF \<longrightarrow> P y))"
-apply (unfold If2_def)
-apply (cases Q)
-apply (simp_all)
-done
+lemma split_If2: "P (If2 Q x y) \<longleftrightarrow> ((Q = \<bottom> \<longrightarrow> P \<bottom>) \<and> (Q = TT \<longrightarrow> P x) \<and> (Q = FF \<longrightarrow> P y))"
+  by (cases Q) (simp_all add: If2_def)
 
 (* FIXME unused!? *)
 ML \<open>
@@ -159,42 +145,34 @@
 
 subsection "Rewriting of HOLCF operations to HOL functions"
 
-lemma andalso_or:
-  "t \<noteq> \<bottom> \<Longrightarrow> ((t andalso s) = FF) = (t = FF \<or> s = FF)"
-apply (cases t)
-apply simp_all
-done
+lemma andalso_or: "t \<noteq> \<bottom> \<Longrightarrow> (t andalso s) = FF \<longleftrightarrow> t = FF \<or> s = FF"
+  by (cases t) simp_all
 
-lemma andalso_and:
-  "t \<noteq> \<bottom> \<Longrightarrow> ((t andalso s) \<noteq> FF) = (t \<noteq> FF \<and> s \<noteq> FF)"
-apply (cases t)
-apply simp_all
-done
+lemma andalso_and: "t \<noteq> \<bottom> \<Longrightarrow> ((t andalso s) \<noteq> FF) \<longleftrightarrow> t \<noteq> FF \<and> s \<noteq> FF"
+  by (cases t) simp_all
 
-lemma Def_bool1 [simp]: "(Def x \<noteq> FF) = x"
-by (simp add: FF_def)
+lemma Def_bool1 [simp]: "Def x \<noteq> FF \<longleftrightarrow> x"
+  by (simp add: FF_def)
 
-lemma Def_bool2 [simp]: "(Def x = FF) = (\<not> x)"
-by (simp add: FF_def)
+lemma Def_bool2 [simp]: "Def x = FF \<longleftrightarrow> \<not> x"
+  by (simp add: FF_def)
 
-lemma Def_bool3 [simp]: "(Def x = TT) = x"
-by (simp add: TT_def)
+lemma Def_bool3 [simp]: "Def x = TT \<longleftrightarrow> x"
+  by (simp add: TT_def)
 
-lemma Def_bool4 [simp]: "(Def x \<noteq> TT) = (\<not> x)"
-by (simp add: TT_def)
+lemma Def_bool4 [simp]: "Def x \<noteq> TT \<longleftrightarrow> \<not> x"
+  by (simp add: TT_def)
 
-lemma If_and_if:
-  "(If Def P then A else B) = (if P then A else B)"
-apply (cases "Def P")
-apply (auto simp add: TT_def[symmetric] FF_def[symmetric])
-done
+lemma If_and_if: "(If Def P then A else B) = (if P then A else B)"
+  by (cases "Def P") (auto simp add: TT_def[symmetric] FF_def[symmetric])
+
 
 subsection \<open>Compactness\<close>
 
 lemma compact_TT: "compact TT"
-by (rule compact_chfin)
+  by (rule compact_chfin)
 
 lemma compact_FF: "compact FF"
-by (rule compact_chfin)
+  by (rule compact_chfin)
 
 end