src/HOLCF/Cprod.thy
changeset 15576 efb95d0d01f7
child 15577 e16da3068ad6
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOLCF/Cprod.thy	Fri Mar 04 23:12:36 2005 +0100
@@ -0,0 +1,493 @@
+(*  Title:      HOLCF/Cprod1.thy
+    ID:         $Id$
+    Author:     Franz Regensburger
+    License:    GPL (GNU GENERAL PUBLIC LICENSE)
+
+Partial ordering for cartesian product of HOL theory prod.thy
+*)
+
+header {* The cpo of cartesian products *}
+
+theory Cprod = Cfun:
+
+defaultsort cpo
+
+instance "*"::(sq_ord,sq_ord)sq_ord ..
+
+defs (overloaded)
+
+  less_cprod_def: "p1 << p2 == (fst p1<<fst p2 & snd p1 << snd p2)"
+
+(* ------------------------------------------------------------------------ *)
+(* less_cprod is a partial order on 'a * 'b                                 *)
+(* ------------------------------------------------------------------------ *)
+
+lemma refl_less_cprod: "(p::'a*'b) << p"
+apply (unfold less_cprod_def)
+apply simp
+done
+
+lemma antisym_less_cprod: "[|(p1::'a * 'b) << p2;p2 << p1|] ==> p1=p2"
+apply (unfold less_cprod_def)
+apply (rule injective_fst_snd)
+apply (fast intro: antisym_less)
+apply (fast intro: antisym_less)
+done
+
+lemma trans_less_cprod: 
+        "[|(p1::'a*'b) << p2;p2 << p3|] ==> p1 << p3"
+apply (unfold less_cprod_def)
+apply (rule conjI)
+apply (fast intro: trans_less)
+apply (fast intro: trans_less)
+done
+
+(* Class Instance *::(pcpo,pcpo)po *)
+
+defaultsort pcpo
+
+instance "*"::(cpo,cpo)po
+apply (intro_classes)
+apply (rule refl_less_cprod)
+apply (rule antisym_less_cprod, assumption+)
+apply (rule trans_less_cprod, assumption+)
+done
+
+(* for compatibility with old HOLCF-Version *)
+lemma inst_cprod_po: "(op <<)=(%x y. fst x<<fst y & snd x<<snd y)"
+apply (fold less_cprod_def)
+apply (rule refl)
+done
+
+lemma less_cprod4c: "(x1,y1) << (x2,y2) ==> x1 << x2 & y1 << y2"
+apply (simp add: inst_cprod_po)
+done
+
+(* ------------------------------------------------------------------------ *)
+(* type cprod is pointed                                                    *)
+(* ------------------------------------------------------------------------ *)
+
+lemma minimal_cprod: "(UU,UU)<<p"
+apply (simp (no_asm) add: inst_cprod_po)
+done
+
+lemmas UU_cprod_def = minimal_cprod [THEN minimal2UU, symmetric, standard]
+
+lemma least_cprod: "EX x::'a*'b. ALL y. x<<y"
+apply (rule_tac x = " (UU,UU) " in exI)
+apply (rule minimal_cprod [THEN allI])
+done
+
+(* ------------------------------------------------------------------------ *)
+(* Pair <_,_>  is monotone in both arguments                                *)
+(* ------------------------------------------------------------------------ *)
+
+lemma monofun_pair1: "monofun Pair"
+
+apply (unfold monofun)
+apply (intro strip)
+apply (rule less_fun [THEN iffD2])
+apply (intro strip)
+apply (simp (no_asm_simp) add: inst_cprod_po)
+done
+
+lemma monofun_pair2: "monofun(Pair x)"
+apply (unfold monofun)
+apply (simp (no_asm_simp) add: inst_cprod_po)
+done
+
+lemma monofun_pair: "[|x1<<x2; y1<<y2|] ==> (x1::'a::cpo,y1::'b::cpo)<<(x2,y2)"
+apply (rule trans_less)
+apply (erule monofun_pair1 [THEN monofunE, THEN spec, THEN spec, THEN mp, THEN less_fun [THEN iffD1, THEN spec]])
+apply (erule monofun_pair2 [THEN monofunE, THEN spec, THEN spec, THEN mp])
+done
+
+(* ------------------------------------------------------------------------ *)
+(* fst and snd are monotone                                                 *)
+(* ------------------------------------------------------------------------ *)
+
+lemma monofun_fst: "monofun fst"
+apply (unfold monofun)
+apply (intro strip)
+apply (rule_tac p = "x" in PairE)
+apply (rule_tac p = "y" in PairE)
+apply simp
+apply (erule less_cprod4c [THEN conjunct1])
+done
+
+lemma monofun_snd: "monofun snd"
+apply (unfold monofun)
+apply (intro strip)
+apply (rule_tac p = "x" in PairE)
+apply (rule_tac p = "y" in PairE)
+apply simp
+apply (erule less_cprod4c [THEN conjunct2])
+done
+
+(* ------------------------------------------------------------------------ *)
+(* the type 'a * 'b is a cpo                                                *)
+(* ------------------------------------------------------------------------ *)
+
+lemma lub_cprod: 
+"chain S ==> range S<<|(lub(range(%i. fst(S i))),lub(range(%i. snd(S i))))"
+apply (rule is_lubI)
+apply (rule ub_rangeI)
+apply (rule_tac t = "S i" in surjective_pairing [THEN ssubst])
+apply (rule monofun_pair)
+apply (rule is_ub_thelub)
+apply (erule monofun_fst [THEN ch2ch_monofun])
+apply (rule is_ub_thelub)
+apply (erule monofun_snd [THEN ch2ch_monofun])
+apply (rule_tac t = "u" in surjective_pairing [THEN ssubst])
+apply (rule monofun_pair)
+apply (rule is_lub_thelub)
+apply (erule monofun_fst [THEN ch2ch_monofun])
+apply (erule monofun_fst [THEN ub2ub_monofun])
+apply (rule is_lub_thelub)
+apply (erule monofun_snd [THEN ch2ch_monofun])
+apply (erule monofun_snd [THEN ub2ub_monofun])
+done
+
+lemmas thelub_cprod = lub_cprod [THEN thelubI, standard]
+(*
+"chain ?S1 ==>
+ lub (range ?S1) =
+ (lub (range (%i. fst (?S1 i))), lub (range (%i. snd (?S1 i))))" : thm
+
+*)
+
+lemma cpo_cprod: "chain(S::nat=>'a::cpo*'b::cpo)==>EX x. range S<<| x"
+apply (rule exI)
+apply (erule lub_cprod)
+done
+
+(* Class instance of * for class pcpo and cpo. *)
+
+instance "*" :: (cpo,cpo)cpo
+by (intro_classes, rule cpo_cprod)
+
+instance "*" :: (pcpo,pcpo)pcpo
+by (intro_classes, rule least_cprod)
+
+consts
+        cpair        :: "'a::cpo -> 'b::cpo -> ('a*'b)" (* continuous pairing *)
+        cfst         :: "('a::cpo*'b::cpo)->'a"
+        csnd         :: "('a::cpo*'b::cpo)->'b"
+        csplit       :: "('a::cpo->'b::cpo->'c::cpo)->('a*'b)->'c"
+
+syntax
+        "@ctuple"    :: "['a, args] => 'a * 'b"         ("(1<_,/ _>)")
+
+translations
+        "<x, y, z>"   == "<x, <y, z>>"
+        "<x, y>"      == "cpair$x$y"
+
+defs
+cpair_def:       "cpair  == (LAM x y.(x,y))"
+cfst_def:        "cfst   == (LAM p. fst(p))"
+csnd_def:        "csnd   == (LAM p. snd(p))"      
+csplit_def:      "csplit == (LAM f p. f$(cfst$p)$(csnd$p))"
+
+
+
+(* introduce syntax for
+
+   Let <x,y> = e1; z = E2 in E3
+
+   and
+
+   LAM <x,y,z>.e
+*)
+
+constdefs
+  CLet           :: "'a -> ('a -> 'b) -> 'b"
+  "CLet == LAM s f. f$s"
+
+
+(* syntax for Let *)
+
+nonterminals
+  Cletbinds  Cletbind
+
+syntax
+  "_Cbind"  :: "[pttrn, 'a] => Cletbind"             ("(2_ =/ _)" 10)
+  ""        :: "Cletbind => Cletbinds"               ("_")
+  "_Cbinds" :: "[Cletbind, Cletbinds] => Cletbinds"  ("_;/ _")
+  "_CLet"   :: "[Cletbinds, 'a] => 'a"               ("(Let (_)/ in (_))" 10)
+
+translations
+  "_CLet (_Cbinds b bs) e"  == "_CLet b (_CLet bs e)"
+  "Let x = a in e"          == "CLet$a$(LAM x. e)"
+
+
+(* syntax for LAM <x,y,z>.e *)
+
+syntax
+  "_LAM"    :: "[patterns, 'a => 'b] => ('a -> 'b)"  ("(3LAM <_>./ _)" [0, 10] 10)
+
+translations
+  "LAM <x,y,zs>.b"        == "csplit$(LAM x. LAM <y,zs>.b)"
+  "LAM <x,y>. LAM zs. b"  <= "csplit$(LAM x y zs. b)"
+  "LAM <x,y>.b"           == "csplit$(LAM x y. b)"
+
+syntax (xsymbols)
+  "_LAM"    :: "[patterns, 'a => 'b] => ('a -> 'b)"  ("(3\\<Lambda>()<_>./ _)" [0, 10] 10)
+
+(* for compatibility with old HOLCF-Version *)
+lemma inst_cprod_pcpo: "UU = (UU,UU)"
+apply (simp add: UU_cprod_def[folded UU_def])
+done
+
+(* ------------------------------------------------------------------------ *)
+(* continuity of (_,_) , fst, snd                                           *)
+(* ------------------------------------------------------------------------ *)
+
+lemma Cprod3_lemma1: 
+"chain(Y::(nat=>'a::cpo)) ==> 
+  (lub(range(Y)),(x::'b::cpo)) = 
+  (lub(range(%i. fst(Y i,x))),lub(range(%i. snd(Y i,x))))"
+apply (rule_tac f1 = "Pair" in arg_cong [THEN cong])
+apply (rule lub_equal)
+apply assumption
+apply (rule monofun_fst [THEN ch2ch_monofun])
+apply (rule ch2ch_fun)
+apply (rule monofun_pair1 [THEN ch2ch_monofun])
+apply assumption
+apply (rule allI)
+apply (simp (no_asm))
+apply (rule sym)
+apply (simp (no_asm))
+apply (rule lub_const [THEN thelubI])
+done
+
+lemma contlub_pair1: "contlub(Pair)"
+apply (rule contlubI)
+apply (intro strip)
+apply (rule expand_fun_eq [THEN iffD2])
+apply (intro strip)
+apply (subst lub_fun [THEN thelubI])
+apply (erule monofun_pair1 [THEN ch2ch_monofun])
+apply (rule trans)
+apply (rule_tac [2] thelub_cprod [symmetric])
+apply (rule_tac [2] ch2ch_fun)
+apply (erule_tac [2] monofun_pair1 [THEN ch2ch_monofun])
+apply (erule Cprod3_lemma1)
+done
+
+lemma Cprod3_lemma2: 
+"chain(Y::(nat=>'a::cpo)) ==> 
+  ((x::'b::cpo),lub(range Y)) = 
+  (lub(range(%i. fst(x,Y i))),lub(range(%i. snd(x, Y i))))"
+apply (rule_tac f1 = "Pair" in arg_cong [THEN cong])
+apply (rule sym)
+apply (simp (no_asm))
+apply (rule lub_const [THEN thelubI])
+apply (rule lub_equal)
+apply assumption
+apply (rule monofun_snd [THEN ch2ch_monofun])
+apply (rule monofun_pair2 [THEN ch2ch_monofun])
+apply assumption
+apply (rule allI)
+apply (simp (no_asm))
+done
+
+lemma contlub_pair2: "contlub(Pair(x))"
+apply (rule contlubI)
+apply (intro strip)
+apply (rule trans)
+apply (rule_tac [2] thelub_cprod [symmetric])
+apply (erule_tac [2] monofun_pair2 [THEN ch2ch_monofun])
+apply (erule Cprod3_lemma2)
+done
+
+lemma cont_pair1: "cont(Pair)"
+apply (rule monocontlub2cont)
+apply (rule monofun_pair1)
+apply (rule contlub_pair1)
+done
+
+lemma cont_pair2: "cont(Pair(x))"
+apply (rule monocontlub2cont)
+apply (rule monofun_pair2)
+apply (rule contlub_pair2)
+done
+
+lemma contlub_fst: "contlub(fst)"
+apply (rule contlubI)
+apply (intro strip)
+apply (subst lub_cprod [THEN thelubI])
+apply assumption
+apply (simp (no_asm))
+done
+
+lemma contlub_snd: "contlub(snd)"
+apply (rule contlubI)
+apply (intro strip)
+apply (subst lub_cprod [THEN thelubI])
+apply assumption
+apply (simp (no_asm))
+done
+
+lemma cont_fst: "cont(fst)"
+apply (rule monocontlub2cont)
+apply (rule monofun_fst)
+apply (rule contlub_fst)
+done
+
+lemma cont_snd: "cont(snd)"
+apply (rule monocontlub2cont)
+apply (rule monofun_snd)
+apply (rule contlub_snd)
+done
+
+(* 
+ -------------------------------------------------------------------------- 
+ more lemmas for Cprod3.thy 
+ 
+ -------------------------------------------------------------------------- 
+*)
+
+(* ------------------------------------------------------------------------ *)
+(* convert all lemmas to the continuous versions                            *)
+(* ------------------------------------------------------------------------ *)
+
+lemma beta_cfun_cprod: 
+        "(LAM x y.(x,y))$a$b = (a,b)"
+apply (subst beta_cfun)
+apply (simp (no_asm) add: cont_pair1 cont_pair2 cont2cont_CF1L)
+apply (subst beta_cfun)
+apply (rule cont_pair2)
+apply (rule refl)
+done
+
+lemma inject_cpair: 
+        "<a,b> = <aa,ba>  ==> a=aa & b=ba"
+apply (unfold cpair_def)
+apply (drule beta_cfun_cprod [THEN subst])
+apply (drule beta_cfun_cprod [THEN subst])
+apply (erule Pair_inject)
+apply fast
+done
+
+lemma inst_cprod_pcpo2: "UU = <UU,UU>"
+apply (unfold cpair_def)
+apply (rule sym)
+apply (rule trans)
+apply (rule beta_cfun_cprod)
+apply (rule sym)
+apply (rule inst_cprod_pcpo)
+done
+
+lemma defined_cpair_rev: 
+ "<a,b> = UU ==> a = UU & b = UU"
+apply (drule inst_cprod_pcpo2 [THEN subst])
+apply (erule inject_cpair)
+done
+
+lemma Exh_Cprod2:
+        "? a b. z=<a,b>"
+apply (unfold cpair_def)
+apply (rule PairE)
+apply (rule exI)
+apply (rule exI)
+apply (erule beta_cfun_cprod [THEN ssubst])
+done
+
+lemma cprodE:
+assumes prems: "!!x y. [| p = <x,y> |] ==> Q"
+shows "Q"
+apply (rule PairE)
+apply (rule prems)
+apply (unfold cpair_def)
+apply (erule beta_cfun_cprod [THEN ssubst])
+done
+
+lemma cfst2: 
+        "cfst$<x,y> = x"
+apply (unfold cfst_def cpair_def)
+apply (subst beta_cfun_cprod)
+apply (subst beta_cfun)
+apply (rule cont_fst)
+apply (simp (no_asm))
+done
+
+lemma csnd2: 
+        "csnd$<x,y> = y"
+apply (unfold csnd_def cpair_def)
+apply (subst beta_cfun_cprod)
+apply (subst beta_cfun)
+apply (rule cont_snd)
+apply (simp (no_asm))
+done
+
+lemma cfst_strict: "cfst$UU = UU"
+apply (simp add: inst_cprod_pcpo2 cfst2)
+done
+
+lemma csnd_strict: "csnd$UU = UU"
+apply (simp add: inst_cprod_pcpo2 csnd2)
+done
+
+lemma surjective_pairing_Cprod2: "<cfst$p , csnd$p> = p"
+apply (unfold cfst_def csnd_def cpair_def)
+apply (subst beta_cfun_cprod)
+apply (simplesubst beta_cfun)
+apply (rule cont_snd)
+apply (subst beta_cfun)
+apply (rule cont_fst)
+apply (rule surjective_pairing [symmetric])
+done
+
+lemma less_cprod5c: 
+ "<xa,ya> << <x,y> ==> xa<<x & ya << y"
+apply (unfold cfst_def csnd_def cpair_def)
+apply (rule less_cprod4c)
+apply (drule beta_cfun_cprod [THEN subst])
+apply (drule beta_cfun_cprod [THEN subst])
+apply assumption
+done
+
+lemma lub_cprod2: 
+"[|chain(S)|] ==> range(S) <<|  
+  <(lub(range(%i. cfst$(S i)))) , lub(range(%i. csnd$(S i)))>"
+apply (unfold cfst_def csnd_def cpair_def)
+apply (subst beta_cfun_cprod)
+apply (simplesubst beta_cfun [THEN ext])
+apply (rule cont_snd)
+apply (subst beta_cfun [THEN ext])
+apply (rule cont_fst)
+apply (rule lub_cprod)
+apply assumption
+done
+
+lemmas thelub_cprod2 = lub_cprod2 [THEN thelubI, standard]
+(*
+chain ?S1 ==>
+ lub (range ?S1) =
+ <lub (range (%i. cfst$(?S1 i))), lub (range (%i. csnd$(?S1 i)))>" 
+*)
+lemma csplit2: 
+        "csplit$f$<x,y> = f$x$y"
+apply (unfold csplit_def)
+apply (subst beta_cfun)
+apply (simp (no_asm))
+apply (simp (no_asm) add: cfst2 csnd2)
+done
+
+lemma csplit3: 
+  "csplit$cpair$z=z"
+apply (unfold csplit_def)
+apply (subst beta_cfun)
+apply (simp (no_asm))
+apply (simp (no_asm) add: surjective_pairing_Cprod2)
+done
+
+(* ------------------------------------------------------------------------ *)
+(* install simplifier for Cprod                                             *)
+(* ------------------------------------------------------------------------ *)
+
+declare cfst2 [simp] csnd2 [simp] csplit2 [simp]
+
+lemmas Cprod_rews = cfst2 csnd2 csplit2
+
+end