--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOLCF/cont.ML Wed Jan 19 17:35:01 1994 +0100
@@ -0,0 +1,670 @@
+(* Title: HOLCF/cont.ML
+ ID: $Id$
+ Author: Franz Regensburger
+ Copyright 1993 Technische Universitaet Muenchen
+
+Lemmas for cont.thy
+*)
+
+open Cont;
+
+(* ------------------------------------------------------------------------ *)
+(* access to definition *)
+(* ------------------------------------------------------------------------ *)
+
+val contlubI = prove_goalw Cont.thy [contlub]
+ "! Y. is_chain(Y) --> f(lub(range(Y))) = lub(range(%i. f(Y(i))))==>\
+\ contlub(f)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (atac 1)
+ ]);
+
+val contlubE = prove_goalw Cont.thy [contlub]
+ " contlub(f)==>\
+\ ! Y. is_chain(Y) --> f(lub(range(Y))) = lub(range(%i. f(Y(i))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (atac 1)
+ ]);
+
+
+val contXI = prove_goalw Cont.thy [contX]
+ "! Y. is_chain(Y) --> range(% i.f(Y(i))) <<| f(lub(range(Y))) ==> contX(f)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (atac 1)
+ ]);
+
+val contXE = prove_goalw Cont.thy [contX]
+ "contX(f) ==> ! Y. is_chain(Y) --> range(% i.f(Y(i))) <<| f(lub(range(Y)))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (atac 1)
+ ]);
+
+
+val monofunI = prove_goalw Cont.thy [monofun]
+ "! x y. x << y --> f(x) << f(y) ==> monofun(f)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (atac 1)
+ ]);
+
+val monofunE = prove_goalw Cont.thy [monofun]
+ "monofun(f) ==> ! x y. x << y --> f(x) << f(y)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (atac 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* the main purpose of cont.thy is to show: *)
+(* monofun(f) & contlub(f) <==> contX(f) *)
+(* ------------------------------------------------------------------------ *)
+
+(* ------------------------------------------------------------------------ *)
+(* monotone functions map chains to chains *)
+(* ------------------------------------------------------------------------ *)
+
+val ch2ch_monofun= prove_goal Cont.thy
+ "[| monofun(f); is_chain(Y) |] ==> is_chain(%i. f(Y(i)))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac is_chainI 1),
+ (rtac allI 1),
+ (etac (monofunE RS spec RS spec RS mp) 1),
+ (etac (is_chainE RS spec) 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* monotone functions map upper bound to upper bounds *)
+(* ------------------------------------------------------------------------ *)
+
+val ub2ub_monofun = prove_goal Cont.thy
+ "[| monofun(f); range(Y) <| u|] ==> range(%i.f(Y(i))) <| f(u)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac ub_rangeI 1),
+ (rtac allI 1),
+ (etac (monofunE RS spec RS spec RS mp) 1),
+ (etac (ub_rangeE RS spec) 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* left to right: monofun(f) & contlub(f) ==> contX(f) *)
+(* ------------------------------------------------------------------------ *)
+
+val monocontlub2contX = prove_goalw Cont.thy [contX]
+ "[|monofun(f);contlub(f)|] ==> contX(f)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (strip_tac 1),
+ (rtac thelubE 1),
+ (etac ch2ch_monofun 1),
+ (atac 1),
+ (etac (contlubE RS spec RS mp RS sym) 1),
+ (atac 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* first a lemma about binary chains *)
+(* ------------------------------------------------------------------------ *)
+
+val binchain_contX = prove_goal Cont.thy
+"[| contX(f); x << y |] ==> range(%i. f(if(i = 0,x,y))) <<| f(y)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac subst 1),
+ (etac (contXE RS spec RS mp) 2),
+ (etac bin_chain 2),
+ (res_inst_tac [("y","y")] arg_cong 1),
+ (etac (lub_bin_chain RS thelubI) 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* right to left: contX(f) ==> monofun(f) & contlub(f) *)
+(* part1: contX(f) ==> monofun(f *)
+(* ------------------------------------------------------------------------ *)
+
+val contX2mono = prove_goalw Cont.thy [monofun]
+ "contX(f) ==> monofun(f)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (strip_tac 1),
+ (res_inst_tac [("s","if(0 = 0,x,y)")] subst 1),
+ (rtac (binchain_contX RS is_ub_lub) 2),
+ (atac 2),
+ (atac 2),
+ (simp_tac nat_ss 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* right to left: contX(f) ==> monofun(f) & contlub(f) *)
+(* part2: contX(f) ==> contlub(f) *)
+(* ------------------------------------------------------------------------ *)
+
+val contX2contlub = prove_goalw Cont.thy [contlub]
+ "contX(f) ==> contlub(f)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (strip_tac 1),
+ (rtac (thelubI RS sym) 1),
+ (etac (contXE RS spec RS mp) 1),
+ (atac 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* The following results are about a curried function that is monotone *)
+(* in both arguments *)
+(* ------------------------------------------------------------------------ *)
+
+val ch2ch_MF2L = prove_goal Cont.thy
+"[|monofun(MF2::('a::po=>'b::po=>'c::po));\
+\ is_chain(F)|] ==> is_chain(%i. MF2(F(i),x))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (etac (ch2ch_monofun RS ch2ch_fun) 1),
+ (atac 1)
+ ]);
+
+
+val ch2ch_MF2R = prove_goal Cont.thy "[|monofun(MF2(f)::('b::po=>'c::po));\
+\ is_chain(Y)|] ==> is_chain(%i. MF2(f,Y(i)))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (etac ch2ch_monofun 1),
+ (atac 1)
+ ]);
+
+val ch2ch_MF2LR = prove_goal Cont.thy
+"[|monofun(MF2::('a::po=>'b::po=>'c::pcpo));\
+\ !f.monofun(MF2(f)::('b::po=>'c::pcpo));\
+\ is_chain(F); is_chain(Y)|] ==> \
+\ is_chain(%i. MF2(F(i))(Y(i)))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac is_chainI 1),
+ (strip_tac 1 ),
+ (rtac trans_less 1),
+ (etac (ch2ch_MF2L RS is_chainE RS spec) 1),
+ (atac 1),
+ ((rtac (monofunE RS spec RS spec RS mp) 1) THEN (etac spec 1)),
+ (etac (is_chainE RS spec) 1)
+ ]);
+
+val ch2ch_lubMF2R = prove_goal Cont.thy
+"[|monofun(MF2::('a::po=>'b::po=>'c::pcpo));\
+\ !f.monofun(MF2(f)::('b::po=>'c::pcpo));\
+\ is_chain(F);is_chain(Y)|] ==> \
+\ is_chain(%j. lub(range(%i. MF2(F(j),Y(i)))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac (lub_mono RS allI RS is_chainI) 1),
+ ((rtac ch2ch_MF2R 1) THEN (etac spec 1)),
+ (atac 1),
+ ((rtac ch2ch_MF2R 1) THEN (etac spec 1)),
+ (atac 1),
+ (strip_tac 1),
+ (rtac (is_chainE RS spec) 1),
+ (etac ch2ch_MF2L 1),
+ (atac 1)
+ ]);
+
+
+val ch2ch_lubMF2L = prove_goal Cont.thy
+"[|monofun(MF2::('a::po=>'b::po=>'c::pcpo));\
+\ !f.monofun(MF2(f)::('b::po=>'c::pcpo));\
+\ is_chain(F);is_chain(Y)|] ==> \
+\ is_chain(%i. lub(range(%j. MF2(F(j),Y(i)))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac (lub_mono RS allI RS is_chainI) 1),
+ (etac ch2ch_MF2L 1),
+ (atac 1),
+ (etac ch2ch_MF2L 1),
+ (atac 1),
+ (strip_tac 1),
+ (rtac (is_chainE RS spec) 1),
+ ((rtac ch2ch_MF2R 1) THEN (etac spec 1)),
+ (atac 1)
+ ]);
+
+
+val lub_MF2_mono = prove_goal Cont.thy
+"[|monofun(MF2::('a::po=>'b::po=>'c::pcpo));\
+\ !f.monofun(MF2(f)::('b::po=>'c::pcpo));\
+\ is_chain(F)|] ==> \
+\ monofun(% x.lub(range(% j.MF2(F(j),x))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac monofunI 1),
+ (strip_tac 1),
+ (rtac lub_mono 1),
+ (etac ch2ch_MF2L 1),
+ (atac 1),
+ (etac ch2ch_MF2L 1),
+ (atac 1),
+ (strip_tac 1),
+ ((rtac (monofunE RS spec RS spec RS mp) 1) THEN (etac spec 1)),
+ (atac 1)
+ ]);
+
+
+val ex_lubMF2 = prove_goal Cont.thy
+"[|monofun(MF2::('a::po=>'b::po=>'c::pcpo));\
+\ !f.monofun(MF2(f)::('b::po=>'c::pcpo));\
+\ is_chain(F); is_chain(Y)|] ==> \
+\ lub(range(%j. lub(range(%i. MF2(F(j),Y(i)))))) =\
+\ lub(range(%i. lub(range(%j. MF2(F(j),Y(i))))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac antisym_less 1),
+ (rtac is_lub_thelub 1),
+ (etac ch2ch_lubMF2R 1),
+ (atac 1),(atac 1),(atac 1),
+ (rtac ub_rangeI 1),
+ (strip_tac 1),
+ (rtac lub_mono 1),
+ ((rtac ch2ch_MF2R 1) THEN (etac spec 1)),
+ (atac 1),
+ (etac ch2ch_lubMF2L 1),
+ (atac 1),(atac 1),(atac 1),
+ (strip_tac 1),
+ (rtac is_ub_thelub 1),
+ (etac ch2ch_MF2L 1),(atac 1),
+ (rtac is_lub_thelub 1),
+ (etac ch2ch_lubMF2L 1),
+ (atac 1),(atac 1),(atac 1),
+ (rtac ub_rangeI 1),
+ (strip_tac 1),
+ (rtac lub_mono 1),
+ (etac ch2ch_MF2L 1),(atac 1),
+ (etac ch2ch_lubMF2R 1),
+ (atac 1),(atac 1),(atac 1),
+ (strip_tac 1),
+ (rtac is_ub_thelub 1),
+ ((rtac ch2ch_MF2R 1) THEN (etac spec 1)),
+ (atac 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* The following results are about a curried function that is continuous *)
+(* in both arguments *)
+(* ------------------------------------------------------------------------ *)
+
+val diag_lubCF2_1 = prove_goal Cont.thy
+"[|contX(CF2);!f.contX(CF2(f));is_chain(FY);is_chain(TY)|] ==>\
+\ lub(range(%i. lub(range(%j. CF2(FY(j))(TY(i)))))) =\
+\ lub(range(%i. CF2(FY(i))(TY(i))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac antisym_less 1),
+ (rtac is_lub_thelub 1),
+ (rtac ch2ch_lubMF2L 1),
+ (rtac contX2mono 1),
+ (atac 1),
+ (rtac allI 1),
+ (rtac contX2mono 1),
+ (etac spec 1),
+ (atac 1),
+ (atac 1),
+ (rtac ub_rangeI 1),
+ (strip_tac 1 ),
+ (rtac is_lub_thelub 1),
+ ((rtac ch2ch_MF2L 1) THEN (rtac contX2mono 1) THEN (atac 1)),
+ (atac 1),
+ (rtac ub_rangeI 1),
+ (strip_tac 1 ),
+ (res_inst_tac [("m","i"),("n","ia")] nat_less_cases 1),
+ (rtac trans_less 1),
+ (rtac is_ub_thelub 2),
+ (rtac (chain_mono RS mp) 1),
+ ((rtac ch2ch_MF2R 1) THEN (rtac contX2mono 1) THEN (etac spec 1)),
+ (atac 1),
+ (atac 1),
+ ((rtac ch2ch_MF2LR 1) THEN (etac contX2mono 1)),
+ (rtac allI 1),
+ ((rtac contX2mono 1) THEN (etac spec 1)),
+ (atac 1),
+ (atac 1),
+ (hyp_subst_tac 1),
+ (rtac is_ub_thelub 1),
+ ((rtac ch2ch_MF2LR 1) THEN (etac contX2mono 1)),
+ (rtac allI 1),
+ ((rtac contX2mono 1) THEN (etac spec 1)),
+ (atac 1),
+ (atac 1),
+ (rtac trans_less 1),
+ (rtac is_ub_thelub 2),
+ (res_inst_tac [("x1","ia")] (chain_mono RS mp) 1),
+ ((rtac ch2ch_MF2L 1) THEN (etac contX2mono 1)),
+ (atac 1),
+ (atac 1),
+ ((rtac ch2ch_MF2LR 1) THEN (etac contX2mono 1)),
+ (rtac allI 1),
+ ((rtac contX2mono 1) THEN (etac spec 1)),
+ (atac 1),
+ (atac 1),
+ (rtac lub_mono 1),
+ ((rtac ch2ch_MF2LR 1) THEN (etac contX2mono 1)),
+ (rtac allI 1),
+ ((rtac contX2mono 1) THEN (etac spec 1)),
+ (atac 1),
+ (atac 1),
+ (rtac ch2ch_lubMF2L 1),
+ (rtac contX2mono 1),
+ (atac 1),
+ (rtac allI 1),
+ ((rtac contX2mono 1) THEN (etac spec 1)),
+ (atac 1),
+ (atac 1),
+ (strip_tac 1 ),
+ (rtac is_ub_thelub 1),
+ ((rtac ch2ch_MF2L 1) THEN (etac contX2mono 1)),
+ (atac 1)
+ ]);
+
+
+val diag_lubCF2_2 = prove_goal Cont.thy
+"[|contX(CF2);!f.contX(CF2(f));is_chain(FY);is_chain(TY)|] ==>\
+\ lub(range(%j. lub(range(%i. CF2(FY(j))(TY(i)))))) =\
+\ lub(range(%i. CF2(FY(i))(TY(i))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac trans 1),
+ (rtac ex_lubMF2 1),
+ (rtac ((hd prems) RS contX2mono) 1),
+ (rtac allI 1),
+ (rtac (((hd (tl prems)) RS spec RS contX2mono)) 1),
+ (atac 1),
+ (atac 1),
+ (rtac diag_lubCF2_1 1),
+ (atac 1),
+ (atac 1),
+ (atac 1),
+ (atac 1)
+ ]);
+
+
+val contlub_CF2 = prove_goal Cont.thy
+"[|contX(CF2);!f.contX(CF2(f));is_chain(FY);is_chain(TY)|] ==>\
+\ CF2(lub(range(FY)))(lub(range(TY))) = lub(range(%i.CF2(FY(i))(TY(i))))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac ((hd prems) RS contX2contlub RS contlubE RS
+ spec RS mp RS ssubst) 1),
+ (atac 1),
+ (rtac (thelub_fun RS ssubst) 1),
+ (rtac ((hd prems) RS contX2mono RS ch2ch_monofun) 1),
+ (atac 1),
+ (rtac trans 1),
+ (rtac (((hd (tl prems)) RS spec RS contX2contlub) RS
+ contlubE RS spec RS mp RS ext RS arg_cong RS arg_cong) 1),
+ (atac 1),
+ (rtac diag_lubCF2_2 1),
+ (atac 1),
+ (atac 1),
+ (atac 1),
+ (atac 1)
+ ]);
+
+(* ------------------------------------------------------------------------ *)
+(* The following results are about application for functions in 'a=>'b *)
+(* ------------------------------------------------------------------------ *)
+
+val monofun_fun_fun = prove_goal Cont.thy
+ "f1 << f2 ==> f1(x) << f2(x)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (etac (less_fun RS iffD1 RS spec) 1)
+ ]);
+
+val monofun_fun_arg = prove_goal Cont.thy
+ "[|monofun(f); x1 << x2|] ==> f(x1) << f(x2)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (etac (monofunE RS spec RS spec RS mp) 1),
+ (atac 1)
+ ]);
+
+val monofun_fun = prove_goal Cont.thy
+"[|monofun(f1); monofun(f2); f1 << f2; x1 << x2|] ==> f1(x1) << f2(x2)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac trans_less 1),
+ (etac monofun_fun_arg 1),
+ (atac 1),
+ (etac monofun_fun_fun 1)
+ ]);
+
+
+(* ------------------------------------------------------------------------ *)
+(* The following results are about the propagation of monotonicity and *)
+(* continuity *)
+(* ------------------------------------------------------------------------ *)
+
+val mono2mono_MF1L = prove_goal Cont.thy
+ "[|monofun(c1)|] ==> monofun(%x. c1(x,y))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac monofunI 1),
+ (strip_tac 1),
+ (etac (monofun_fun_arg RS monofun_fun_fun) 1),
+ (atac 1)
+ ]);
+
+val contX2contX_CF1L = prove_goal Cont.thy
+ "[|contX(c1)|] ==> contX(%x. c1(x,y))"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac monocontlub2contX 1),
+ (etac (contX2mono RS mono2mono_MF1L) 1),
+ (rtac contlubI 1),
+ (strip_tac 1),
+ (rtac ((hd prems) RS contX2contlub RS
+ contlubE RS spec RS mp RS ssubst) 1),
+ (atac 1),
+ (rtac (thelub_fun RS ssubst) 1),
+ (rtac ch2ch_monofun 1),
+ (etac contX2mono 1),
+ (atac 1),
+ (rtac refl 1)
+ ]);
+
+(********* Note "(%x.%y.c1(x,y)) = c1" ***********)
+
+val mono2mono_MF1L_rev = prove_goal Cont.thy
+ "!y.monofun(%x.c1(x,y)) ==> monofun(c1)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac monofunI 1),
+ (strip_tac 1),
+ (rtac (less_fun RS iffD2) 1),
+ (strip_tac 1),
+ (rtac ((hd prems) RS spec RS monofunE RS spec RS spec RS mp) 1),
+ (atac 1)
+ ]);
+
+val contX2contX_CF1L_rev = prove_goal Cont.thy
+ "!y.contX(%x.c1(x,y)) ==> contX(c1)"
+(fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac monocontlub2contX 1),
+ (rtac (contX2mono RS allI RS mono2mono_MF1L_rev ) 1),
+ (etac spec 1),
+ (rtac contlubI 1),
+ (strip_tac 1),
+ (rtac ext 1),
+ (rtac (thelub_fun RS ssubst) 1),
+ (rtac (contX2mono RS allI RS mono2mono_MF1L_rev RS ch2ch_monofun) 1),
+ (etac spec 1),
+ (atac 1),
+ (rtac
+ ((hd prems) RS spec RS contX2contlub RS contlubE RS spec RS mp) 1),
+ (atac 1)
+ ]);
+
+
+(* ------------------------------------------------------------------------ *)
+(* What D.A.Schmidt calls continuity of abstraction *)
+(* never used here *)
+(* ------------------------------------------------------------------------ *)
+
+val contlub_abstraction = prove_goal Cont.thy
+"[|is_chain(Y::nat=>'a);!y.contX(%x.(c::'a=>'b=>'c)(x,y))|] ==>\
+\ (%y.lub(range(%i.c(Y(i),y)))) = (lub(range(%i.%y.c(Y(i),y))))"
+ (fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac trans 1),
+ (rtac (contX2contlub RS contlubE RS spec RS mp) 2),
+ (atac 3),
+ (etac contX2contX_CF1L_rev 2),
+ (rtac ext 1),
+ (rtac (contX2contlub RS contlubE RS spec RS mp RS sym) 1),
+ (etac spec 1),
+ (atac 1)
+ ]);
+
+
+val mono2mono_app = prove_goal Cont.thy
+"[|monofun(ft);!x.monofun(ft(x));monofun(tt)|] ==>\
+\ monofun(%x.(ft(x))(tt(x)))"
+ (fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac monofunI 1),
+ (strip_tac 1),
+ (res_inst_tac [("f1.0","ft(x)"),("f2.0","ft(y)")] monofun_fun 1),
+ (etac spec 1),
+ (etac spec 1),
+ (etac (monofunE RS spec RS spec RS mp) 1),
+ (atac 1),
+ (etac (monofunE RS spec RS spec RS mp) 1),
+ (atac 1)
+ ]);
+
+val contX2contlub_app = prove_goal Cont.thy
+"[|contX(ft);!x.contX(ft(x));contX(tt)|] ==>\
+\ contlub(%x.(ft(x))(tt(x)))"
+ (fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac contlubI 1),
+ (strip_tac 1),
+ (res_inst_tac [("f3","tt")] (contlubE RS spec RS mp RS ssubst) 1),
+ (rtac contX2contlub 1),
+ (resolve_tac prems 1),
+ (atac 1),
+ (rtac contlub_CF2 1),
+ (resolve_tac prems 1),
+ (resolve_tac prems 1),
+ (atac 1),
+ (rtac (contX2mono RS ch2ch_monofun) 1),
+ (resolve_tac prems 1),
+ (atac 1)
+ ]);
+
+
+val contX2contX_app = prove_goal Cont.thy
+"[|contX(ft);!x.contX(ft(x));contX(tt)|] ==>\
+\ contX(%x.(ft(x))(tt(x)))"
+ (fn prems =>
+ [
+ (rtac monocontlub2contX 1),
+ (rtac mono2mono_app 1),
+ (rtac contX2mono 1),
+ (resolve_tac prems 1),
+ (strip_tac 1),
+ (rtac contX2mono 1),
+ (cut_facts_tac prems 1),
+ (etac spec 1),
+ (rtac contX2mono 1),
+ (resolve_tac prems 1),
+ (rtac contX2contlub_app 1),
+ (resolve_tac prems 1),
+ (resolve_tac prems 1),
+ (resolve_tac prems 1)
+ ]);
+
+
+val contX2contX_app2 = (allI RSN (2,contX2contX_app));
+(* [| contX(?ft); !!x. contX(?ft(x)); contX(?tt) |] ==> *)
+(* contX(%x. ?ft(x,?tt(x))) *)
+
+
+(* ------------------------------------------------------------------------ *)
+(* The identity function is continuous *)
+(* ------------------------------------------------------------------------ *)
+
+val contX_id = prove_goal Cont.thy "contX(% x.x)"
+ (fn prems =>
+ [
+ (rtac contXI 1),
+ (strip_tac 1),
+ (etac thelubE 1),
+ (rtac refl 1)
+ ]);
+
+
+
+(* ------------------------------------------------------------------------ *)
+(* constant functions are continuous *)
+(* ------------------------------------------------------------------------ *)
+
+val contX_const = prove_goalw Cont.thy [contX] "contX(%x.c)"
+ (fn prems =>
+ [
+ (strip_tac 1),
+ (rtac is_lubI 1),
+ (rtac conjI 1),
+ (rtac ub_rangeI 1),
+ (strip_tac 1),
+ (rtac refl_less 1),
+ (strip_tac 1),
+ (dtac ub_rangeE 1),
+ (etac spec 1)
+ ]);
+
+
+val contX2contX_app3 = prove_goal Cont.thy
+ "[|contX(f);contX(t) |] ==> contX(%x. f(t(x)))"
+ (fn prems =>
+ [
+ (cut_facts_tac prems 1),
+ (rtac contX2contX_app2 1),
+ (rtac contX_const 1),
+ (atac 1),
+ (atac 1)
+ ]);
+