author | huffman |
Wed, 02 Mar 2005 23:28:17 +0100 | |
changeset 15565 | 2454493bd77b |
parent 14981 | e73f8140af78 |
child 15576 | efb95d0d01f7 |
permissions | -rw-r--r-- |
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(* Title: HOLCF/cont.thy |
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ID: $Id$ |
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Author: Franz Regensburger |
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License: GPL (GNU GENERAL PUBLIC LICENSE) |
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Results about continuity and monotonicity |
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*) |
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theory Cont = Fun3: |
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(* |
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Now we change the default class! Form now on all untyped typevariables are |
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of default class po |
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*) |
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defaultsort po |
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consts |
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monofun :: "('a => 'b) => bool" (* monotonicity *) |
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contlub :: "('a::cpo => 'b::cpo) => bool" (* first cont. def *) |
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cont :: "('a::cpo => 'b::cpo) => bool" (* secnd cont. def *) |
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The curried version of HOLCF is now just called HOLCF. The old
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defs |
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monofun: "monofun(f) == ! x y. x << y --> f(x) << f(y)" |
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contlub: "contlub(f) == ! Y. chain(Y) --> |
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f(lub(range(Y))) = lub(range(% i. f(Y(i))))" |
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cont: "cont(f) == ! Y. chain(Y) --> |
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range(% i. f(Y(i))) <<| f(lub(range(Y)))" |
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(* ------------------------------------------------------------------------ *) |
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(* the main purpose of cont.thy is to show: *) |
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(* monofun(f) & contlub(f) <==> cont(f) *) |
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(* ------------------------------------------------------------------------ *) |
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(* Title: HOLCF/Cont.ML |
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ID: $Id$ |
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Author: Franz Regensburger |
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License: GPL (GNU GENERAL PUBLIC LICENSE) |
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||
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Results about continuity and monotonicity |
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*) |
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||
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(* ------------------------------------------------------------------------ *) |
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(* access to definition *) |
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(* ------------------------------------------------------------------------ *) |
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lemma contlubI: |
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"! Y. chain(Y) --> f(lub(range(Y))) = lub(range(%i. f(Y(i))))==> |
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contlub(f)" |
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apply (unfold contlub) |
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apply assumption |
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done |
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lemma contlubE: |
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" contlub(f)==> |
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! Y. chain(Y) --> f(lub(range(Y))) = lub(range(%i. f(Y(i))))" |
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apply (unfold contlub) |
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apply assumption |
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done |
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lemma contI: |
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"! Y. chain(Y) --> range(% i. f(Y(i))) <<| f(lub(range(Y))) ==> cont(f)" |
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apply (unfold cont) |
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apply assumption |
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done |
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lemma contE: |
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"cont(f) ==> ! Y. chain(Y) --> range(% i. f(Y(i))) <<| f(lub(range(Y)))" |
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apply (unfold cont) |
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apply assumption |
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done |
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lemma monofunI: |
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"! x y. x << y --> f(x) << f(y) ==> monofun(f)" |
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apply (unfold monofun) |
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apply assumption |
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done |
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lemma monofunE: |
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"monofun(f) ==> ! x y. x << y --> f(x) << f(y)" |
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apply (unfold monofun) |
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apply assumption |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* the main purpose of cont.thy is to show: *) |
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(* monofun(f) & contlub(f) <==> cont(f) *) |
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(* ------------------------------------------------------------------------ *) |
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(* ------------------------------------------------------------------------ *) |
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(* monotone functions map chains to chains *) |
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(* ------------------------------------------------------------------------ *) |
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lemma ch2ch_monofun: |
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"[| monofun(f); chain(Y) |] ==> chain(%i. f(Y(i)))" |
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apply (rule chainI) |
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apply (erule monofunE [THEN spec, THEN spec, THEN mp]) |
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apply (erule chainE) |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* monotone functions map upper bound to upper bounds *) |
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(* ------------------------------------------------------------------------ *) |
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lemma ub2ub_monofun: |
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"[| monofun(f); range(Y) <| u|] ==> range(%i. f(Y(i))) <| f(u)" |
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apply (rule ub_rangeI) |
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apply (erule monofunE [THEN spec, THEN spec, THEN mp]) |
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apply (erule ub_rangeD) |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* left to right: monofun(f) & contlub(f) ==> cont(f) *) |
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(* ------------------------------------------------------------------------ *) |
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lemma monocontlub2cont: |
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"[|monofun(f);contlub(f)|] ==> cont(f)" |
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apply (unfold cont) |
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apply (intro strip) |
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apply (rule thelubE) |
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apply (erule ch2ch_monofun) |
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apply assumption |
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apply (erule contlubE [THEN spec, THEN mp, symmetric]) |
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apply assumption |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* first a lemma about binary chains *) |
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(* ------------------------------------------------------------------------ *) |
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lemma binchain_cont: "[| cont(f); x << y |] |
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==> range(%i::nat. f(if i = 0 then x else y)) <<| f(y)" |
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apply (rule subst) |
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prefer 2 apply (erule contE [THEN spec, THEN mp]) |
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apply (erule bin_chain) |
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apply (rule_tac y = "y" in arg_cong) |
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apply (erule lub_bin_chain [THEN thelubI]) |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* right to left: cont(f) ==> monofun(f) & contlub(f) *) |
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(* part1: cont(f) ==> monofun(f *) |
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(* ------------------------------------------------------------------------ *) |
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lemma cont2mono: "cont(f) ==> monofun(f)" |
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apply (unfold monofun) |
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apply (intro strip) |
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apply (drule binchain_cont [THEN is_ub_lub]) |
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apply (auto split add: split_if_asm) |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* right to left: cont(f) ==> monofun(f) & contlub(f) *) |
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(* part2: cont(f) ==> contlub(f) *) |
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(* ------------------------------------------------------------------------ *) |
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lemma cont2contlub: "cont(f) ==> contlub(f)" |
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apply (unfold contlub) |
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apply (intro strip) |
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apply (rule thelubI [symmetric]) |
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apply (erule contE [THEN spec, THEN mp]) |
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apply assumption |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* monotone functions map finite chains to finite chains *) |
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(* ------------------------------------------------------------------------ *) |
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lemma monofun_finch2finch: |
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"[| monofun f; finite_chain Y |] ==> finite_chain (%n. f (Y n))" |
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apply (unfold finite_chain_def) |
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apply (force elim!: ch2ch_monofun simp add: max_in_chain_def) |
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done |
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(* ------------------------------------------------------------------------ *) |
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(* The same holds for continuous functions *) |
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(* ------------------------------------------------------------------------ *) |
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lemmas cont_finch2finch = cont2mono [THEN monofun_finch2finch, standard] |
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(* [| cont ?f; finite_chain ?Y |] ==> finite_chain (%n. ?f (?Y n)) *) |
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(* ------------------------------------------------------------------------ *) |
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(* The following results are about a curried function that is monotone *) |
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(* in both arguments *) |
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(* ------------------------------------------------------------------------ *) |
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lemma ch2ch_MF2L: |
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"[|monofun(MF2); chain(F)|] ==> chain(%i. MF2 (F i) x)" |
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apply (erule ch2ch_monofun [THEN ch2ch_fun]) |
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apply assumption |
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done |
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lemma ch2ch_MF2R: |
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"[|monofun(MF2(f)); chain(Y)|] ==> chain(%i. MF2 f (Y i))" |
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apply (erule ch2ch_monofun) |
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apply assumption |
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done |
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lemma ch2ch_MF2LR: |
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"[|monofun(MF2); !f. monofun(MF2(f)); chain(F); chain(Y)|] ==> |
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chain(%i. MF2(F(i))(Y(i)))" |
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apply (rule chainI) |
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apply (rule trans_less) |
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apply (erule ch2ch_MF2L [THEN chainE]) |
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apply assumption |
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apply (rule monofunE [THEN spec, THEN spec, THEN mp], erule spec) |
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apply (erule chainE) |
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done |
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lemma ch2ch_lubMF2R: |
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"[|monofun(MF2::('a::po=>'b::po=>'c::cpo)); |
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!f. monofun(MF2(f)::('b::po=>'c::cpo)); |
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chain(F);chain(Y)|] ==> |
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chain(%j. lub(range(%i. MF2 (F j) (Y i))))" |
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apply (rule lub_mono [THEN chainI]) |
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apply (rule ch2ch_MF2R, erule spec) |
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apply assumption |
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apply (rule ch2ch_MF2R, erule spec) |
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apply assumption |
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apply (intro strip) |
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apply (rule chainE) |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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done |
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lemma ch2ch_lubMF2L: |
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"[|monofun(MF2::('a::po=>'b::po=>'c::cpo)); |
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!f. monofun(MF2(f)::('b::po=>'c::cpo)); |
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chain(F);chain(Y)|] ==> |
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chain(%i. lub(range(%j. MF2 (F j) (Y i))))" |
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apply (rule lub_mono [THEN chainI]) |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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apply (intro strip) |
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apply (rule chainE) |
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apply (rule ch2ch_MF2R, erule spec) |
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apply assumption |
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done |
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lemma lub_MF2_mono: |
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"[|monofun(MF2::('a::po=>'b::po=>'c::cpo)); |
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!f. monofun(MF2(f)::('b::po=>'c::cpo)); |
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chain(F)|] ==> |
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monofun(% x. lub(range(% j. MF2 (F j) (x))))" |
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apply (rule monofunI) |
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apply (intro strip) |
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apply (rule lub_mono) |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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apply (intro strip) |
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apply (rule monofunE [THEN spec, THEN spec, THEN mp], erule spec) |
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apply assumption |
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done |
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lemma ex_lubMF2: |
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"[|monofun(MF2::('a::po=>'b::po=>'c::cpo)); |
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!f. monofun(MF2(f)::('b::po=>'c::cpo)); |
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chain(F); chain(Y)|] ==> |
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lub(range(%j. lub(range(%i. MF2(F j) (Y i))))) = |
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lub(range(%i. lub(range(%j. MF2(F j) (Y i)))))" |
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apply (rule antisym_less) |
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apply (rule is_lub_thelub[OF _ ub_rangeI]) |
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apply (erule ch2ch_lubMF2R) |
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apply (assumption+) |
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apply (rule lub_mono) |
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apply (rule ch2ch_MF2R, erule spec) |
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apply assumption |
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apply (erule ch2ch_lubMF2L) |
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apply (assumption+) |
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apply (intro strip) |
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apply (rule is_ub_thelub) |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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apply (rule is_lub_thelub[OF _ ub_rangeI]) |
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apply (erule ch2ch_lubMF2L) |
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apply (assumption+) |
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apply (rule lub_mono) |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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apply (erule ch2ch_lubMF2R) |
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apply (assumption+) |
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apply (intro strip) |
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apply (rule is_ub_thelub) |
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apply (rule ch2ch_MF2R, erule spec) |
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apply assumption |
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done |
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lemma diag_lubMF2_1: |
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"[|monofun(MF2::('a::po=>'b::po=>'c::cpo)); |
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!f. monofun(MF2(f)::('b::po=>'c::cpo)); |
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chain(FY);chain(TY)|] ==> |
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lub(range(%i. lub(range(%j. MF2(FY(j))(TY(i)))))) = |
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lub(range(%i. MF2(FY(i))(TY(i))))" |
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apply (rule antisym_less) |
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apply (rule is_lub_thelub[OF _ ub_rangeI]) |
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apply (erule ch2ch_lubMF2L) |
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apply (assumption+) |
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apply (rule lub_mono3) |
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apply (erule ch2ch_MF2L) |
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apply (assumption+) |
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apply (erule ch2ch_MF2LR) |
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apply (assumption+) |
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apply (rule allI) |
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apply (rule_tac m = "i" and n = "ia" in nat_less_cases) |
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apply (rule_tac x = "ia" in exI) |
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apply (rule chain_mono) |
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apply (erule allE) |
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apply (erule ch2ch_MF2R) |
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apply (assumption+) |
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apply (erule ssubst) |
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apply (rule_tac x = "ia" in exI) |
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apply (rule refl_less) |
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apply (rule_tac x = "i" in exI) |
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apply (rule chain_mono) |
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apply (erule ch2ch_MF2L) |
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apply (assumption+) |
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apply (rule lub_mono) |
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apply (erule ch2ch_MF2LR) |
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apply (assumption+) |
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apply (erule ch2ch_lubMF2L) |
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apply (assumption+) |
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apply (intro strip) |
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apply (rule is_ub_thelub) |
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apply (erule ch2ch_MF2L) |
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apply assumption |
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done |
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lemma diag_lubMF2_2: |
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"[|monofun(MF2::('a::po=>'b::po=>'c::cpo)); |
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!f. monofun(MF2(f)::('b::po=>'c::cpo)); |
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chain(FY);chain(TY)|] ==> |
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lub(range(%j. lub(range(%i. MF2(FY(j))(TY(i)))))) = |
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lub(range(%i. MF2(FY(i))(TY(i))))" |
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apply (rule trans) |
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apply (rule ex_lubMF2) |
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apply (assumption+) |
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apply (erule diag_lubMF2_1) |
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apply (assumption+) |
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done |
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||
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(* ------------------------------------------------------------------------ *) |
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(* The following results are about a curried function that is continuous *) |
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(* in both arguments *) |
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(* ------------------------------------------------------------------------ *) |
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lemma contlub_CF2: |
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assumes prem1: "cont(CF2)" |
|
368 |
assumes prem2: "!f. cont(CF2(f))" |
|
369 |
assumes prem3: "chain(FY)" |
|
370 |
assumes prem4: "chain(TY)" |
|
371 |
shows "CF2(lub(range(FY)))(lub(range(TY))) = lub(range(%i. CF2(FY(i))(TY(i))))" |
|
372 |
apply (subst prem1 [THEN cont2contlub, THEN contlubE, THEN spec, THEN mp]) |
|
373 |
apply assumption |
|
374 |
apply (subst thelub_fun) |
|
375 |
apply (rule prem1 [THEN cont2mono [THEN ch2ch_monofun]]) |
|
376 |
apply assumption |
|
377 |
apply (rule trans) |
|
378 |
apply (rule prem2 [THEN spec, THEN cont2contlub, THEN contlubE, THEN spec, THEN mp, THEN ext, THEN arg_cong, THEN arg_cong]) |
|
379 |
apply (rule prem4) |
|
380 |
apply (rule diag_lubMF2_2) |
|
381 |
apply (auto simp add: cont2mono prems) |
|
382 |
done |
|
383 |
||
384 |
(* ------------------------------------------------------------------------ *) |
|
385 |
(* The following results are about application for functions in 'a=>'b *) |
|
386 |
(* ------------------------------------------------------------------------ *) |
|
387 |
||
388 |
lemma monofun_fun_fun: "f1 << f2 ==> f1(x) << f2(x)" |
|
389 |
apply (erule less_fun [THEN iffD1, THEN spec]) |
|
390 |
done |
|
391 |
||
392 |
lemma monofun_fun_arg: "[|monofun(f); x1 << x2|] ==> f(x1) << f(x2)" |
|
393 |
apply (erule monofunE [THEN spec, THEN spec, THEN mp]) |
|
394 |
apply assumption |
|
395 |
done |
|
396 |
||
397 |
lemma monofun_fun: "[|monofun(f1); monofun(f2); f1 << f2; x1 << x2|] ==> f1(x1) << f2(x2)" |
|
398 |
apply (rule trans_less) |
|
399 |
apply (erule monofun_fun_arg) |
|
400 |
apply assumption |
|
401 |
apply (erule monofun_fun_fun) |
|
402 |
done |
|
403 |
||
404 |
||
405 |
(* ------------------------------------------------------------------------ *) |
|
406 |
(* The following results are about the propagation of monotonicity and *) |
|
407 |
(* continuity *) |
|
408 |
(* ------------------------------------------------------------------------ *) |
|
409 |
||
410 |
lemma mono2mono_MF1L: "[|monofun(c1)|] ==> monofun(%x. c1 x y)" |
|
411 |
apply (rule monofunI) |
|
412 |
apply (intro strip) |
|
413 |
apply (erule monofun_fun_arg [THEN monofun_fun_fun]) |
|
414 |
apply assumption |
|
415 |
done |
|
416 |
||
417 |
lemma cont2cont_CF1L: "[|cont(c1)|] ==> cont(%x. c1 x y)" |
|
418 |
apply (rule monocontlub2cont) |
|
419 |
apply (erule cont2mono [THEN mono2mono_MF1L]) |
|
420 |
apply (rule contlubI) |
|
421 |
apply (intro strip) |
|
422 |
apply (frule asm_rl) |
|
423 |
apply (erule cont2contlub [THEN contlubE, THEN spec, THEN mp, THEN ssubst]) |
|
424 |
apply assumption |
|
425 |
apply (subst thelub_fun) |
|
426 |
apply (rule ch2ch_monofun) |
|
427 |
apply (erule cont2mono) |
|
428 |
apply assumption |
|
429 |
apply (rule refl) |
|
430 |
done |
|
431 |
||
432 |
(********* Note "(%x.%y.c1 x y) = c1" ***********) |
|
433 |
||
434 |
lemma mono2mono_MF1L_rev: "!y. monofun(%x. c1 x y) ==> monofun(c1)" |
|
435 |
apply (rule monofunI) |
|
436 |
apply (intro strip) |
|
437 |
apply (rule less_fun [THEN iffD2]) |
|
438 |
apply (blast dest: monofunE) |
|
439 |
done |
|
440 |
||
441 |
lemma cont2cont_CF1L_rev: "!y. cont(%x. c1 x y) ==> cont(c1)" |
|
442 |
apply (rule monocontlub2cont) |
|
443 |
apply (rule cont2mono [THEN allI, THEN mono2mono_MF1L_rev]) |
|
444 |
apply (erule spec) |
|
445 |
apply (rule contlubI) |
|
446 |
apply (intro strip) |
|
447 |
apply (rule ext) |
|
448 |
apply (subst thelub_fun) |
|
449 |
apply (rule cont2mono [THEN allI, THEN mono2mono_MF1L_rev, THEN ch2ch_monofun]) |
|
450 |
apply (erule spec) |
|
451 |
apply assumption |
|
452 |
apply (blast dest: cont2contlub [THEN contlubE]) |
|
453 |
done |
|
454 |
||
455 |
(* ------------------------------------------------------------------------ *) |
|
456 |
(* What D.A.Schmidt calls continuity of abstraction *) |
|
457 |
(* never used here *) |
|
458 |
(* ------------------------------------------------------------------------ *) |
|
459 |
||
460 |
lemma contlub_abstraction: |
|
461 |
"[|chain(Y::nat=>'a);!y. cont(%x.(c::'a::cpo=>'b::cpo=>'c::cpo) x y)|] ==> |
|
462 |
(%y. lub(range(%i. c (Y i) y))) = (lub(range(%i.%y. c (Y i) y)))" |
|
463 |
apply (rule trans) |
|
464 |
prefer 2 apply (rule cont2contlub [THEN contlubE, THEN spec, THEN mp]) |
|
465 |
prefer 2 apply (assumption) |
|
466 |
apply (erule cont2cont_CF1L_rev) |
|
467 |
apply (rule ext) |
|
468 |
apply (rule cont2contlub [THEN contlubE, THEN spec, THEN mp, symmetric]) |
|
469 |
apply (erule spec) |
|
470 |
apply assumption |
|
471 |
done |
|
472 |
||
473 |
lemma mono2mono_app: "[|monofun(ft);!x. monofun(ft(x));monofun(tt)|] ==> |
|
474 |
monofun(%x.(ft(x))(tt(x)))" |
|
475 |
apply (rule monofunI) |
|
476 |
apply (intro strip) |
|
477 |
apply (rule_tac ?f1.0 = "ft(x)" and ?f2.0 = "ft(y)" in monofun_fun) |
|
478 |
apply (erule spec) |
|
479 |
apply (erule spec) |
|
480 |
apply (erule monofunE [THEN spec, THEN spec, THEN mp]) |
|
481 |
apply assumption |
|
482 |
apply (erule monofunE [THEN spec, THEN spec, THEN mp]) |
|
483 |
apply assumption |
|
484 |
done |
|
485 |
||
486 |
||
487 |
lemma cont2contlub_app: "[|cont(ft);!x. cont(ft(x));cont(tt)|] ==> contlub(%x.(ft(x))(tt(x)))" |
|
488 |
apply (rule contlubI) |
|
489 |
apply (intro strip) |
|
490 |
apply (rule_tac f3 = "tt" in contlubE [THEN spec, THEN mp, THEN ssubst]) |
|
491 |
apply (erule cont2contlub) |
|
492 |
apply assumption |
|
493 |
apply (rule contlub_CF2) |
|
494 |
apply (assumption+) |
|
495 |
apply (erule cont2mono [THEN ch2ch_monofun]) |
|
496 |
apply assumption |
|
497 |
done |
|
498 |
||
499 |
||
500 |
lemma cont2cont_app: "[|cont(ft); !x. cont(ft(x)); cont(tt)|] ==> cont(%x.(ft(x))(tt(x)))" |
|
501 |
apply (blast intro: monocontlub2cont mono2mono_app cont2mono cont2contlub_app) |
|
502 |
done |
|
503 |
||
504 |
||
505 |
lemmas cont2cont_app2 = cont2cont_app[OF _ allI] |
|
506 |
(* [| cont ?ft; !!x. cont (?ft x); cont ?tt |] ==> *) |
|
507 |
(* cont (%x. ?ft x (?tt x)) *) |
|
508 |
||
509 |
||
510 |
(* ------------------------------------------------------------------------ *) |
|
511 |
(* The identity function is continuous *) |
|
512 |
(* ------------------------------------------------------------------------ *) |
|
513 |
||
514 |
lemma cont_id: "cont(% x. x)" |
|
515 |
apply (rule contI) |
|
516 |
apply (intro strip) |
|
517 |
apply (erule thelubE) |
|
518 |
apply (rule refl) |
|
519 |
done |
|
520 |
||
521 |
(* ------------------------------------------------------------------------ *) |
|
522 |
(* constant functions are continuous *) |
|
523 |
(* ------------------------------------------------------------------------ *) |
|
524 |
||
525 |
lemma cont_const: "cont(%x. c)" |
|
526 |
apply (unfold cont) |
|
527 |
apply (intro strip) |
|
528 |
apply (blast intro: is_lubI ub_rangeI dest: ub_rangeD) |
|
529 |
done |
|
530 |
||
531 |
||
532 |
lemma cont2cont_app3: "[|cont(f); cont(t) |] ==> cont(%x. f(t(x)))" |
|
533 |
apply (best intro: cont2cont_app2 cont_const) |
|
534 |
done |
|
535 |
||
536 |
(* ------------------------------------------------------------------------ *) |
|
537 |
(* A non-emptyness result for Cfun *) |
|
538 |
(* ------------------------------------------------------------------------ *) |
|
539 |
||
540 |
lemma CfunI: "?x:Collect cont" |
|
541 |
apply (rule CollectI) |
|
542 |
apply (rule cont_const) |
|
543 |
done |
|
544 |
||
545 |
(* ------------------------------------------------------------------------ *) |
|
546 |
(* some properties of flat *) |
|
547 |
(* ------------------------------------------------------------------------ *) |
|
548 |
||
549 |
lemma flatdom2monofun: "f UU = UU ==> monofun (f::'a::flat=>'b::pcpo)" |
|
550 |
||
551 |
apply (unfold monofun) |
|
552 |
apply (intro strip) |
|
553 |
apply (drule ax_flat [THEN spec, THEN spec, THEN mp]) |
|
554 |
apply auto |
|
555 |
done |
|
556 |
||
557 |
declare range_composition [simp del] |
|
558 |
lemma chfindom_monofun2cont: "monofun f ==> cont(f::'a::chfin=>'b::pcpo)" |
|
559 |
apply (rule monocontlub2cont) |
|
560 |
apply assumption |
|
561 |
apply (rule contlubI) |
|
562 |
apply (intro strip) |
|
563 |
apply (frule chfin2finch) |
|
564 |
apply (rule antisym_less) |
|
565 |
apply (clarsimp simp add: finite_chain_def maxinch_is_thelub) |
|
566 |
apply (rule is_ub_thelub) |
|
567 |
apply (erule ch2ch_monofun) |
|
568 |
apply assumption |
|
569 |
apply (drule monofun_finch2finch[COMP swap_prems_rl]) |
|
570 |
apply assumption |
|
571 |
apply (simp add: finite_chain_def) |
|
572 |
apply (erule conjE) |
|
573 |
apply (erule exE) |
|
574 |
apply (simp add: maxinch_is_thelub) |
|
575 |
apply (erule monofunE [THEN spec, THEN spec, THEN mp]) |
|
576 |
apply (erule is_ub_thelub) |
|
577 |
done |
|
578 |
||
579 |
lemmas flatdom_strict2cont = flatdom2monofun [THEN chfindom_monofun2cont, standard] |
|
580 |
(* f UU = UU ==> cont (f::'a=>'b::pcpo)" *) |
|
581 |
||
243
c22b85994e17
Franz Regensburger's Higher-Order Logic of Computable Functions embedding LCF
nipkow
parents:
diff
changeset
|
582 |
end |