removed proof about Ifix, which no longer exists

--- a/src/HOLCF/ex/ROOT.ML	Thu Nov 03 00:16:09 2005 +0100
+++ b/src/HOLCF/ex/ROOT.ML	Thu Nov 03 00:31:32 2005 +0100
@@ -11,5 +11,4 @@
 time_use_thy "Fix2";
 time_use_thy "Hoare";
 time_use_thy "Loop";
-time_use "loeckx.ML";
 time_use_thy "Fixrec_ex";

--- a/src/HOLCF/ex/loeckx.ML	Thu Nov 03 00:16:09 2005 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,102 +0,0 @@
-(* $Id$ *)
-(* Elegant proof for continuity of fixed-point operator *)
-(* Loeckx & Sieber S.88                                 *)
-
-Goalw [Ifix_def] "Ifix F= lub (range (%i.%G. iterate i G UU)) F";
-by (stac thelub_fun 1);
-by (rtac refl 2);
-by (blast_tac (claset() addIs [ch2ch_fun, chainI, expand_fun_less RS iffD2,
-                               chain_iterate RS chainE]) 1); 
-qed "loeckx_sieber";
-
-(* 
-
-Idea: (%i.%G.iterate i G UU) is a chain of continuous functions and
-      Ifix is the lub of this chain. Hence Ifix is continuous.
-
------ The proof  in HOLCF ----------------------- 
-
-Since we already proved the theorem
-
-val cont_lubcfun = prove_goal Cfun2.thy 
-        "chain ?F ==> cont (%x. lub (range (%j. ?F j$x)))"
-
-
-it suffices to prove:
-
-Ifix  = (%f.lub (range (%j. (LAM f. iterate j f UU)$f)))
-
-and 
-
-cont (%f.lub (range (%j. (LAM f. iterate j f UU)$f)))
-
-Note that if we use the term 
-
-%i.%G.iterate i G UU instead of (%j.(LAM f. iterate j f UU))
-
-we cannot use the theorem cont_lubcfun    
-
-*)
-
-Goal "cont(Ifix)";
-by (res_inst_tac 
- [("t","Ifix"),("s","(%f. lub(range(%j.(LAM f. iterate j f UU)$f)))")]
-  ssubst 1);
-by (rtac ext 1);
-by (rewtac Ifix_def );
-by (subgoal_tac 
-  "range(% i. iterate i f UU) = range(%j.(LAM f. iterate j f UU)$f)" 1);
-by (etac arg_cong 1);
-by (subgoal_tac 
-        "(% i. iterate i f UU) = (%j.(LAM f. iterate j f UU)$f)" 1);
-by (etac arg_cong 1);
-by (rtac ext 1);
-by (stac beta_cfun 1);
-by (rtac  cont2cont_CF1L 1);
-by (rtac cont_iterate 1);
-by (rtac refl 1);
-by (rtac cont_lub_cfun 1);
-by (rtac chainI 1);
-by (strip_tac 1);
-by (rtac less_cfun_ext 1);
-by (stac beta_cfun 1);
-by (rtac  cont2cont_CF1L 1);
-by (rtac cont_iterate 1);
-by (stac beta_cfun 1);
-by (rtac  cont2cont_CF1L 1);
-by (rtac cont_iterate 1);
-by (rtac (chain_iterate RS chainE) 1);
-qed "cont_Ifix2'";
-
-(* the proof in little steps *)
-
-Goal "(% i. iterate i f UU) = (%j.(LAM f. iterate j f UU)$f)";
-by (rtac ext 1);
-by (simp_tac (simpset() addsimps [beta_cfun, cont2cont_CF1L, cont_iterate]) 1);
-qed "fix_lemma1";
-
-Goal "Ifix = (%f. lub(range(%j.(LAM f. iterate j f UU)$f)))";
-by (rtac ext 1);
-by (simp_tac (simpset() addsimps [Ifix_def, fix_lemma1]) 1);
-qed "fix_lemma2";
-
-(*
-- cont_lubcfun;
-val it = "chain ?F ==> cont (%x. lub (range (%j. ?F j$x)))" : thm   
-
-*)
-
-Goal "cont Ifix";
-by (stac fix_lemma2 1);
-by (rtac cont_lub_cfun 1);
-by (rtac chainI 1);
-by (rtac less_cfun_ext 1);
-by (stac beta_cfun 1);
-by (rtac  cont2cont_CF1L 1);
-by (rtac cont_iterate 1);
-by (stac beta_cfun 1);
-by (rtac  cont2cont_CF1L 1);
-by (rtac cont_iterate 1);
-by (rtac (chain_iterate RS chainE) 1);
-qed "cont_Ifix2''";
-