# HG changeset patch
# User nipkow
# Date 794654750 -3600
# Node ID 534955033ed2ad34211e0a01ba66ee1a24f8bfaf
# Parent  621be7ec81d7530a23b21934493c0d001abb2f28
Added pretty-printing coments

diff -r 621be7ec81d7 -r 534955033ed2 src/HOL/IMP/Hoare.thy
--- a/src/HOL/IMP/Hoare.thy	Tue Mar 07 15:00:34 1995 +0100
+++ b/src/HOL/IMP/Hoare.thy	Wed Mar 08 10:25:50 1995 +0100
@@ -8,7 +8,42 @@
 
 Hoare = Denotation +
 consts
-  spec:: "[state=>bool,com,state=>bool] => bool" ("{{(1_)}}/ (_)/ {{(1_)}}" 10)
+  spec :: "[state=>bool,com,state=>bool] => bool"
+(* syntax "@spec" :: "[bool,com,bool] => bool" *)
+          ("{{(1_)}}/ (_)/ {{(1_)}}" 10)
 defs
   spec_def "spec P c Q == !s t. <s,t> : C(c) --> P s --> Q t"
 end
+(* Pretty-printing of assertions.
+   Not very helpful as long as programs are not pretty-printed.
+ML
+
+local open Syntax
+
+fun is_loc a = let val ch = hd(explode a)
+               in ord "A" <= ord ch andalso ord ch <= ord "Z" end;
+
+fun tr(s$t,i) = tr(s,i)$tr(t,i)
+  | tr(Abs(x,T,u),i) = Abs(x,T,tr(u,i+1))
+  | tr(t as Free(a,T),i) = if is_loc a then Bound(i) $ free(a) else t
+  | tr(t,_) = t;
+
+fun cond_tr(p) = Abs("",dummyT,tr(p,0))
+
+fun spec_tr[p,c,q] = const"spec" $ cond_tr p $ c $ cond_tr q;
+
+fun tr'(t as (Bound j $ (u as Free(a,_))),i) = if i=j then u else t
+  | tr'(s$t,i) = tr'(s,i)$tr'(t,i)
+  | tr'(Abs(x,T,u),i) = Abs(x,T,tr'(u,i+1))
+  | tr'(t,_) = t;
+
+fun spec_tr'[Abs(_,_,p),c,Abs(_,_,q)] =
+  const"@spec" $ tr'(p,0) $ c $ tr'(q,0);
+
+in
+
+val parse_translation = [("@spec", spec_tr)];
+val print_translation = [("spec", spec_tr')];
+
+end
+*)