(*  Title:      HOL/IOA/example/Spec.thy
    ID:         $Id: Spec.thy,v 1.4 2005/09/03 14:50:26 wenzelm Exp $
    Author:     Olaf Müller
*)

header {* The specification of a memory *}

theory Spec
imports IOA Action
begin

consts

spec_sig   :: "action signature"
spec_trans :: "(action, nat set * bool)transition set"
spec_ioa   :: "(action, nat set * bool)ioa"

defs

sig_def: "spec_sig == (UN l.{Free l} Un {New},
                     UN l.{Loc l},
                     {})"

trans_def: "spec_trans ==
 {tr. let s = fst(tr); used = fst s; c = snd s;
          t = snd(snd(tr)); used' = fst t; c' = snd t
      in
      case fst(snd(tr))
      of
      New       => used' = used & c'  |
      Loc l     => c & l~:used  & used'= used Un {l} & ~c'   |
      Free l    => used'=used - {l} & c'=c}"

ioa_def: "spec_ioa == (spec_sig, {({},False)}, spec_trans,{},{})"

ML {* use_legacy_bindings (the_context ()) *}

end
