Theory Vcg

(*  Author:      Norbert Schirmer
    Maintainer:  Norbert Schirmer, norbert.schirmer at web de

Copyright (C) 2004-2008 Norbert Schirmer
Copyright (c) 2022 Apple Inc. All rights reserved.

*)

section ‹Facilitating the Hoare Logic›
theory Vcg
imports StateSpace "HOL-Statespace.StateSpaceLocale" Generalise
keywords "procedures" "hoarestate" :: thy_defn
begin

axiomatization NoBody::"('s,'p,'f) com"

ML_file ‹hoare.ML›

method_setup hoare = "Hoare.hoare"
  "raw verification condition generator for Hoare Logic"

method_setup hoare_raw = "Hoare.hoare_raw"
  "even more raw verification condition generator for Hoare Logic"

method_setup vcg = "Hoare.vcg"
  "verification condition generator for Hoare Logic"

method_setup vcg_step = "Hoare.vcg_step"
  "single verification condition generation step with light simplification"


method_setup hoare_rule = "Hoare.hoare_rule"
  "apply single hoare rule and solve certain sideconditions"

text ‹Variables of the programming language are represented as components
of a record. To avoid cluttering up the namespace of Isabelle with lots of
typical variable names, we append a unusual suffix at the end of each name by
parsing
›

definition list_multsel:: "'a list  nat list  'a list" (infixl !! 100)
  where "xs !! ns = map (nth xs) ns"

definition list_multupd:: "'a list  nat list  'a list  'a list"
  where "list_multupd xs ns ys = foldl (λxs (n,v). xs[n:=v]) xs (zip ns ys)"

nonterminal lmupdbinds and lmupdbind

syntax
  ― ‹multiple list update›
  "_lmupdbind":: "['a, 'a] => lmupdbind"    ((2_ [:=]/ _))
  "" :: "lmupdbind => lmupdbinds"    (‹_›)
  "_lmupdbinds" :: "[lmupdbind, lmupdbinds] => lmupdbinds"    (‹_,/ _›)
  "_LMUpdate" :: "['a, lmupdbinds] => 'a"    (‹_/[(_)] [900,0] 900)

syntax_consts
  "_lmupdbind" "_lmupdbinds" "_LMUpdate" == list_multupd

translations
  "_LMUpdate xs (_lmupdbinds b bs)" == "_LMUpdate (_LMUpdate xs b) bs"
  "xs[is[:=]ys]" == "CONST list_multupd xs is ys"


subsection ‹Some Fancy Syntax›


(* priority guidline:
 * If command should be atomic for the guard it must have at least priority 21.
 *)

text ‹reverse application›
definition rapp:: "'a  ('a  'b)  'b" (infixr |> 60)
  where "rapp x f = f x"


nonterminal
  newinit and
  newinits and
  locinit and
  locinits and
  switchcase and
  switchcases and
  grds and
  grd and
  bdy and
  basics and
  basic and
  basicblock

notation
  Skip  (SKIP) and
  Throw  (THROW)

syntax
  "_raise":: "'c  'c  ('a,'b,'f) com"       ((RAISE _ :==/ _) [30, 30] 23)
  "_seq"::"('s,'p,'f) com  ('s,'p,'f) com  ('s,'p,'f) com" (‹_;;/ _› [20, 21] 20)
  "_guarantee"     :: "'s set  grd"       (‹_ [1000] 1000)
  "_guaranteeStrip":: "'s set  grd"       (‹_# [1000] 1000)
  "_grd"           :: "'s set  grd"       (‹_› [1000] 1000)
  "_last_grd"      :: "grd  grds"         (‹_› 1000)
  "_grds"          :: "[grd, grds]  grds" (‹_,/ _› [999,1000] 1000)
  "_guards"        :: "grds  ('s,'p,'f) com  ('s,'p,'f) com"
                                            ((_/ _) [60, 21] 23)
  "_quote"       :: "'b => ('a => 'b)"
  "_antiquoteCur0"  :: "('a => 'b) => 'b"       (´_› [1000] 1000)
  "_antiquoteCur"  :: "('a => 'b) => 'b"
  "_antiquoteOld0"  :: "('a => 'b) => 'a => 'b"       (__› [1000,1000] 1000)
  "_antiquoteOld"  :: "('a => 'b) => 'a => 'b"
  "_Assert"      :: "'a => 'a set"            ((_) [0] 1000)
  "_AssertState" :: "idt  'a => 'a set"     ((_. _) [1000,0] 1000)
  "_Assign"      :: "'b => 'b => ('a,'p,'f) com"    ((_ :==/ _) [30, 30] 23)
  "_Init"        :: "ident  'c  'b  ('a,'p,'f) com"
                                             ((´_ :==⇘_/ _) [30,1000, 30] 23)
  "_GuardedAssign":: "'b => 'b => ('a,'p,'f) com"    ((_ :==g/ _) [30, 30] 23)
  "_newinit"      :: "[ident,'a]  newinit" ((2´_ :==/ _))
  ""             :: "newinit  newinits"    (‹_›)
  "_newinits"    :: "[newinit, newinits]  newinits" (‹_,/ _›)
  "_New"         :: "['a, 'b, newinits]  ('a,'b,'f) com"
                                            ((_ :==/(2 NEW _/ [_])) [30, 65, 0] 23)
  "_GuardedNew"  :: "['a, 'b, newinits]  ('a,'b,'f) com"
                                            ((_ :==g/(2 NEW _/ [_])) [30, 65, 0] 23)
  "_NNew"         :: "['a, 'b, newinits]  ('a,'b,'f) com"
                                            ((_ :==/(2 NNEW _/ [_])) [30, 65, 0] 23)
  "_GuardedNNew"  :: "['a, 'b, newinits]  ('a,'b,'f) com"
                                            ((_ :==g/(2 NNEW _/ [_])) [30, 65, 0] 23)

  "_Cond"        :: "'a bexp => ('a,'p,'f) com => ('a,'p,'f) com => ('a,'p,'f) com"
        ((0IF (_)/ (2THEN/ _)/ (2ELSE _)/ FI) [0, 0, 0] 71)
  "_Cond_no_else":: "'a bexp => ('a,'p,'f) com => ('a,'p,'f) com"
        ((0IF (_)/ (2THEN/ _)/ FI) [0, 0] 71)
  "_GuardedCond" :: "'a bexp => ('a,'p,'f) com => ('a,'p,'f) com => ('a,'p,'f) com"
        ((0IFg (_)/ (2THEN _)/ (2ELSE _)/ FI) [0, 0, 0] 71)
  "_GuardedCond_no_else":: "'a bexp => ('a,'p,'f) com => ('a,'p,'f) com"
        ((0IFg (_)/ (2THEN _)/ FI) [0, 0] 71)
  "_While_inv_var"   :: "'a bexp => 'a assn   ('a × 'a) set  bdy
                           ('a,'p,'f) com"
        ((0WHILE (_)/ INV (_)/ VAR (_) /_)  [25, 0, 0, 81] 71)
  "_WhileFix_inv_var"   :: "'a bexp => pttrn  ('z  'a assn)  
                            ('z  ('a × 'a) set)  bdy
                           ('a,'p,'f) com"
        ((0WHILE (_)/ FIX _./ INV (_)/ VAR (_) /_)  [25, 0, 0, 0, 81] 71)
  "_WhileFix_inv"   :: "'a bexp => pttrn  ('z  'a assn)   bdy
                           ('a,'p,'f) com"
        ((0WHILE (_)/ FIX _./ INV (_) /_)  [25, 0, 0, 81] 71)
  "_GuardedWhileFix_inv_var"   :: "'a bexp => pttrn  ('z  'a assn)  
                            ('z  ('a × 'a) set)  bdy
                           ('a,'p,'f) com"
        ((0WHILEg (_)/ FIX _./ INV (_)/ VAR (_) /_)  [25, 0, 0, 0, 81] 71)
  "_GuardedWhileFix_inv_var_hook"   :: "'a bexp  ('z  'a assn)  
                            ('z  ('a × 'a) set)  bdy
                           ('a,'p,'f) com"
  "_GuardedWhileFix_inv"   :: "'a bexp => pttrn  ('z  'a assn)   bdy
                           ('a,'p,'f) com"
        ((0WHILEg (_)/ FIX _./ INV (_)/_)  [25, 0, 0, 81] 71)

  "_GuardedWhile_inv_var"::
       "'a bexp => 'a assn   ('a × 'a) set  bdy  ('a,'p,'f) com"
        ((0WHILEg (_)/ INV (_)/ VAR (_) /_)  [25, 0, 0, 81] 71)
  "_While_inv"   :: "'a bexp => 'a assn => bdy => ('a,'p,'f) com"
        ((0WHILE (_)/ INV (_) /_)  [25, 0, 81] 71)
  "_GuardedWhile_inv"   :: "'a bexp => 'a assn => ('a,'p,'f) com => ('a,'p,'f) com"
        ((0WHILEg (_)/ INV (_) /_)  [25, 0, 81] 71)
  "_While"       :: "'a bexp => bdy => ('a,'p,'f) com"
        ((0WHILE (_) /_)  [25, 81] 71)
  "_GuardedWhile"       :: "'a bexp => bdy => ('a,'p,'f) com"
        ((0WHILEg (_) /_)  [25, 81] 71)
  "_While_guard"       :: "grds => 'a bexp => bdy => ('a,'p,'f) com"
        ((0WHILE (_/ (1_)) /_)  [1000,25,81] 71)
  "_While_guard_inv":: "grds 'a bexp'a assnbdy  ('a,'p,'f) com"
        ((0WHILE (_/ (1_)) INV (_) /_)  [1000,25,0,81] 71)
  "_While_guard_inv_var":: "grds 'a bexp'a assn('a×'a) set
                             bdy  ('a,'p,'f) com"
        ((0WHILE (_/ (1_)) INV (_)/ VAR (_) /_)  [1000,25,0,0,81] 71)
  "_WhileFix_guard_inv_var":: "grds 'a bexppttrn('z'a assn)('z('a×'a) set)
                             bdy  ('a,'p,'f) com"
        ((0WHILE (_/ (1_)) FIX _./ INV (_)/ VAR (_) /_)  [1000,25,0,0,0,81] 71)
  "_WhileFix_guard_inv":: "grds 'a bexppttrn('z'a assn)
                             bdy  ('a,'p,'f) com"
        ((0WHILE (_/ (1_)) FIX _./ INV (_)/_)  [1000,25,0,0,81] 71)

  "_Try_Catch":: "('a,'p,'f) com ('a,'p,'f) com  ('a,'p,'f) com"
        ((0TRY (_)/ (2CATCH _)/ END)  [0,0] 71)

  "_DoPre" :: "('a,'p,'f) com  ('a,'p,'f) com"
  "_Do" :: "('a,'p,'f) com  bdy" ((2DO/ (_)) /OD [0] 1000)
  "_Lab":: "'a bexp  ('a,'p,'f) com  bdy"
            (‹_/_› [1000,71] 81)
  "":: "bdy  ('a,'p,'f) com" (‹_›)
  "_Spec":: "pttrn  's set   ('s,'p,'f) com  's set  's set  ('s,'p,'f) com"
            ((ANNO _. _/ (_)/ _,/_) [0,1000,20,1000,1000] 60)
  "_SpecNoAbrupt":: "pttrn  's set   ('s,'p,'f) com  's set  ('s,'p,'f) com"
            ((ANNO _. _/ (_)/ _) [0,1000,20,1000] 60)
  "_LemAnno":: "'n  ('s,'p,'f) com  ('s,'p,'f) com"
              ((0 LEMMA (_)/ _ END) [1000,0] 71)
  "_locnoinit"    :: "ident  locinit"               (´_›)
  "_locinit"      :: "[ident,'a]  locinit"          ((2´_ :==/ _))
  ""             :: "locinit  locinits"             (‹_›)
  "_locinits"    :: "[locinit, locinits]  locinits" (‹_,/ _›)
  "_Loc":: "[locinits,('s,'p,'f) com]  ('s,'p,'f) com"
                                         ((2 LOC _;;/ (_) COL) [0,0] 71)
  "_Switch":: "('s  'v)  switchcases  ('s,'p,'f) com"
              ((0 SWITCH (_)/ _ END) [22,0] 71)
  "_switchcase":: "'v set  ('s,'p,'f) com  switchcase" (‹_/ _› )
  "_switchcasesSingle"  :: "switchcase  switchcases" (‹_›)
  "_switchcasesCons":: "switchcase  switchcases  switchcases"
                       (‹_/ | _›)
  "_Basic":: "basicblock  ('s,'p,'f) com" ((0BASIC/ (_)/ END) [22] 71)
  "_BasicBlock":: "basics  basicblock" (‹_›)
  "_BAssign"   :: "'b => 'b => basic"    ((_ :==/ _) [30, 30] 23)
  ""           :: "basic  basics"             (‹_›)
  "_basics"    :: "[basic, basics]  basics" (‹_,/ _›)

syntax (ASCII)
  "_Assert"      :: "'a => 'a set"           (({|_|}) [0] 1000)
  "_AssertState" :: "idt  'a  'a set"    (({|_. _|}) [1000,0] 1000)
  "_While_guard"       :: "grds => 'a bexp => bdy  ('a,'p,'f) com"
        ((0WHILE (_|-> /_) /_)  [0,0,1000] 71)
  "_While_guard_inv":: "grds'a bexp'a assnbdy  ('a,'p,'f) com"
        ((0WHILE (_|-> /_) INV (_) /_)  [0,0,0,1000] 71)
  "_guards" :: "grds  ('s,'p,'f) com  ('s,'p,'f) com" ((_|->_ ) [60, 21] 23)

syntax (output)
  "_hidden_grds"      :: "grds" ()

translations
  "_Do c" => "c"
  "b c" => "CONST condCatch c b SKIP"
  "b (_DoPre c)" <= "CONST condCatch c b SKIP"
  "l (CONST whileAnnoG gs b I V c)" <= "l (_DoPre (CONST whileAnnoG gs b I V c))"
  "l (CONST whileAnno b I V c)" <= "l (_DoPre (CONST whileAnno b I V c))"
  "CONST condCatch c b SKIP" <= "(_DoPre (CONST condCatch c b SKIP))"
  "_Do c" <= "_DoPre c"
  "c;; d" == "CONST Seq c d"
  "_guarantee g" => "(CONST True, g)"
  "_guaranteeStrip g" == "CONST guaranteeStripPair (CONST True) g"
  "_grd g" => "(CONST False, g)"
  "_grds g gs" => "g#gs"
  "_last_grd g" => "[g]"
  "_guards gs c" == "CONST guards gs c"

  "{|s. P|}"                   == "{|_antiquoteCur((=) s)  P |}"
  "{|b|}"                   => "CONST Collect (_quote b)"
  "IF b THEN c1 ELSE c2 FI" => "CONST Cond {|b|} c1 c2"
  "IF b THEN c1 FI"         ==  "IF b THEN c1 ELSE SKIP FI"
  "IFg b THEN c1 FI"        ==  "IFg b THEN c1 ELSE SKIP FI"

  "_While_inv_var b I V c"          => "CONST whileAnno {|b|} I V c"
  "_While_inv_var b I V (_DoPre c)" <= "CONST whileAnno {|b|} I V c"
  "_While_inv b I c"                 == "_While_inv_var b I (CONST undefined) c"
  "_While b c"                       == "_While_inv b {|CONST undefined|} c"

  "_While_guard_inv_var gs b I V c"          => "CONST whileAnnoG gs {|b|} I V c"
(*  "_While_guard_inv_var gs b I V (_DoPre c)" <= "CONST whileAnnoG gs {|b|} I V c"*)
  "_While_guard_inv gs b I c"       == "_While_guard_inv_var gs b I (CONST undefined) c"
  "_While_guard gs b c"             == "_While_guard_inv gs b {|CONST undefined|} c"

  "_GuardedWhile_inv b I c"  == "_GuardedWhile_inv_var b I (CONST undefined) c"
  "_GuardedWhile b c"        == "_GuardedWhile_inv b {|CONST undefined|} c"
(*  "sA"                      => "A s"*)
  "TRY c1 CATCH c2 END"     == "CONST Catch c1 c2"
  "ANNO s. P c Q,A" => "CONST specAnno (λs. P) (λs. c) (λs. Q) (λs. A)"
  "ANNO s. P c Q" == "ANNO s. P c Q,{}"

  "_WhileFix_inv_var b z I V c" => "CONST whileAnnoFix {|b|} (λz. I) (λz. V) (λz. c)"
  "_WhileFix_inv_var b z I V (_DoPre c)" <= "_WhileFix_inv_var {|b|} z I V c"
  "_WhileFix_inv b z I c" == "_WhileFix_inv_var b z I (CONST undefined) c"

  "_GuardedWhileFix_inv b z I c" == "_GuardedWhileFix_inv_var b z I (CONST undefined) c"

  "_GuardedWhileFix_inv_var b z I V c" =>
                         "_GuardedWhileFix_inv_var_hook {|b|} (λz. I) (λz. V) (λz. c)"

  "_WhileFix_guard_inv_var gs b z I V c" =>
                                      "CONST whileAnnoGFix gs {|b|} (λz. I) (λz. V) (λz. c)"
  "_WhileFix_guard_inv_var gs b z I V (_DoPre c)" <=
                                      "_WhileFix_guard_inv_var gs {|b|} z I V c"
  "_WhileFix_guard_inv gs b z I c" == "_WhileFix_guard_inv_var gs b z I (CONST undefined) c"
  "LEMMA x c END" == "CONST lem x c"
translations
 "(_switchcase V c)" => "(V,c)"
 "(_switchcasesSingle b)" => "[b]"
 "(_switchcasesCons b bs)" => "CONST Cons b bs"
 "(_Switch v vs)" => "CONST switch (_quote v) vs"

parse_ast_translation let
    fun tr c asts = Ast.mk_appl (Ast.Constant c) (map Ast.strip_positions asts)
  in
   [(@{syntax_const "_antiquoteCur0"}, K (tr @{syntax_const "_antiquoteCur"})),
    (@{syntax_const "_antiquoteOld0"}, K (tr @{syntax_const "_antiquoteOld"}))]
  end

print_ast_translation let
    fun tr c asts = Ast.mk_appl (Ast.Constant c) asts
  in
   [(@{syntax_const "_antiquoteCur"}, K (tr @{syntax_const "_antiquoteCur0"})),
    (@{syntax_const "_antiquoteOld"}, K (tr @{syntax_const "_antiquoteOld0"}))]
  end

print_ast_translation let
    fun dest_abs (Ast.Appl [Ast.Constant @{syntax_const "_abs"}, x, t]) = (x, t)
      | dest_abs _ = raise Match;
    fun spec_tr' [P, c, Q, A] =
      let
        val (x',P') = dest_abs P;
        val (_ ,c') = dest_abs c;
        val (_ ,Q') = dest_abs Q;
        val (_ ,A') = dest_abs A;
      in
        if (A' = Ast.Constant @{const_syntax bot})
        then Ast.mk_appl (Ast.Constant @{syntax_const "_SpecNoAbrupt"}) [x', P', c', Q']
        else Ast.mk_appl (Ast.Constant @{syntax_const "_Spec"}) [x', P', c', Q', A']
      end;
    fun whileAnnoFix_tr' [b, I, V, c] =
      let
        val (x',I') = dest_abs I;
        val (_ ,V') = dest_abs V;
        val (_ ,c') = dest_abs c;
      in
        Ast.mk_appl (Ast.Constant @{syntax_const "_WhileFix_inv_var"}) [b, x', I', V', c']
      end;
  in
   [(@{const_syntax specAnno}, K spec_tr'),
    (@{const_syntax whileAnnoFix}, K whileAnnoFix_tr')]
  end



syntax
  "_faccess"  :: "'ref  ('ref  'v)  'v"
   (‹__› [65,1000] 100)

syntax (ASCII)
  "_faccess"  :: "'ref  ('ref  'v)  'v"
   (‹_->_› [65,1000] 100)

translations

 "pf"        =>  "f p"
 "g(_antiquoteCur f)" <= "_antiquoteCur f g"


nonterminal par and pars and actuals

syntax
  "_par" :: "'a  par"                                (‹_›)
  ""    :: "par  pars"                               (‹_›)
  "_pars" :: "[par,pars]  pars"                      (‹_,/_›)
  "_actuals" :: "pars  actuals"                      ('(_'))
  "_actuals_empty" :: "actuals"                        ('('))

syntax "_Call" :: "'p  actuals  (('a,string,'f) com)" (CALL __› [1000,1000] 21)
       "_GuardedCall" :: "'p  actuals  (('a,string,'f) com)" (CALLg __› [1000,1000] 21)
       "_CallAss":: "'a  'p  actuals  (('a,string,'f) com)"
             (‹_ :== CALL __› [30,1000,1000] 21)
       "_Call_exn" :: "'p  actuals  (('a,string,'f) com)" (CALLe __› [1000,1000] 21)
       "_CallAss_exn":: "'a  'p  actuals  (('a,string,'f) com)"
             (‹_ :== CALLe __› [30,1000,1000] 21)
       "_Proc" :: "'p  actuals  (('a,string,'f) com)" (PROC __› 21)
       "_ProcAss":: "'a  'p  actuals  (('a,string,'f) com)"
             (‹_ :== PROC __› [30,1000,1000] 21)
       "_GuardedCallAss":: "'a  'p  actuals  (('a,string,'f) com)"
             (‹_ :== CALLg __› [30,1000,1000] 21)
       "_DynCall" :: "'p  actuals  (('a,string,'f) com)" (DYNCALL __› [1000,1000] 21)
       "_GuardedDynCall" :: "'p  actuals  (('a,string,'f) com)" (DYNCALLg __› [1000,1000] 21)
       "_DynCallAss":: "'a  'p  actuals  (('a,string,'f) com)"
             (‹_ :== DYNCALL __› [30,1000,1000] 21)
       "_DynCall_exn" :: "'p  actuals  (('a,string,'f) com)" (DYNCALLe __› [1000,1000] 21)
       "_DynCallAss_exn":: "'a  'p  actuals  (('a,string,'f) com)"
             (‹_ :== DYNCALLe __› [30,1000,1000] 21)
       "_GuardedDynCallAss":: "'a  'p  actuals  (('a,string,'f) com)"
             (‹_ :== DYNCALLg __› [30,1000,1000] 21)

       "_Bind":: "['s  'v, idt, 'v  ('s,'p,'f) com]  ('s,'p,'f) com"
                      (‹_  _./ _› [22,1000,21] 21)
       "_bseq"::"('s,'p,'f) com  ('s,'p,'f) com  ('s,'p,'f) com"
           (‹_/ _› [22, 21] 21)
       "_FCall" :: "['p,actuals,idt,(('a,string,'f) com)] (('a,string,'f) com)"
                      (CALL __  _./ _› [1000,1000,1000,21] 21)



translations
"_Bind e i c" == "CONST bind (_quote e) (λi. c)"
"_FCall p acts i c" == "_FCall p acts (λi. c)"
"_bseq c d" == "CONST bseq c d"



nonterminal modifyargs

syntax
  "_may_modify" :: "['a,'a,modifyargs]  bool"
        (‹_ may'_only'_modify'_globals _ in [_] [100,100,0] 100)
  "_may_not_modify" :: "['a,'a]  bool"
        (‹_ may'_not'_modify'_globals _› [100,100] 100)
  "_may_modify_empty" :: "['a,'a]  bool"
        (‹_ may'_only'_modify'_globals _ in [] [100,100] 100)
  "_modifyargs" :: "[id,modifyargs]  modifyargs" (‹_,/ _›)
  ""            :: "id => modifyargs"              (‹_›)

translations
"s may_only_modify_globals Z in []" => "s may_not_modify_globals Z"


definition Let':: "['a, 'a => 'b] => 'b"
  where "Let' = Let"

ML_file ‹hoare_syntax.ML›


parse_translation let
    val argsC = @{syntax_const "_modifyargs"};
    val globalsN = "globals";
    val ex = @{const_syntax mex};
    val eq = @{const_syntax meq};
    val varn = Hoare.varname;

    fun extract_args (Const (argsC,_)$Free (n,_)$t) = varn n::extract_args t
      | extract_args (Free (n,_)) = [varn n]
      | extract_args t            = raise TERM ("extract_args", [t])

    fun idx [] y = error "idx: element not in list"
     |  idx (x::xs) y = if x=y then 0 else (idx xs y)+1

    fun gen_update ctxt names (name,t) =
        Hoare_Syntax.update_comp ctxt NONE [] false true name (Bound (idx names name)) t

    fun gen_updates ctxt names t = Library.foldr (gen_update ctxt names) (names,t)

    fun gen_ex (name,t) = Syntax.const ex $ Abs (name,dummyT,t)

    fun gen_exs names t = Library.foldr gen_ex (names,t)


    fun tr ctxt s Z names =
      let val upds = gen_updates ctxt (rev names) (Syntax.free globalsN$Z);
          val eq   = Syntax.const eq $ (Syntax.free globalsN$s) $ upds;
      in gen_exs names eq end;

    fun may_modify_tr ctxt [s,Z,names] = tr ctxt s Z
                                           (sort_strings (extract_args names))
    fun may_not_modify_tr ctxt [s,Z] = tr ctxt s Z []
  in
   [(@{syntax_const "_may_modify"}, may_modify_tr),
    (@{syntax_const "_may_not_modify"}, may_not_modify_tr)]
  end


print_translation let
    val argsC = @{syntax_const "_modifyargs"};
    val chop = Hoare.chopsfx Hoare.deco;

    fun get_state ( _ $ _ $ t) = get_state t  (* for record-updates*)
      | get_state ( _ $ _ $ _ $ _ $ _ $ t) = get_state t (* for statespace-updates *)
      | get_state (globals$(s as Const (@{syntax_const "_free"},_) $ Free _)) = s
      | get_state (globals$(s as Const (@{syntax_const "_bound"},_) $ Free _)) = s
      | get_state (globals$(s as Const (@{syntax_const "_var"},_) $ Var _)) = s
      | get_state (globals$(s as Const _)) = s
      | get_state (globals$(s as Free _)) = s
      | get_state (globals$(s as Bound _)) = s
      | get_state t              = raise Match;

    fun mk_args [n] = Syntax.free (chop n)
      | mk_args (n::ns) = Syntax.const argsC $ Syntax.free (chop n) $ mk_args ns
      | mk_args _      = raise Match;

    fun tr' names (Abs (n,_,t)) = tr' (n::names) t
      | tr' names (Const (@{const_syntax mex},_) $ t) = tr' names t
      | tr' names (Const (@{const_syntax meq},_) $ (globals$s) $ upd) =
            let val Z = get_state upd;

            in (case names of
                  [] => Syntax.const @{syntax_const "_may_not_modify"} $ s $ Z
                | xs => Syntax.const @{syntax_const "_may_modify"} $ s $ Z $ mk_args (rev names))
            end;

    fun may_modify_tr' [t] = tr' [] t
    fun may_not_modify_tr' [_$s,_$Z] = Syntax.const @{syntax_const "_may_not_modify"} $ s $ Z
  in
    [(@{const_syntax mex}, K may_modify_tr'),
     (@{const_syntax meq}, K may_not_modify_tr')]
  end


(* decorate state components with suffix *)
(*
parse_ast_translation {*
 [(@{syntax_const "_Free"}, K Hoare_Syntax.free_arg_ast_tr),
  (@{syntax_const "_In"}, K Hoare_Syntax.in_arg_ast_tr),
  (@{syntax_const "_Where"}, K Hoare_Syntax.where_arg_ast_tr @{syntax_const "_Where"}),
  (@{syntax_const "_WhereElse"}, K Hoare_Syntax.where_arg_ast_tr @{syntax_const "_WhereElse"})
]
*}
*)
(*
parse_ast_translation {*
 [(@{syntax_const "_antiquoteOld"},
    Hoare_Syntax.antiquoteOld_varname_tr @{syntax_const "_antiquoteOld"})]
*}
*)


parse_translation [(@{syntax_const "_antiquoteCur"},
    K (Hoare_Syntax.antiquote_varname_tr @{syntax_const "_antiquoteCur"}))]


parse_translation [(@{syntax_const "_antiquoteOld"}, Hoare_Syntax.antiquoteOld_tr),
  (@{syntax_const "_Call"}, Hoare_Syntax.call_tr false false []),
  (@{syntax_const "_Call_exn"}, Hoare_Syntax.call_tr false true []),
  (@{syntax_const "_FCall"}, Hoare_Syntax.fcall_tr),
  (@{syntax_const "_CallAss"}, Hoare_Syntax.call_ass_tr false false []),
  (@{syntax_const "_CallAss_exn"}, Hoare_Syntax.call_ass_tr false true []),
  (@{syntax_const "_GuardedCall"}, Hoare_Syntax.call_tr false true []),
  (@{syntax_const "_GuardedCallAss"}, Hoare_Syntax.call_ass_tr false true []),
  (@{syntax_const "_Proc"}, Hoare_Syntax.proc_tr),
  (@{syntax_const "_ProcAss"}, Hoare_Syntax.proc_ass_tr),
  (@{syntax_const "_DynCall"}, Hoare_Syntax.call_tr true false []),
  (@{syntax_const "_DynCall_exn"}, Hoare_Syntax.call_tr true true []),
  (@{syntax_const "_DynCallAss"}, Hoare_Syntax.call_ass_tr true false []),
  (@{syntax_const "_DynCallAss_exn"}, Hoare_Syntax.call_ass_tr true true []),
  (@{syntax_const "_GuardedDynCall"}, Hoare_Syntax.call_tr true true []),
  (@{syntax_const "_GuardedDynCallAss"}, Hoare_Syntax.call_ass_tr true true []),
  (@{syntax_const "_BasicBlock"}, Hoare_Syntax.basic_assigns_tr)]

(*
  (@{syntax_const "_Call"}, Hoare_Syntax.call_ast_tr),
  (@{syntax_const "_CallAss"}, Hoare_Syntax.call_ass_ast_tr),
  (@{syntax_const "_GuardedCall"}, Hoare_Syntax.guarded_call_ast_tr),
  (@{syntax_const "_GuardedCallAss"}, Hoare_Syntax.guarded_call_ass_ast_tr)
*)

parse_translation let
    fun quote_tr ctxt [t] = Hoare_Syntax.quote_tr ctxt @{syntax_const "_antiquoteCur"} t
      | quote_tr ctxt ts = raise TERM ("quote_tr", ts);
  in [(@{syntax_const "_quote"}, quote_tr)] end



parse_translation [(@{syntax_const "_Assign"}, Hoare_Syntax.assign_tr),
  (@{syntax_const "_raise"}, Hoare_Syntax.raise_tr),
  (@{syntax_const "_New"}, Hoare_Syntax.new_tr),
  (@{syntax_const "_NNew"}, Hoare_Syntax.nnew_tr),
  (@{syntax_const "_GuardedAssign"}, Hoare_Syntax.guarded_Assign_tr),
  (@{syntax_const "_GuardedNew"}, Hoare_Syntax.guarded_New_tr),
  (@{syntax_const "_GuardedNNew"}, Hoare_Syntax.guarded_NNew_tr),
  (@{syntax_const "_GuardedWhile_inv_var"}, Hoare_Syntax.guarded_While_tr),
  (@{syntax_const "_GuardedWhileFix_inv_var_hook"}, Hoare_Syntax.guarded_WhileFix_tr),
  (@{syntax_const "_GuardedCond"}, Hoare_Syntax.guarded_Cond_tr),
  (@{syntax_const "_Basic"}, Hoare_Syntax.basic_tr)]

parse_translation [(@{syntax_const "_Init"}, Hoare_Syntax.init_tr),
  (@{syntax_const "_Loc"}, Hoare_Syntax.loc_tr)]


print_translation [(@{const_syntax Basic}, Hoare_Syntax.assign_tr'),
  (@{const_syntax raise}, Hoare_Syntax.raise_tr'),
  (@{const_syntax Basic}, Hoare_Syntax.new_tr'),
  (@{const_syntax Basic}, Hoare_Syntax.init_tr'),
  (@{const_syntax Spec}, Hoare_Syntax.nnew_tr'),
  (@{const_syntax block}, Hoare_Syntax.loc_tr'),
  (@{const_syntax Collect}, Hoare_Syntax.assert_tr'),
  (@{const_syntax Cond}, Hoare_Syntax.bexp_tr' "_Cond"),
  (@{const_syntax switch}, Hoare_Syntax.switch_tr'),
  (@{const_syntax Basic}, Hoare_Syntax.basic_tr'),
  (@{const_syntax guards}, Hoare_Syntax.guards_tr'),
  (@{const_syntax whileAnnoG}, Hoare_Syntax.whileAnnoG_tr'),
  (@{const_syntax whileAnnoGFix}, Hoare_Syntax.whileAnnoGFix_tr'),
  (@{const_syntax bind}, Hoare_Syntax.bind_tr')]


print_translation let
    fun spec_tr' ctxt ((coll as Const _)$
                   ((splt as Const _) $ (t as (Abs (s,T,p))))::ts) =
          let
            fun selector (Const (c, T)) = Hoare.is_state_var c
              | selector (Const (@{syntax_const "_free"}, _) $ (Free (c, T))) =
                  Hoare.is_state_var c
              | selector _ = false;
          in
            if Hoare_Syntax.antiquote_applied_only_to selector p then
              Syntax.const @{const_syntax Spec} $ coll $
                (splt $ Hoare_Syntax.quote_mult_tr' ctxt selector
                    Hoare_Syntax.antiquoteCur Hoare_Syntax.antiquoteOld  (Abs (s,T,t)))
             else raise Match
          end
      | spec_tr' _ ts = raise Match
  in [(@{const_syntax Spec}, spec_tr')] end

syntax
"_Measure":: "('a  nat)  ('a × 'a) set"
      (MEASURE _› [22] 1)
"_Mlex":: "('a  nat)  ('a × 'a) set  ('a × 'a) set"
      (infixr <*MLEX*> 30)

syntax_consts
"_Measure" == measure and
"_Mlex" == mlex_prod

translations
 "MEASURE f"       => "(CONST measure) (_quote f)"
 "f <*MLEX*> r"       => "(_quote f) <*mlex*> r"



print_translation let
    fun selector (Const (c,T)) = Hoare.is_state_var c
      | selector _ = false;

    fun measure_tr' ctxt ((t as (Abs (_,_,p)))::ts) =
          if Hoare_Syntax.antiquote_applied_only_to selector p
          then Hoare_Syntax.app_quote_tr' ctxt (Syntax.const @{syntax_const "_Measure"}) (t::ts)
          else raise Match
      | measure_tr' _ _ = raise Match

    fun mlex_tr' ctxt ((t as (Abs (_,_,p)))::r::ts) =
          if Hoare_Syntax.antiquote_applied_only_to selector p
          then Hoare_Syntax.app_quote_tr' ctxt (Syntax.const @{syntax_const "_Mlex"}) (t::r::ts)
          else raise Match
      | mlex_tr' _ _ = raise Match

  in
   [(@{const_syntax measure}, measure_tr'),
    (@{const_syntax mlex_prod}, mlex_tr')]
  end


print_translation [(@{const_syntax call}, Hoare_Syntax.call_tr'),
  (@{const_syntax dynCall}, Hoare_Syntax.dyn_call_tr'),
  (@{const_syntax call_exn}, Hoare_Syntax.call_exn_tr'),
  (@{const_syntax dynCall_exn}, Hoare_Syntax.dyn_call_exn_tr'),
  (@{const_syntax fcall}, Hoare_Syntax.fcall_tr'),
  (@{const_syntax Call}, Hoare_Syntax.proc_tr')]

end