(* Title: HOLCF/domain/extender.ML
ID: $Id$
Author: David von Oheimb and Markus Wenzel
License: GPL (GNU GENERAL PUBLIC LICENSE)
Theory extender for domain section, including new-style theory syntax.
*)
signature DOMAIN_EXTENDER =
sig
val add_domain: string *
((bstring * string list) * (string * mixfix * (bool * string * string) list) list) list
-> theory -> theory
end;
structure Domain_Extender: DOMAIN_EXTENDER =
struct
open Domain_Library;
(* ----- general testing and preprocessing of constructor list -------------- *)
fun check_and_sort_domain (dtnvs: (string * typ list) list, cons'' :
((string * mixfix * (bool*string*typ) list) list) list) sg =
let
val defaultS = Sign.defaultS sg;
val test_dupl_typs = (case duplicates (map fst dtnvs) of
[] => false | dups => error ("Duplicate types: " ^ commas_quote dups));
val test_dupl_cons = (case duplicates (map first (flat cons'')) of
[] => false | dups => error ("Duplicate constructors: "
^ commas_quote dups));
val test_dupl_sels = (case duplicates
(map second (flat (map third (flat cons'')))) of
[] => false | dups => error("Duplicate selectors: "^commas_quote dups));
val test_dupl_tvars = exists(fn s=>case duplicates(map(fst o rep_TFree)s)of
[] => false | dups => error("Duplicate type arguments: "
^commas_quote dups)) (map snd dtnvs);
(* test for free type variables, illegal sort constraints on rhs,
non-pcpo-types and invalid use of recursive type;
replace sorts in type variables on rhs *)
fun analyse_equation ((dname,typevars),cons') =
let
val tvars = map rep_TFree typevars;
fun distinct_name s = "'"^Sign.base_name dname^"_"^s;
val distinct_typevars = map (fn (n,sort) =>
TFree (distinct_name n,sort)) tvars;
fun rm_sorts (TFree(s,_)) = TFree(s,[])
| rm_sorts (Type(s,ts)) = Type(s,remove_sorts ts)
| rm_sorts (TVar(s,_)) = TVar(s,[])
and remove_sorts l = map rm_sorts l;
fun analyse(TFree(v,s)) = (case assoc_string(tvars,v) of
None => error ("Free type variable " ^ v ^ " on rhs.")
| Some sort => if eq_set_string (s,defaultS) orelse
eq_set_string (s,sort )
then TFree(distinct_name v,sort)
else error ("Additional constraint on rhs "^
"for type variable "^quote v))
(** BUG OR FEATURE?: mutual recursion may use different arguments **)
| analyse(Type(s,typl)) = (case assoc_string((*dtnvs*)
[(dname,typevars)],s) of
None => Type(s,map analyse typl)
| Some typevars => if remove_sorts typevars = remove_sorts typl
then Type(s,map analyse typl)
else error ("Recursion of type " ^ s ^
" with different arguments"))
| analyse(TVar _) = Imposs "extender:analyse";
fun check_pcpo t = (pcpo_type sg t orelse error(
"Type not of sort pcpo: "^string_of_typ sg t); t);
val analyse_con = upd_third (map (upd_third (check_pcpo o analyse)));
in ((dname,distinct_typevars), map analyse_con cons') end;
in ListPair.map analyse_equation (dtnvs,cons'')
end; (* let *)
(* ----- calls for building new thy and thms -------------------------------- *)
fun add_domain (comp_dnam,eqs''') thy''' = let
val sg''' = sign_of thy''';
val dtnvs = map ((fn (dname,vs) =>
(Sign.full_name sg''' dname,map (str2typ sg''') vs))
o fst) eqs''';
val cons''' = map snd eqs''';
fun thy_type (dname,tvars) = (Sign.base_name dname, length tvars, NoSyn);
fun thy_arity (dname,tvars) = (dname, map (snd o rep_TFree) tvars, pcpoS);
val thy'' = thy''' |> Theory.add_types (map thy_type dtnvs)
|> Theory.add_arities_i (map thy_arity dtnvs);
val sg'' = sign_of thy'';
val cons''=map (map (upd_third (map (upd_third (str2typ sg''))))) cons''';
val eqs' = check_and_sort_domain (dtnvs,cons'') sg'';
val thy' = thy'' |> Domain_Syntax.add_syntax (comp_dnam,eqs');
val dts = map (Type o fst) eqs';
fun strip ss = drop (find_index_eq "'" ss +1, ss);
fun typid (Type (id,_)) =
let val c = hd (Symbol.explode (Sign.base_name id))
in if Symbol.is_letter c then c else "t" end
| typid (TFree (id,_) ) = hd (strip (tl (Symbol.explode id)))
| typid (TVar ((id,_),_)) = hd (tl (Symbol.explode id));
fun cons cons' = (map (fn (con,syn,args) =>
((Syntax.const_name con syn),
ListPair.map (fn ((lazy,sel,tp),vn) => ((lazy,
find_index_eq tp dts),
sel,vn))
(args,(mk_var_names(map (typid o third) args)))
)) cons') : cons list;
val eqs = map (fn (dtnvs,cons') => (dtnvs,cons cons')) eqs' : eq list;
val thy = thy' |> Domain_Axioms.add_axioms (comp_dnam,eqs);
val (theorems_thy, (rewss, take_rews)) = (foldl_map (fn (thy0,eq) =>
Domain_Theorems.theorems (eq,eqs) thy0) (thy,eqs))
|>>> Domain_Theorems.comp_theorems (comp_dnam, eqs);
in
theorems_thy
|> Theory.add_path (Sign.base_name comp_dnam)
|> (#1 o (PureThy.add_thmss [(("rews", flat rewss @ take_rews), [])]))
|> Theory.parent_path
end;
(** outer syntax **)
local structure P = OuterParse and K = OuterSyntax.Keyword in
val dest_decl =
P.$$$ "(" |-- Scan.optional (P.$$$ "lazy" >> K true) false --
P.name -- (P.$$$ "::" |-- P.typ) --| P.$$$ ")" >> P.triple1;
val cons_decl =
P.name -- Scan.repeat dest_decl -- P.opt_mixfix --| P.marg_comment
>> (fn ((c, ds), mx) => (c, mx, ds));
val domain_decl = (P.type_args -- P.name >> Library.swap) -- (P.$$$ "=" |-- P.enum1 "|" cons_decl);
val domains_decl =
Scan.option (P.$$$ "(" |-- P.name --| P.$$$ ")") -- P.and_list1 domain_decl
>> (fn (opt_name, doms) =>
(case opt_name of None => space_implode "_" (map (#1 o #1) doms) | Some s => s, doms));
val domainP =
OuterSyntax.command "domain" "define recursive domains (HOLCF)" K.thy_decl
(domains_decl >> (Toplevel.theory o add_domain));
val _ = OuterSyntax.add_keywords ["lazy"];
val _ = OuterSyntax.add_parsers [domainP];
end;
end;