(* Title: Pure/theory.ML
ID: $Id$
Author: Lawrence C Paulson and Markus Wenzel
Logical theory content: axioms, definitions, oracles.
*)
signature BASIC_THEORY =
sig
type theory
type theory_ref
val sign_of: theory -> theory (*obsolete*)
val rep_theory: theory ->
{axioms: term NameSpace.table,
defs: Defs.graph,
oracles: ((theory * Object.T -> term) * stamp) NameSpace.table}
val parents_of: theory -> theory list
val ancestors_of: theory -> theory list
val eq_thy: theory * theory -> bool
val subthy: theory * theory -> bool
val cert_axm: theory -> string * term -> string * term
val read_def_axm: theory * (indexname -> typ option) * (indexname -> sort option) ->
string list -> string * string -> string * term
val read_axm: theory -> string * string -> string * term
val inferT_axm: theory -> string * term -> string * term
end
signature THEORY =
sig
include BASIC_THEORY
include SIGN_THEORY
val begin_theory: string -> theory list -> theory
val end_theory: theory -> theory
val checkpoint: theory -> theory
val copy: theory -> theory
val init_data: theory -> theory
val axiom_space: theory -> NameSpace.T
val oracle_space: theory -> NameSpace.T
val axioms_of: theory -> (string * term) list
val all_axioms_of: theory -> (string * term) list
val defs_of : theory -> Defs.graph
val self_ref: theory -> theory_ref
val deref: theory_ref -> theory
val merge: theory * theory -> theory (*exception TERM*)
val merge_refs: theory_ref * theory_ref -> theory_ref (*exception TERM*)
val requires: theory -> string -> string -> unit
val assert_super: theory -> theory -> theory
val add_axioms: (bstring * string) list -> theory -> theory
val add_axioms_i: (bstring * term) list -> theory -> theory
val add_defs: bool -> (bstring * string) list -> theory -> theory
val add_defs_i: bool -> (bstring * term) list -> theory -> theory
val add_finals: bool -> string list -> theory -> theory
val add_finals_i: bool -> term list -> theory -> theory
val add_oracle: bstring * (theory * Object.T -> term) -> theory -> theory
end
structure Theory: THEORY =
struct
(** type theory **)
(* context operations *)
type theory = Context.theory;
type theory_ref = Context.theory_ref;
val eq_thy = Context.eq_thy;
val subthy = Context.subthy;
val parents_of = Context.parents_of;
val ancestors_of = Context.ancestors_of;
val self_ref = Context.self_ref;
val deref = Context.deref;
val merge = Context.merge;
val merge_refs = Context.merge_refs;
val begin_theory = Sign.local_path oo Context.begin_thy Sign.pp;
val end_theory = Context.finish_thy;
val checkpoint = Context.checkpoint_thy;
val copy = Context.copy_thy;
(* signature operations *)
val sign_of = I;
structure SignTheory: SIGN_THEORY = Sign;
open SignTheory;
(** datatype thy **)
datatype thy = Thy of
{axioms: term NameSpace.table,
defs: Defs.graph,
oracles: ((theory * Object.T -> term) * stamp) NameSpace.table};
fun make_thy (axioms, defs, oracles) =
Thy {axioms = axioms, defs = defs, oracles = oracles};
fun err_dup_axms dups = error ("Duplicate axiom(s): " ^ commas_quote dups);
fun err_dup_oras dups = error ("Duplicate oracle(s): " ^ commas_quote dups);
structure ThyData = TheoryDataFun
(struct
val name = "Pure/theory";
type T = thy;
val empty = make_thy (NameSpace.empty_table, Defs.empty, NameSpace.empty_table);
val copy = I;
fun extend (Thy {axioms, defs, oracles}) = make_thy (NameSpace.empty_table, defs, oracles);
fun merge pp (thy1, thy2) =
let
val Thy {axioms = _, defs = defs1, oracles = oracles1} = thy1;
val Thy {axioms = _, defs = defs2, oracles = oracles2} = thy2;
val axioms = NameSpace.empty_table;
val defs = Defs.merge pp defs1 defs2;
val oracles = NameSpace.merge_tables eq_snd (oracles1, oracles2)
handle Symtab.DUPS dups => err_dup_oras dups;
in make_thy (axioms, defs, oracles) end;
fun print _ _ = ();
end);
val init_data = ThyData.init;
fun rep_theory thy = ThyData.get thy |> (fn Thy args => args);
fun map_thy f = ThyData.map (fn (Thy {axioms, defs, oracles}) =>
make_thy (f (axioms, defs, oracles)));
fun map_axioms f = map_thy (fn (axioms, defs, oracles) => (f axioms, defs, oracles));
fun map_defs f = map_thy (fn (axioms, defs, oracles) => (axioms, f defs, oracles));
fun map_oracles f = map_thy (fn (axioms, defs, oracles) => (axioms, defs, f oracles));
(* basic operations *)
val axiom_space = #1 o #axioms o rep_theory;
val oracle_space = #1 o #oracles o rep_theory;
val axioms_of = Symtab.dest o #2 o #axioms o rep_theory;
fun all_axioms_of thy = List.concat (map axioms_of (thy :: ancestors_of thy));
val defs_of = #defs o rep_theory;
fun requires thy name what =
if Context.exists_name name thy then ()
else error ("Require theory " ^ quote name ^ " as an ancestor for " ^ what);
fun assert_super thy1 thy2 =
if subthy (thy1, thy2) then thy2
else raise THEORY ("Not a super theory", [thy1, thy2]);
(** add axioms **)
(* prepare axioms *)
fun err_in_axm name =
error ("The error(s) above occurred in axiom " ^ quote name);
fun no_vars pp tm =
(case (Term.term_vars tm, Term.term_tvars tm) of
([], []) => tm
| (ts, ixns) => error (Pretty.string_of (Pretty.block (Pretty.breaks
(Pretty.str "Illegal schematic variable(s) in term:" ::
map (Pretty.term pp) ts @ map (Pretty.typ pp o TVar) ixns)))));
fun cert_axm thy (name, raw_tm) =
let
val pp = Sign.pp thy;
val (t, T, _) = Sign.certify_term pp thy raw_tm
handle TYPE (msg, _, _) => error msg
| TERM (msg, _) => error msg;
in
Term.no_dummy_patterns t handle TERM (msg, _) => error msg;
assert (T = propT) "Term not of type prop";
(name, no_vars pp t)
end;
fun read_def_axm (thy, types, sorts) used (name, str) =
let
val ts = Syntax.read thy (Sign.is_logtype thy) (Sign.syn_of thy) propT str;
val (t, _) = Sign.infer_types (Sign.pp thy) thy types sorts used true (ts, propT);
in cert_axm thy (name, t) end
handle ERROR => err_in_axm name;
fun read_axm thy name_str = read_def_axm (thy, K NONE, K NONE) [] name_str;
fun inferT_axm thy (name, pre_tm) =
let
val pp = Sign.pp thy;
val (t, _) = Sign.infer_types pp thy (K NONE) (K NONE) [] true ([pre_tm], propT);
in (name, no_vars pp t) end
handle ERROR => err_in_axm name;
(* add_axioms(_i) *)
local
fun gen_add_axioms prep_axm raw_axms thy = thy |> map_axioms (fn axioms =>
let
val axms = map (apsnd (Term.compress_term o Logic.varify) o prep_axm thy) raw_axms;
val axioms' = NameSpace.extend_table (Sign.naming_of thy) (axioms, axms)
handle Symtab.DUPS dups => err_dup_axms dups;
in axioms' end);
in
val add_axioms = gen_add_axioms read_axm;
val add_axioms_i = gen_add_axioms cert_axm;
end;
(** add constant definitions **)
(* check_overloading *)
fun check_overloading thy overloaded (c, T) =
let
val declT =
(case Sign.const_constraint thy c of
NONE => error ("Undeclared constant " ^ quote c)
| SOME declT => declT);
val T' = Type.varifyT T;
fun message txt =
[Pretty.block [Pretty.str "Specification of constant ",
Pretty.str c, Pretty.str " ::", Pretty.brk 1, Pretty.quote (Sign.pretty_typ thy T)],
Pretty.str txt] |> Pretty.chunks |> Pretty.string_of;
in
if Sign.typ_instance thy (declT, T') then ()
else if Type.raw_instance (declT, T') then
error (Library.setmp show_sorts true
message "imposes additional sort constraints on the constant declaration")
else if overloaded then ()
else warning (message "is strictly less general than the declared type");
(c, T)
end;
(* dest_def *)
fun dest_def pp tm =
let
fun err msg = raise TERM (msg, [tm]);
val (lhs, rhs) = Logic.dest_equals (Logic.strip_imp_concl tm)
handle TERM _ => err "Not a meta-equality (==)";
val (head, args) = Term.strip_comb lhs;
val (c, T) = Term.dest_Const head
handle TERM _ => err "Head of lhs not a constant";
fun dest_free (Free (x, _)) = x
| dest_free (Const ("TYPE", Type ("itself", [TFree (x, _)]))) = x
| dest_free _ = raise Match;
val show_terms = commas_quote o map (Pretty.string_of_term pp);
val show_frees = commas_quote o map dest_free;
val show_tfrees = commas_quote o map fst;
val lhs_nofrees = filter (not o can dest_free) args;
val lhs_dups = duplicates args;
val rhs_extras = term_frees rhs |> fold (remove op =) args;
val rhs_extrasT = term_tfrees rhs |> fold (remove op =) (typ_tfrees T);
in
if not (null lhs_nofrees) then
err ("Non-variables as arguments on lhs: " ^ show_terms lhs_nofrees)
else if not (null lhs_dups) then
err ("Duplicate variables on lhs: " ^ show_frees lhs_dups)
else if not (null rhs_extras) then
err ("Extra variables on rhs: " ^ show_frees rhs_extras)
else if not (null rhs_extrasT) then
err ("Extra type variables on rhs: " ^ show_tfrees rhs_extrasT)
else if exists_Const (equal (c, T)) rhs then
err ("Constant to be defined occurs on rhs")
else ((c, T), rhs)
end;
(* check_def *)
fun check_def thy overloaded (bname, tm) defs =
let
val pp = Sign.pp thy;
fun prt_const (c, T) =
[Pretty.str c, Pretty.str " ::", Pretty.brk 1,
Pretty.quote (Pretty.typ pp (Type.freeze_type T))];
fun declared (c, _) = (c, Sign.the_const_type thy c);
val _ = no_vars pp tm;
val (const, rhs) = dest_def pp tm handle TERM (msg, _) => error msg;
val rhs_consts = fold_aterms (fn Const const => insert (op =) const | _ => I) rhs [];
val _ = check_overloading thy overloaded const;
in
defs
|> Defs.declare (declared const)
|> fold (Defs.declare o declared) rhs_consts
|> Defs.define pp const (Sign.full_name thy bname) rhs_consts
end
handle ERROR => error (Pretty.string_of (Pretty.block
[Pretty.str ("The error(s) above occurred in definition " ^ quote bname ^ ":"),
Pretty.fbrk, Pretty.quote (Pretty.term (Sign.pp thy) tm)]));
(* add_defs(_i) *)
local
fun gen_add_defs prep_axm overloaded raw_axms thy =
let val axms = map (prep_axm thy) raw_axms in
thy
|> map_defs (fold (check_def thy overloaded) axms)
|> add_axioms_i axms
end;
in
val add_defs_i = gen_add_defs cert_axm;
val add_defs = gen_add_defs read_axm;
end;
(* add_finals(_i) *)
local
fun gen_add_finals prep_term overloaded raw_terms thy =
let
val pp = Sign.pp thy;
fun finalize tm finals =
let
val _ = no_vars pp tm;
val const as (c, _) =
(case tm of Const x => x
| Free _ => error "Attempt to finalize variable (or undeclared constant)"
| _ => error "Attempt to finalize non-constant term")
|> check_overloading thy overloaded;
in finals |> Defs.declare (c, Sign.the_const_type thy c) |> Defs.finalize const end;
in thy |> map_defs (fold finalize (map (prep_term thy) raw_terms)) end;
fun read_term thy = Sign.simple_read_term thy TypeInfer.logicT;
fun cert_term thy = #1 o Sign.certify_term (Sign.pp thy) thy;
in
val add_finals = gen_add_finals read_term;
val add_finals_i = gen_add_finals cert_term;
end;
(** add oracle **)
fun add_oracle (bname, oracle) thy = thy |> map_oracles (fn oracles =>
NameSpace.extend_table (Sign.naming_of thy) (oracles, [(bname, (oracle, stamp ()))])
handle Symtab.DUPS dups => err_dup_oras dups);
end;
structure BasicTheory: BASIC_THEORY = Theory;
open BasicTheory;