src/Pure/theory.ML
author wenzelm
Tue Oct 28 17:31:55 1997 +0100 (1997-10-28)
changeset 4019 f9bfb914805a
parent 3996 b7548325adc4
child 4048 b9fd385981bd
permissions -rw-r--r--
added ancestors;
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(*  Title:      Pure/theory.ML
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    ID:         $Id$
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    Author:     Lawrence C Paulson and Markus Wenzel
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    Copyright   1996  University of Cambridge
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Theories.
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*)
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(*this part made pervasive*)
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signature BASIC_THEORY =
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sig
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  type theory
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  exception THEORY of string * theory list
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  val rep_theory: theory ->
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    {sign: Sign.sg,
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      axioms: term Symtab.table,
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      oracles: ((Sign.sg * exn -> term) * stamp) Symtab.table,
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      parents: theory list,
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      ancestors: theory list}
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  val sign_of: theory -> Sign.sg
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  val syn_of: theory -> Syntax.syntax
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  val parents_of: theory -> theory list
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  val ancestors_of: theory -> theory list
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  val subthy: theory * theory -> bool
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  val eq_thy: theory * theory -> bool
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  val cert_axm: Sign.sg -> string * term -> string * term
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  val read_axm: Sign.sg -> string * string -> string * term
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  val inferT_axm: Sign.sg -> string * term -> string * term
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  val merge_theories: string -> theory * theory -> theory
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end
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signature THEORY =
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sig
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  include BASIC_THEORY
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  val axiomK: string
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  val oracleK: string
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  (*theory extendsion primitives*)
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  val add_classes: (bclass * xclass list) list -> theory -> theory
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  val add_classes_i: (bclass * class list) list -> theory -> theory
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  val add_classrel: (xclass * xclass) list -> theory -> theory
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  val add_classrel_i: (class * class) list -> theory -> theory
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  val add_defsort: xsort -> theory -> theory
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  val add_defsort_i: sort -> theory -> theory
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  val add_types: (bstring * int * mixfix) list -> theory -> theory
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  val add_tyabbrs: (bstring * string list * string * mixfix) list
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    -> theory -> theory
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  val add_tyabbrs_i: (bstring * string list * typ * mixfix) list
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    -> theory -> theory
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  val add_arities: (xstring * xsort list * xsort) list -> theory -> theory
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  val add_arities_i: (string * sort list * sort) list -> theory -> theory
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  val add_consts: (bstring * string * mixfix) list -> theory -> theory
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  val add_consts_i: (bstring * typ * mixfix) list -> theory -> theory
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  val add_syntax: (bstring * string * mixfix) list -> theory -> theory
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  val add_syntax_i: (bstring * typ * mixfix) list -> theory -> theory
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  val add_modesyntax: string * bool -> (bstring * string * mixfix) list -> theory -> theory
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  val add_modesyntax_i: string * bool -> (bstring * typ * mixfix) list -> theory -> theory
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  val add_trfuns:
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    (bstring * (Syntax.ast list -> Syntax.ast)) list *
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    (bstring * (term list -> term)) list *
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    (bstring * (term list -> term)) list *
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    (bstring * (Syntax.ast list -> Syntax.ast)) list -> theory -> theory
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  val add_trfunsT:
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    (bstring * (typ -> term list -> term)) list -> theory -> theory
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  val add_tokentrfuns:
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    (string * string * (string -> string * int)) list -> theory -> theory
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  val add_trrules: (string * string) Syntax.trrule list -> theory -> theory
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  val add_trrules_i: Syntax.ast Syntax.trrule list -> theory -> theory
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  val add_axioms: (bstring * string) list -> theory -> theory
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  val add_axioms_i: (bstring * term) list -> theory -> theory
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  val add_oracle: bstring * (Sign.sg * exn -> term) -> theory -> theory
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  val add_defs: (bstring * string) list -> theory -> theory
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  val add_defs_i: (bstring * term) list -> theory -> theory
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  val add_path: string -> theory -> theory
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  val add_space: string * string list -> theory -> theory
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  val add_name: string -> theory -> theory
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  val init_data: string -> exn * (exn -> exn) * (exn * exn -> exn) * (exn -> unit)
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    -> theory -> theory
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  val get_data: theory -> string -> exn
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  val put_data: string * exn -> theory -> theory
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  val prep_ext: theory -> theory
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  val prep_ext_merge: theory list -> theory
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  val pre_pure: theory
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end;
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structure Theory: THEORY =
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struct
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(** datatype theory **)
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datatype theory =
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  Theory of {
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    sign: Sign.sg,
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    axioms: term Symtab.table,
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    oracles: ((Sign.sg * exn -> term) * stamp) Symtab.table,
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    parents: theory list,
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    ancestors: theory list};
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fun make_thy sign axms oras parents ancestors =
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  Theory {sign = sign, axioms = axms, oracles = oras,
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    parents = parents, ancestors = ancestors};
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fun rep_theory (Theory args) = args;
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val sign_of = #sign o rep_theory;
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val syn_of = #syn o Sign.rep_sg o sign_of;
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val parents_of = #parents o rep_theory;
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val ancestors_of = #ancestors o rep_theory;
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(*errors involving theories*)
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exception THEORY of string * theory list;
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(*compare theories*)
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val subthy = Sign.subsig o pairself sign_of;
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val eq_thy = Sign.eq_sg o pairself sign_of;
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(* partial Pure theory *)
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val pre_pure = make_thy Sign.pre_pure Symtab.null Symtab.null [] [];
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(** extend theory **)
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(*name space kinds*)
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val axiomK = "axiom";
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val oracleK = "oracle";
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(* extend logical part of a theory *)
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fun err_dup_axms names =
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  error ("Duplicate axiom name(s) " ^ commas_quote names);
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fun err_dup_oras names =
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  error ("Duplicate oracles " ^ commas_quote names);
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fun ext_thy thy sign' new_axms new_oras =
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  let
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    val Theory {sign, axioms, oracles, parents, ancestors} = thy;
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    val draft = Sign.is_draft sign;
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    val axioms' =
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      Symtab.extend_new (if draft then axioms else Symtab.null, new_axms)
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        handle Symtab.DUPS names => err_dup_axms names;
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    val oracles' =
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      Symtab.extend_new (oracles, new_oras)
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        handle Symtab.DUPS names => err_dup_oras names;
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    val (parents', ancestors') =
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      if draft then (parents, ancestors) else ([thy], thy :: ancestors);
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  in
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    make_thy sign' axioms' oracles' parents' ancestors'
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  end;
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(* extend signature of a theory *)
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fun ext_sg extfun decls (thy as Theory {sign, ...}) =
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  ext_thy thy (extfun decls sign) [] [];
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val add_classes      = ext_sg Sign.add_classes;
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val add_classes_i    = ext_sg Sign.add_classes_i;
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val add_classrel     = ext_sg Sign.add_classrel;
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val add_classrel_i   = ext_sg Sign.add_classrel_i;
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val add_defsort      = ext_sg Sign.add_defsort;
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val add_defsort_i    = ext_sg Sign.add_defsort_i;
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val add_types        = ext_sg Sign.add_types;
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val add_tyabbrs      = ext_sg Sign.add_tyabbrs;
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val add_tyabbrs_i    = ext_sg Sign.add_tyabbrs_i;
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val add_arities      = ext_sg Sign.add_arities;
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val add_arities_i    = ext_sg Sign.add_arities_i;
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val add_consts       = ext_sg Sign.add_consts;
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val add_consts_i     = ext_sg Sign.add_consts_i;
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val add_syntax       = ext_sg Sign.add_syntax;
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val add_syntax_i     = ext_sg Sign.add_syntax_i;
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val add_modesyntax   = curry (ext_sg Sign.add_modesyntax);
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val add_modesyntax_i = curry (ext_sg Sign.add_modesyntax_i);
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val add_trfuns       = ext_sg Sign.add_trfuns;
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val add_trfunsT      = ext_sg Sign.add_trfunsT;
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val add_tokentrfuns  = ext_sg Sign.add_tokentrfuns;
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val add_trrules      = ext_sg Sign.add_trrules;
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val add_trrules_i    = ext_sg Sign.add_trrules_i;
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val add_path         = ext_sg Sign.add_path;
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val add_space        = ext_sg Sign.add_space;
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val add_name         = ext_sg Sign.add_name;
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val prep_ext         = ext_sg (K Sign.prep_ext) ();
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(** add axioms **)
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(* prepare axioms *)
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fun err_in_axm name =
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  error ("The error(s) above occurred in axiom " ^ quote name);
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fun no_vars tm =
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  if null (term_vars tm) andalso null (term_tvars tm) then tm
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  else error "Illegal schematic variable(s) in term";
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fun cert_axm sg (name, raw_tm) =
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  let
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    val (t, T, _) = Sign.certify_term sg raw_tm
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      handle TYPE (msg, _, _) => error msg
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           | TERM (msg, _) => error msg;
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  in
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    assert (T = propT) "Term not of type prop";
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    (name, no_vars t)
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  end
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  handle ERROR => err_in_axm name;
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(*Some duplication of code with read_def_cterm*)
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fun read_axm sg (name, str) = 
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  let
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    val ts = Syntax.read (#syn (Sign.rep_sg sg)) propT str;
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    val (_, t, _) =
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          Sign.infer_types sg (K None) (K None) [] true (ts, propT);
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  in cert_axm sg (name,t) end
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  handle ERROR => err_in_axm name;
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fun inferT_axm sg (name, pre_tm) =
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  let
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    val (_, t, _) =
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      Sign.infer_types sg (K None) (K None) [] true ([pre_tm], propT);
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  in (name, no_vars t) end
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  handle ERROR => err_in_axm name;
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(* extend axioms of a theory *)
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fun ext_axms prep_axm raw_axms (thy as Theory {sign, ...}) =
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  let
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    val raw_axms' = map (apfst (Sign.full_name sign)) raw_axms;
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    val axioms =
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      map (apsnd (Term.compress_term o Logic.varify) o prep_axm sign) raw_axms';
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    val sign' = Sign.add_space (axiomK, map fst axioms) sign;
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  in
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    ext_thy thy sign' axioms []
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  end;
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val add_axioms = ext_axms read_axm;
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val add_axioms_i = ext_axms cert_axm;
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(* add oracle **)
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fun add_oracle (raw_name, oracle) (thy as Theory {sign, ...}) =
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  let
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    val name = Sign.full_name sign raw_name;
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    val sign' = Sign.add_space (oracleK, [name]) sign;
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  in
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    ext_thy thy sign' [] [(name, (oracle, stamp ()))]
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  end;
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(** add constant definitions **)
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(* all_axioms_of *)
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(*results may contain duplicates!*)
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fun all_axioms_of thy =
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  flat (map (Symtab.dest o #axioms o rep_theory) (thy :: ancestors_of thy));
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(* clash_types, clash_consts *)
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(*check if types have common instance (ignoring sorts)*)
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fun clash_types ty1 ty2 =
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  let
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    val ty1' = Type.varifyT ty1;
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    val ty2' = incr_tvar (maxidx_of_typ ty1' + 1) (Type.varifyT ty2);
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  in
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    Type.raw_unify (ty1', ty2')
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  end;
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fun clash_consts (c1, ty1) (c2, ty2) =
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  c1 = c2 andalso clash_types ty1 ty2;
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(* clash_defns *)
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fun clash_defn c_ty (name, tm) =
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  let val (c, ty') = dest_Const (head_of (fst (Logic.dest_equals tm))) in
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    if clash_consts c_ty (c, ty') then Some (name, ty') else None
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  end handle TERM _ => None;
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fun clash_defns c_ty axms =
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  distinct (mapfilter (clash_defn c_ty) axms);
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(* dest_defn *)
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fun dest_defn tm =
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  let
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    fun err msg = raise TERM (msg, [tm]);
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    val (lhs, rhs) = Logic.dest_equals (Logic.strip_imp_concl tm)
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      handle TERM _ => err "Not a meta-equality (==)";
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    val (head, args) = strip_comb lhs;
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    val (c, ty) = dest_Const head
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      handle TERM _ => err "Head of lhs not a constant";
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    fun occs_const (Const c_ty') = (c_ty' = (c, ty))
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      | occs_const (Abs (_, _, t)) = occs_const t
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      | occs_const (t $ u) = occs_const t orelse occs_const u
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      | occs_const _ = false;
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    val show_frees = commas_quote o map (fst o dest_Free);
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    val show_tfrees = commas_quote o map fst;
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    val lhs_dups = duplicates args;
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    val rhs_extras = gen_rems (op =) (term_frees rhs, args);
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    val rhs_extrasT = gen_rems (op =) (term_tfrees rhs, typ_tfrees ty);
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  in
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    if not (forall is_Free args) then
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      err "Arguments (on lhs) must be variables"
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    else if not (null lhs_dups) then
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      err ("Duplicate variables on lhs: " ^ show_frees lhs_dups)
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    else if not (null rhs_extras) then
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      err ("Extra variables on rhs: " ^ show_frees rhs_extras)
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    else if not (null rhs_extrasT) then
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      err ("Extra type variables on rhs: " ^ show_tfrees rhs_extrasT)
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    else if occs_const rhs then
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      err ("Constant to be defined occurs on rhs")
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    else (c, ty)
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  end;
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(* check_defn *)
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fun err_in_defn sg name msg =
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  (writeln msg; error ("The error(s) above occurred in definition " ^
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    quote (Sign.full_name sg name)));
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fun check_defn sign (axms, (name, tm)) =
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  let
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    fun show_const (c, ty) = quote (Pretty.string_of (Pretty.block
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      [Pretty.str (c ^ " ::"), Pretty.brk 1, Sign.pretty_typ sign ty]));
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   344
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    fun show_defn c (dfn, ty') = show_const (c, ty') ^ " in " ^ dfn;
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    fun show_defns c = cat_lines o map (show_defn c);
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    val (c, ty) = dest_defn tm
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      handle TERM (msg, _) => err_in_defn sign name msg;
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    val defns = clash_defns (c, ty) axms;
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  in
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    if not (null defns) then
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      err_in_defn sign name ("Definition of " ^ show_const (c, ty) ^
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        "\nclashes with " ^ show_defns c defns)
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   355
    else (name, tm) :: axms
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   356
  end;
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   358
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   359
(* add_defs *)
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fun ext_defns prep_axm raw_axms thy =
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   362
  let
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    val axms = map (prep_axm (sign_of thy)) raw_axms;
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    val all_axms = all_axioms_of thy;
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  in
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    foldl (check_defn (sign_of thy)) (all_axms, axms);
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    add_axioms_i axms thy
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   368
  end;
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   370
val add_defs_i = ext_defns cert_axm;
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val add_defs = ext_defns read_axm;
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   372
wenzelm@3767
   373
wenzelm@3878
   374
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   375
(** additional theory data **)
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   376
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   377
val init_data = curry (ext_sg Sign.init_data);
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   378
val get_data = Sign.get_data o sign_of;
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   379
val put_data = ext_sg Sign.put_data;
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   380
wenzelm@3865
   381
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   382
wenzelm@4019
   383
(** merge theories **)		(*exception ERROR*)
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   384
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   385
fun merge_sign (sg, thy) =
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   386
  Sign.merge (sg, sign_of thy) handle TERM (msg, _) => error msg;
paulson@1526
   387
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   388
(*merge list of theories from left to right, preparing extend*)
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   389
fun prep_ext_merge thys =
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   390
  if null thys then
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   391
    error "Merge: no parent theories"
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   392
  else if exists (Sign.is_draft o sign_of) thys then
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   393
    error "Attempt to merge draft theories"
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   394
  else
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   395
    let
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   396
      val sign' =
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   397
        foldl merge_sign (sign_of (hd thys), tl thys)
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   398
        |> Sign.prep_ext
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   399
        |> Sign.add_path "/";
wenzelm@3814
   400
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   401
      val axioms' = Symtab.null;
wenzelm@4019
   402
wenzelm@3996
   403
      fun eq_ora ((_, (_, s1: stamp)), (_, (_, s2))) = s1 = s2;
wenzelm@3996
   404
      val oracles' =
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   405
        Symtab.make (gen_distinct eq_ora
wenzelm@3996
   406
          (flat (map (Symtab.dest o #oracles o rep_theory) thys)))
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   407
        handle Symtab.DUPS names => err_dup_oras names;
wenzelm@4019
   408
wenzelm@4019
   409
      val parents' = gen_distinct eq_thy thys;
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   410
      val ancestors' =
wenzelm@4019
   411
        gen_distinct eq_thy (parents' @ flat (map ancestors_of thys));
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   412
    in
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   413
      make_thy sign' axioms' oracles' parents' ancestors'
wenzelm@3996
   414
    end;
paulson@1526
   415
wenzelm@3885
   416
fun merge_theories name (thy1, thy2) =
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   417
  prep_ext_merge [thy1, thy2]
wenzelm@3885
   418
  |> add_name name;
wenzelm@3885
   419
wenzelm@3885
   420
paulson@1526
   421
end;
paulson@1526
   422
wenzelm@3767
   423
structure BasicTheory: BASIC_THEORY = Theory;
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   424
open BasicTheory;