src/Pure/Thy/thy_info.ML
author wenzelm
Tue Aug 17 22:22:36 1999 +0200 (1999-08-17)
changeset 7244 ad714526c23e
parent 7223 b0198ca65867
child 7267 96f71fb54efb
permissions -rw-r--r--
may_load_file;
use_thy etc.: warn_finished;
added begin_update_theory;
added quiet_update_thy;
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(*  Title:      Pure/Thy/thy_info.ML
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    ID:         $Id$
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    Author:     Markus Wenzel, TU Muenchen
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Theory loader database, including theory and file dependencies.
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*)
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signature BASIC_THY_INFO =
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sig
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  val theory: string -> theory
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  val theory_of_sign: Sign.sg -> theory
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  val theory_of_thm: thm -> theory
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(*val use: string -> unit*)             (*exported later*)
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  val time_use: string -> unit
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  val touch_thy: string -> unit
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  val use_thy: string -> unit
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  val update_thy: string -> unit
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  val remove_thy: string -> unit
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  val time_use_thy: string -> unit
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  val use_thy_only: string -> unit
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  val update_thy_only: string -> unit
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end;
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signature THY_INFO =
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sig
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  include BASIC_THY_INFO
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  datatype action = Update | Outdate | Remove
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  val str_of_action: action -> string
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  val add_hook: (action -> string -> unit) -> unit
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  val names: unit -> string list
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  val get_theory: string -> theory
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  val get_preds: string -> string list
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  val loaded_files: string -> (Path.T * File.info) list
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  val touch_all_thys: unit -> unit
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  val may_load_file: bool -> bool -> Path.T -> unit
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  val use_path: Path.T -> unit
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  val use: string -> unit
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  val pretend_use: string -> unit
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  val quiet_update_thy: string -> unit
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  val begin_theory: string -> string list -> (Path.T * bool) list -> theory
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  val begin_update_theory: string -> string list -> (Path.T * bool) list -> theory
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  val end_theory: theory -> theory
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  val finish: unit -> unit
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  val register_theory: theory -> unit
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end;
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structure ThyInfo: THY_INFO =
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struct
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(** theory loader actions and hooks **)
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datatype action = Update | Outdate | Remove;
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val str_of_action = fn Update => "Update" | Outdate => "Outdate" | Remove => "Remove";
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local
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  val hooks = ref ([]: (action -> string -> unit) list);
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in
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  fun add_hook f = hooks := f :: ! hooks;
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  fun perform action name = seq (fn f => (try (fn () => f action name) (); ())) (! hooks);
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end;
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(** thy database **)
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(* messages *)
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fun gen_msg txt [] = txt
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  | gen_msg txt names = txt ^ " " ^ commas_quote names;
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fun loader_msg txt names = gen_msg ("Theory loader: " ^ txt) names;
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val show_path = space_implode " via " o map quote;
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fun cycle_msg name names = loader_msg ("cyclic dependency of " ^ show_path (name :: names)) [];
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(* derived graph operations *)
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fun add_deps name parents G =
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  foldl (fn (H, parent) => Graph.add_edge_acyclic (parent, name) H) (G, parents)
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    handle Graph.CYCLES namess => error (cat_lines (map (cycle_msg name) namess));
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fun del_deps name G =
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  foldl (fn (H, parent) => Graph.del_edge (parent, name) H) (G, Graph.imm_preds G name);
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fun update_node name parents entry G =
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  add_deps name parents
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    (if can (Graph.get_node G) name then del_deps name G else Graph.new_node (name, entry) G);
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(* thy database *)
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type deps =
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  {present: bool, outdated: bool,
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    master: ThyLoad.master option, files: (Path.T * (Path.T * File.info) option) list};
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fun make_deps present outdated master files =
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  {present = present, outdated = outdated, master = master, files = files}: deps;
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fun init_deps master files = Some (make_deps false true master (map (rpair None) files));
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type thy = deps option * theory option;
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local
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  val database = ref (Graph.empty: thy Graph.T);
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in
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  fun get_thys () = ! database;
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  fun change_thys f = database := (f (! database));
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end;
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(* access thy graph *)
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fun thy_graph f x = f (get_thys ()) x;
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fun get_names () = Graph.keys (get_thys ());
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(* access thy *)
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fun lookup_thy name = Some (thy_graph Graph.get_node name) handle Graph.UNDEFINED _ => None;
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fun get_thy name =
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  (case lookup_thy name of
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    Some thy => thy
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  | None => error (loader_msg "nothing known about theory" [name]));
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fun change_thy name f = (get_thy name; change_thys (Graph.map_node name f));
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(* access deps *)
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val lookup_deps = apsome #1 o lookup_thy;
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val get_deps = #1 o get_thy;
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fun change_deps name f = change_thy name (fn (deps, x) => (f deps, x));
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fun is_finished name = is_none (get_deps name);
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fun get_files name = (case get_deps name of Some {files, ...} => files | _ => []);
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fun loaded_files name =
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  (case get_deps name of
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    Some {master = Some master, files, ...} => ThyLoad.get_thy master :: mapfilter #2 files
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  | Some {files, ...} => mapfilter #2 files
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  | None => []);
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fun get_preds name =
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  (thy_graph Graph.imm_preds name) handle Graph.UNDEFINED _ =>
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    error (loader_msg "nothing known about theory" [name]);
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(* access theory *)
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fun get_theory name =
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  (case get_thy name of
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    (_, Some theory) => theory
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  | _ => error (loader_msg "undefined theory entry for" [name]));
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val theory_of_sign = get_theory o Sign.name_of;
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val theory_of_thm = theory_of_sign o Thm.sign_of_thm;
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fun put_theory name theory = change_thy name (fn (deps, _) => (deps, Some theory));
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(** thy operations **)
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(* maintain 'outdated' flag *)
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local
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fun is_outdated name =
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  (case lookup_deps name of
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    Some (Some {outdated, ...}) => outdated
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  | _ => false);
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fun outdate_thy name =
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  if is_finished name orelse is_outdated name then ()
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  else (change_deps name (apsome (fn {present, outdated = _, master, files} =>
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    make_deps present true master files)); perform Outdate name);
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in
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fun touch_thy name =
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  if is_finished name then warning (loader_msg "tried to touch finished theory" [name])
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  else seq outdate_thy (thy_graph Graph.all_succs [name]);
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fun touch_all_thys () = seq outdate_thy (get_names ());
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end;
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(* check 'finished' state *)
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fun check_unfinished fail name =
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  if is_some (lookup_thy name) andalso is_finished name then
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    fail (loader_msg "cannot change finished theory" [name])
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  else ();
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(* may_load_file *)
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local
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fun may_run_file really path =
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  let
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    val load = ThyLoad.may_load_file really;
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    fun provide name info (deps as Some {present, outdated, master, files}) =
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          if exists (equal path o #1) files then
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            Some (make_deps present outdated master (overwrite (files, (path, Some info))))
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          else (warning (loader_msg "undeclared dependency of theory" [name] ^
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            " on file: " ^ quote (Path.pack path)); deps)
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      | provide _ _ None = None;
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  in
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    (case apsome PureThy.get_name (Context.get_context ()) of
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      None => (load path; ())
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    | Some name =>
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        if is_some (lookup_thy name) then change_deps name (provide name (load path))
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        else (load path; ()))
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  end;
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in
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fun may_load_file really time path =
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  if really andalso time then
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    let val name = Path.pack path in
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      timeit (fn () =>
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       (writeln ("\n**** Starting file " ^ quote name ^ " ****");
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        may_run_file really path;
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        writeln ("**** Finished file " ^ quote name ^ " ****\n")))
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    end
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  else may_run_file really path;
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end;
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val use_path    = may_load_file true false;
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val use         = use_path o Path.unpack;
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val time_use    = may_load_file true true o Path.unpack;
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val pretend_use = may_load_file false false o Path.unpack;
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(* load_thy *)
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fun required_by [] = ""
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  | required_by initiators = " (required by " ^ show_path (rev initiators) ^ ")";
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fun load_thy ml time initiators dir name parents =
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  let
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    val _ = if name mem_string initiators then error (cycle_msg name (rev initiators)) else ();
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    val _ = writeln ("Loading theory " ^ quote name ^ required_by initiators);
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    val _ = touch_thy name;
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    val master = ThyLoad.load_thy dir name ml time;
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    val files = get_files name;
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    val missing_files = mapfilter (fn (path, None) => Some (Path.pack path) | _ => None) files;
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  in
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    if null missing_files then ()
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    else warning (loader_msg "unresolved dependencies of theory" [name] ^
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      " on file(s): " ^ commas_quote missing_files);
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    change_deps name (fn _ => Some (make_deps true false (Some master) files));
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    perform Update name
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  end;
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(* require_thy *)
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local
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fun load_deps dir name =
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  let val (master, (parents, files)) = ThyLoad.deps_thy dir name
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  in (Some (init_deps (Some master) files), parents) end;
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fun file_current (_, None) = false
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  | file_current (path, info) = info = ThyLoad.check_file path;
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fun current_deps strict dir name =
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  (case lookup_deps name of
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    None => (false, load_deps dir name)
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  | Some deps =>
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      let val same_deps = (None, thy_graph Graph.imm_preds name) in
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        (case deps of
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          None => (true, same_deps)
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        | Some {present, outdated, master, files} =>
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            if present andalso not strict then (true, same_deps)
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            else
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              let val master' = Some (ThyLoad.check_thy dir name) in
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                if master <> master' then (false, load_deps dir name)
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                else (not outdated andalso forall file_current files, same_deps)
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              end)
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      end);
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fun require_thy ml time strict keep_strict initiators prfx (visited, str) =
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  let
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    val path = Path.expand (Path.unpack str);
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    val name = Path.pack (Path.base path);
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  in
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    if name mem_string visited then (visited, (true, name))
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    else
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      let
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        val dir = Path.append prfx (Path.dir path);
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        val req_parent =
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          require_thy true time (strict andalso keep_strict) keep_strict (name :: initiators) dir;
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        val (current, (new_deps, parents)) = current_deps strict dir name handle ERROR =>
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          error (loader_msg "the error(s) above occurred while examining theory" [name] ^
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            (if null initiators then "" else "\n" ^ required_by initiators));
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        val (visited', parent_results) = foldl_map req_parent (name :: visited, parents);
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        val result =
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          if current andalso forall #1 parent_results then true
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          else
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            ((case new_deps of
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              Some deps => change_thys (update_node name parents (deps, None))
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            | None => ());
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             load_thy ml time initiators dir name parents;
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             false);
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      in (visited', (result, name)) end
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  end;
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fun gen_use_thy req s =
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  let val (_, (_, name)) = req [] Path.current ([], s)
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  in Context.context (get_theory name) end;
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fun warn_finished f name = (check_unfinished warning name; f name);
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in
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val weak_use_thy     = gen_use_thy (require_thy true false false false);
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val quiet_update_thy = gen_use_thy (require_thy true false true true);
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val use_thy          = warn_finished (gen_use_thy (require_thy true false true false));
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val time_use_thy     = warn_finished (gen_use_thy (require_thy true true true false));
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val use_thy_only     = warn_finished (gen_use_thy (require_thy false false true false));
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val update_thy       = warn_finished (gen_use_thy (require_thy true false true true));
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val update_thy_only  = warn_finished (gen_use_thy (require_thy false false true true));
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end;
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(* remove_thy *)
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fun remove_thy name =
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  if is_finished name then error (loader_msg "cannot remove finished theory" [name])
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  else
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    let val succs = thy_graph Graph.all_succs [name] in
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      writeln (loader_msg "removing" succs);
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      seq (perform Remove) succs;
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      change_thys (Graph.del_nodes succs)
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    end;
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(* begin / end theory *)
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fun gen_begin_theory check_thy name parents paths =
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  let
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    val _ = check_unfinished error name;
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    val _ = (map Path.basic parents; seq check_thy parents);
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    val theory = PureThy.begin_theory name (map get_theory parents);
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    val _ = change_thys (update_node name parents (init_deps None [], Some theory));
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    val use_paths = mapfilter (fn (x, true) => Some x | _ => None) paths;
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  in Context.setmp (Some theory) (seq use_path) use_paths; theory end;
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   363
wenzelm@7244
   364
val begin_theory = gen_begin_theory weak_use_thy;
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val begin_update_theory = gen_begin_theory quiet_update_thy;
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wenzelm@6211
   367
fun end_theory theory =
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  let
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    val theory' = PureThy.end_theory theory;
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    val name = PureThy.get_name theory;
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  in put_theory name theory'; theory' end;
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   372
wenzelm@6211
   373
wenzelm@6666
   374
(* finish all theories *)
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wenzelm@6666
   376
fun finish () = change_thys (Graph.map_nodes (fn (_, entry) => (None, entry)));
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   377
wenzelm@6211
   378
wenzelm@6211
   379
(* register existing theories *)
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   380
wenzelm@6211
   381
fun register_theory theory =
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  let
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   383
    val name = PureThy.get_name theory;
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    val parents = Theory.parents_of theory;
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    val parent_names = map PureThy.get_name parents;
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   386
wenzelm@6211
   387
    fun err txt bads =
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   388
      error (loader_msg txt bads ^ "\n" ^ gen_msg "cannot register theory" [name]);
wenzelm@6211
   389
wenzelm@6666
   390
    val nonfinished = filter_out is_finished parent_names;
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   391
    fun get_variant (x, y_name) =
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   392
      if Theory.eq_thy (x, get_theory y_name) then None
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   393
      else Some y_name;
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    val variants = mapfilter get_variant (parents ~~ parent_names);
wenzelm@6211
   395
wenzelm@6211
   396
    fun register G =
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   397
      (Graph.new_node (name, (None, Some theory)) G
wenzelm@6211
   398
        handle Graph.DUPLICATE _ => err "duplicate theory entry" [])
wenzelm@6211
   399
      |> add_deps name parent_names;
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   400
  in
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   401
    if not (null nonfinished) then err "non-finished parent theories" nonfinished
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   402
    else if not (null variants) then err "different versions of parent theories" variants
wenzelm@7099
   403
    else (change_thys register; perform Update name)
wenzelm@6211
   404
  end;
wenzelm@6211
   405
wenzelm@6211
   406
wenzelm@6211
   407
(*final declarations of this structure*)
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   408
val theory = get_theory;
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   409
val names = get_names;
wenzelm@6211
   410
wenzelm@6211
   411
end;
wenzelm@6211
   412
wenzelm@5209
   413
structure BasicThyInfo: BASIC_THY_INFO = ThyInfo;
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   414
open BasicThyInfo;