src/Pure/Isar/outer_syntax.ML

improved terminator msg;

(*  Title:      Pure/Isar/outer_syntax.ML
    ID:         $Id$
    Author:     Markus Wenzel, TU Muenchen
    License:    GPL (GNU GENERAL PUBLIC LICENSE)

The global Isabelle/Isar outer syntax.
*)

signature BASIC_OUTER_SYNTAX =
sig
  val main: unit -> unit
  val loop: unit -> unit
  val sync_main: unit -> unit
  val sync_loop: unit -> unit
  val help: unit -> unit
end;

signature OUTER_SYNTAX =
sig
  include BASIC_OUTER_SYNTAX
  structure Keyword:
    sig
      val control: string
      val diag: string
      val thy_begin: string
      val thy_switch: string
      val thy_end: string
      val thy_heading: string
      val thy_decl: string
      val thy_goal: string
      val qed: string
      val qed_block: string
      val qed_global: string
      val prf_goal: string
      val prf_block: string
      val prf_chain: string
      val prf_decl: string
      val prf_asm: string
      val prf_asm_goal: string
      val prf_script: string
      val kinds: string list
    end
  type token
  type parser
  val command: string -> string -> string ->
    (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser
  val markup_command: string -> string -> string ->
    (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser
  val markup_env_command: string -> string -> string ->
    (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser
  val verbatim_command: string -> string -> string ->
    (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser
  val improper_command: string -> string -> string ->
    (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser
  val dest_keywords: unit -> string list
  val dest_parsers: unit -> (string * string * string * bool) list
  val print_outer_syntax: unit -> unit
  val print_help: Toplevel.transition -> Toplevel.transition
  val add_keywords: string list -> unit
  val add_parsers: parser list -> unit
  val theory_header: token list -> (string * string list * (string * bool) list) * token list
  val deps_thy: string -> bool -> Path.T -> string list * Path.T list
  val load_thy: string -> bool -> bool -> Path.T -> unit
  val isar: bool -> bool -> Toplevel.isar
end;

structure OuterSyntax: OUTER_SYNTAX =
struct

structure T = OuterLex;
structure P = OuterParse;


(** outer syntax **)

(* command keyword classification *)

structure Keyword =
struct
  val control = "control";
  val diag = "diag";
  val thy_begin = "theory-begin";
  val thy_switch = "theory-switch";
  val thy_end = "theory-end";
  val thy_heading = "theory-heading";
  val thy_decl = "theory-decl";
  val thy_goal = "theory-goal";
  val qed = "qed";
  val qed_block = "qed-block";
  val qed_global = "qed-global";
  val prf_goal = "proof-goal";
  val prf_block = "proof-block";
  val prf_chain = "proof-chain";
  val prf_decl = "proof-decl";
  val prf_asm = "proof-asm";
  val prf_asm_goal = "proof-asm-goal";
  val prf_script = "proof-script";

  val kinds = [control, diag, thy_begin, thy_switch, thy_end, thy_heading, thy_decl, thy_goal,
    qed, qed_block, qed_global, prf_goal, prf_block, prf_chain, prf_decl, prf_asm, prf_asm_goal,
    prf_script];
end;


(* parsers *)

type token = T.token;
type parser_fn = token list -> (Toplevel.transition -> Toplevel.transition) * token list;

datatype markup_kind = Markup | MarkupEnv | Verbatim;

datatype parser =
  Parser of string * (string * string * markup_kind option) * bool * parser_fn;

fun parser int_only markup name comment kind parse =
  Parser (name, (comment, kind, markup), int_only, parse);


(* parse command *)

local

fun command_body cmd (name, _) =
  (case cmd name of
    Some (int_only, parse) => P.!!! (Scan.prompt (name ^ "# ") (parse >> pair int_only))
  | None => sys_error ("no parser for outer syntax command " ^ quote name));

fun terminator false = Scan.succeed ()
  | terminator true = P.group "end of input" (Scan.option P.sync -- P.$$$ ";" >> K ());

in

fun command term cmd =
  P.$$$ ";" >> K None ||
  P.sync >> K None ||
  (P.position P.command :-- command_body cmd) --| terminator term
    >> (fn ((name, pos), (int_only, f)) =>
      Some (Toplevel.empty |> Toplevel.name name |> Toplevel.position pos |>
        Toplevel.interactive int_only |> f));

end;



(** global syntax state **)

local

val global_lexicons = ref (Scan.empty_lexicon, Scan.empty_lexicon);
val global_parsers =
  ref (Symtab.empty: (((string * string) * (bool * parser_fn)) * markup_kind option) Symtab.table);
val global_markups = ref ([]: (string * markup_kind) list);

fun change_lexicons f =
  let val lexs = f (! global_lexicons) in
    (case (op inter_string) (pairself Scan.dest_lexicon lexs) of
      [] => global_lexicons := lexs
    | bads => error ("Clash of outer syntax commands and keywords: " ^ commas_quote bads))
  end;

fun get_markup (ms, (name, (_, Some m))) = (name, m) :: ms
  | get_markup (ms, _) = ms;

fun make_markups () = global_markups := Symtab.foldl get_markup ([], ! global_parsers);
fun change_parsers f = (global_parsers := f (! global_parsers); make_markups ());

in


(* get current syntax *)

(*Note: the syntax for files is statically determined at the very
  beginning; for interactive processing it may change dynamically.*)

fun get_lexicons () = ! global_lexicons;
fun get_parsers () = ! global_parsers;
fun get_parser () = apsome (#2 o #1) o curry Symtab.lookup (! global_parsers);

fun lookup_markup name = assoc (! global_markups, name);
fun is_markup kind name = (case lookup_markup name of Some k => k = kind | None => false);


(* augment syntax *)

fun add_keywords keywords = change_lexicons (apfst (fn lex =>
  (Scan.extend_lexicon lex (map Symbol.explode keywords))));

fun add_parser (tab, Parser (name, (comment, kind, markup), int_only, parse)) =
 (if is_none (Symtab.lookup (tab, name)) then ()
  else warning ("Redefined outer syntax command " ^ quote name);
  Symtab.update ((name, (((comment, kind), (int_only, parse)), markup)), tab));

fun add_parsers parsers =
  (change_parsers (fn tab => foldl add_parser (tab, parsers));
    change_lexicons (apsnd (fn lex => Scan.extend_lexicon lex
      (map (fn Parser (name, _, _, _) => Symbol.explode name) parsers))));

end;


(* print syntax *)

fun dest_keywords () = Scan.dest_lexicon (#1 (get_lexicons ()));

fun dest_parsers () =
  map (fn (name, (((cmt, kind), (int_only, _)), _)) => (name, cmt, kind, int_only))
    (Symtab.dest (get_parsers ()));

fun help_outer_syntax () =
  let
    fun pretty_cmd (name, comment, _, _) =
      Pretty.block [Pretty.str (name ^ ":"), Pretty.brk 2, Pretty.str comment];
    val (int_cmds, cmds) = partition #4 (dest_parsers ());
  in
    [Pretty.strs ("syntax keywords:" :: map quote (dest_keywords ())),
      Pretty.big_list "proper commands:" (map pretty_cmd cmds),
      Pretty.big_list "improper commands (interactive-only):" (map pretty_cmd int_cmds)]
  end;

val print_outer_syntax = Pretty.writeln o Pretty.chunks o help_outer_syntax;

val print_help =
  Toplevel.keep (fn state =>
    let val opt_thy = try Toplevel.theory_of state in
      help_outer_syntax () @
      Method.help_methods opt_thy @
      Attrib.help_attributes opt_thy
      |> Pretty.chunks |> Pretty.writeln
    end);



(** read theory **)

(* special keywords *)

val headerN = "header";
val theoryN = "theory";

val theory_keyword = P.$$$ theoryN;
val header_keyword = P.$$$ headerN;
val semicolon = P.$$$ ";";


(* sources *)

local

val no_terminator =
  Scan.unless semicolon (Scan.one (T.not_sync andf T.not_eof));

val recover = Scan.prompt "recover# " (Scan.repeat no_terminator);

in

fun source term do_recover cmd src =
  src
  |> Source.source T.stopper
    (Scan.bulk (fn xs => P.!!! (command term (cmd ())) xs))
    (if do_recover then Some recover else None)
  |> Source.mapfilter I;

end;

fun token_source (src, pos) =
  src
  |> Symbol.source false
  |> T.source false (K (get_lexicons ())) pos;

fun filter_proper src =
  src
  |> Source.filter T.is_proper;


(* scan header *)

fun scan_header get_lex scan (src, pos) =
  src
  |> Symbol.source false
  |> T.source false (fn () => (get_lex (), Scan.empty_lexicon)) pos
  |> filter_proper
  |> Source.source T.stopper (Scan.single scan) None
  |> (fst o the o Source.get_single);


(* detect new/old header *)

local

val check_header_lexicon = Scan.make_lexicon [Symbol.explode headerN, Symbol.explode theoryN];
val check_header = Scan.option (header_keyword || theory_keyword);

in

fun is_old_theory src = is_none (scan_header (K check_header_lexicon) check_header src);

end;


(* deps_thy --- inspect theory header *)

local

val header_lexicon =
  Scan.make_lexicon (map Symbol.explode ["(", ")", "+", ":", ";", "=", "files", headerN, theoryN]);

val file_name =
  (P.$$$ "(" |-- P.!!! (P.name --| P.$$$ ")")) >> rpair false || P.name >> rpair true;

in

val theory_header =
  (P.name -- (P.$$$ "=" |-- P.enum1 "+" P.name) --
    Scan.optional (P.$$$ "files" |-- P.!!! (Scan.repeat1 file_name)) [] --|  P.$$$ ":")
  >> (fn ((A, Bs), files) => (A, Bs, files));

val new_header =
  header_keyword |-- (P.!!! (P.text -- Scan.option semicolon -- theory_keyword |-- theory_header))
    || theory_keyword |-- P.!!! theory_header;

val old_header =
  P.!!! (P.group "theory header"
    (P.name -- (P.$$$ "=" |-- P.name -- Scan.repeat (P.$$$ "+" |-- P.name))))
  >> (fn (A, (B, Bs)) => (A, B :: Bs, []: (string * bool) list));

fun deps_thy name ml path =
  let
    val src = Source.of_string (File.read path);
    val pos = Path.position path;
    val (name', parents, files) =
      (*unfortunately, old-style headers dynamically depend on the current lexicon*)
      if is_old_theory (src, pos) then
        scan_header ThySyn.get_lexicon (Scan.error old_header) (src, pos)
      else scan_header (K header_lexicon) (Scan.error new_header) (src, pos);

    val ml_path = ThyLoad.ml_path name;
    val ml_file = if ml andalso is_some (ThyLoad.check_file ml_path) then [ml_path] else [];
  in
    if name <> name' then
      error ("Filename " ^ quote (Path.pack path) ^
        " does not agree with theory name " ^ quote name')
    else (parents, map (Path.unpack o #1) files @ ml_file)
  end;

end;


(* present theory source *)

local

val is_improper = not o (T.is_proper orf T.is_begin_ignore orf T.is_end_ignore);
val improper = Scan.any is_improper;

val improper_keep_indent = Scan.repeat
  (Scan.unless (Scan.one T.is_indent -- Scan.one T.is_proper) (Scan.one is_improper));

val improper_end =
  (improper -- semicolon) |-- improper_keep_indent ||
  improper_keep_indent;


val ignore =
  Scan.depend (fn d => Scan.one T.is_begin_ignore >> pair (d + 1)) ||
  Scan.depend (fn 0 => Scan.fail | d => Scan.one T.is_end_ignore >> pair (d - 1)) ||
  Scan.lift (Scan.one (OuterLex.not_eof andf (not o OuterLex.is_end_ignore)));

val opt_newline = Scan.option (Scan.one T.is_newline);

val ignore_stuff =
  opt_newline -- Scan.one T.is_begin_ignore --
    P.!!!! (Scan.pass 0 (Scan.repeat ignore) -- Scan.one T.is_end_ignore -- opt_newline);

fun markup_kind k = Scan.one (T.is_kind T.Command andf is_markup k o T.val_of);

val markup = markup_kind Markup >> T.val_of;
val markup_env = markup_kind MarkupEnv >> T.val_of;
val verbatim = markup_kind Verbatim;

val present_token =
  ignore_stuff >> K None ||
  (improper |-- markup -- P.!!!! (improper |-- P.text --| improper_end) >> Present.markup_token ||
    improper |-- markup_env -- P.!!!! (improper |-- P.text --| improper_end) >> Present.markup_env_token ||
    (P.$$$ "--" >> K "cmt") -- P.!!!! (improper |-- P.text) >> Present.markup_token ||
    (improper -- verbatim) |-- P.!!!! (improper |-- P.text --| improper_end)
      >> Present.verbatim_token ||
    Scan.one T.not_eof >> Present.basic_token) >> Some;

in

(*note: lazy evaluation ahead*)

fun present_toks text pos () =
  token_source (Source.of_list (Library.untabify text), pos)
  |> Source.source T.stopper (Scan.bulk (Scan.error present_token)) None
  |> Source.mapfilter I
  |> Source.exhaust;

fun present_text text () =
  Source.exhaust (Symbol.source false (Source.of_list (Library.untabify text)));

end;


(* load_thy --- read text (including header) *)

local

fun try_ml_file name time =
  let
    val path = ThyLoad.ml_path name;
    val tr = Toplevel.imperative (fn () => ThyInfo.load_file time path);
    val tr_name = if time then "time_use" else "use";
  in
    if is_none (ThyLoad.check_file path) then ()
    else Toplevel.excursion_error [Toplevel.empty |> Toplevel.name tr_name |> tr]
  end;

fun parse_thy src_pos =
  src_pos
  |> token_source
  |> filter_proper
  |> source false false (K (get_parser ()))
  |> Source.exhaust;

fun run_thy name path =
  let
    val text = explode (File.read path);
    val src = Source.of_list text;
    val pos = Path.position path;
  in
    Present.init_theory name;
    Present.verbatim_source name (present_text text);
    if is_old_theory (src, pos) then (ThySyn.load_thy name text;
      Present.old_symbol_source name (present_text text))   (*note: text presented twice!*)
    else (Toplevel.excursion_error (parse_thy (src, pos));
      Present.token_source name (present_toks text pos))
  end;

in

fun load_thy name ml time path =
 (if time then
    timeit (fn () =>
     (writeln ("\n**** Starting theory " ^ quote name ^ " ****");
      setmp Library.timing true (run_thy name) path;
      writeln ("**** Finished theory " ^ quote name ^ " ****\n")))
  else run_thy name path;
  Context.context (ThyInfo.get_theory name);
  if ml then try_ml_file name time else ());

end;


(* interactive source of state transformers *)

fun isar term no_pos =
  Source.tty
  |> Symbol.source true
  |> T.source true get_lexicons
    (if no_pos then Position.none else Position.line_name 1 "stdin")
  |> filter_proper
  |> source term true get_parser;



(** the read-eval-print loop **)

(* main loop *)

fun gen_loop term no_pos =
 (Context.reset_context ();
  Toplevel.loop (isar term no_pos));

fun gen_main term no_pos =
 (Toplevel.set_state Toplevel.toplevel;
  writeln (Session.welcome ());
  gen_loop term no_pos);

fun main () = gen_main false false;
fun loop () = gen_loop false false;
fun sync_main () = gen_main true true;
fun sync_loop () = gen_loop true true;


(* help *)

fun help () =
  writeln ("This is Isabelle's underlying ML system (" ^ ml_system ^ ");\n\
    \invoke 'loop();' to enter the Isar loop.");


(*final declarations of this structure!*)
val command = parser false None;
val markup_command = parser false (Some Markup);
val markup_env_command = parser false (Some MarkupEnv);
val verbatim_command = parser false (Some Verbatim);
val improper_command = parser true None;


end;

(*setup theory syntax dependent operations*)
ThyLoad.deps_thy_fn := OuterSyntax.deps_thy;
ThyLoad.load_thy_fn := OuterSyntax.load_thy;
structure ThyLoad: THY_LOAD = ThyLoad;

structure BasicOuterSyntax: BASIC_OUTER_SYNTAX = OuterSyntax;
open BasicOuterSyntax;