# HG changeset patch
# User wenzelm
# Date 910622045 -3600
# Node ID 0acb30dd92bca8db367b4cfbfa7837aa47d616f1
# Parent  1feeadaad6a93d484990462716a339a66250c333
The global Isabelle/Isar outer syntax.

diff -r 1feeadaad6a9 -r 0acb30dd92bc src/Pure/Isar/outer_syntax.ML
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Pure/Isar/outer_syntax.ML	Mon Nov 09 15:34:05 1998 +0100
@@ -0,0 +1,191 @@
+(*  Title:      Pure/Isar/outer_syntax.ML
+    ID:         $Id$
+    Author:     Markus Wenzel, TU Muenchen
+
+The global Isabelle/Isar outer syntax.
+*)
+
+signature BASIC_OUTER_SYNTAX =
+sig
+  val print_outer_syntax: unit -> unit
+  val main: unit -> unit
+  val main_loop: unit -> unit
+  val help: unit -> unit
+end;
+
+signature OUTER_SYNTAX =
+sig
+  include BASIC_OUTER_SYNTAX
+  type token
+  type parser
+  val parser: bool -> string -> string ->
+    (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser
+  val add_keywords: string list -> unit
+  val add_parsers: parser list -> unit
+  val get_header: Position.T -> (string, 'a) Source.source -> (bstring * bstring list) option
+  val read_text: Position.T -> (string, 'a) Source.source -> Toplevel.transition list
+  val read_file: string -> Toplevel.transition list
+  val isar: Toplevel.isar
+end;
+
+structure OuterSyntax: OUTER_SYNTAX =
+struct
+
+open OuterParse;
+
+
+(** outer syntax **)
+
+(* parsers *)
+
+type token = OuterLex.token;
+type parser_fn = token list -> (Toplevel.transition -> Toplevel.transition) * token list;
+
+datatype parser =
+  Parser of string * string * bool * parser_fn;
+
+fun parser int_only name comment parse = Parser (name, comment, int_only, parse);
+
+
+(* parse command *)
+
+fun command_name cmd =
+  group "command"
+    (position (Scan.one (OuterLex.keyword_pred (is_some o cmd)) >> OuterLex.val_of));
+
+fun command_body cmd (name, _) =
+  let val (int_only, parse) = the (cmd name)
+  in !!! (Scan.prompt (name ^ "# ") (parse >> pair int_only)) end;
+
+fun command cmd =
+  $$$ ";" >> K None ||
+  command_name cmd :-- command_body cmd >> (fn ((name, pos), (int_only, f)) =>
+    Some (Toplevel.empty |> Toplevel.name name |> Toplevel.position pos |>
+      Toplevel.interactive int_only |> f));
+
+
+
+(** global syntax state **)
+
+val global_lexicon = ref Scan.empty_lexicon;
+val global_parsers = ref (Symtab.empty: (string * (bool * parser_fn)) Symtab.table);
+
+
+(* print syntax *)
+
+fun print_outer_syntax () =
+  let
+    val keywords = map implode (Scan.dest_lexicon (! global_lexicon));
+    fun pretty_cmd (name, (comment, _)) =
+      Pretty.block [Pretty.str (name ^ ":"), Pretty.brk 2, Pretty.str comment];
+    val (int_cmds, cmds) = partition (#1 o #2 o #2) (Symtab.dest (! global_parsers));
+  in
+    Pretty.writeln (Pretty.strs ("keywords:" :: map quote keywords));
+    Pretty.writeln (Pretty.big_list "general commands:" (map pretty_cmd cmds));
+    Pretty.writeln (Pretty.big_list "interactive commands:" (map pretty_cmd int_cmds))
+  end;
+
+
+(* augment syntax *)
+
+fun add_keywords keywords =
+  global_lexicon := Scan.extend_lexicon (! global_lexicon) (map Symbol.explode keywords);
+
+fun add_parser (tab, Parser (name, comment, int_only, parse)) =
+ (if is_none (Symtab.lookup (tab, name)) then ()
+  else warning ("Redefined outer syntax command " ^ quote name);
+  Symtab.update ((name, (comment, (int_only, parse))), tab));
+
+fun add_parsers parsers =
+  (global_parsers := foldl add_parser (! global_parsers, parsers);
+    add_keywords (map (fn Parser (name, _, _, _) => name) parsers));
+
+
+(* get current lexer / parser *)
+
+(*Note: the syntax for files is statically determined at the very
+  beginning; for interactive processing it may change dynamically.*)
+
+fun get_lexicon () = ! global_lexicon;
+fun get_parser () = apsome snd o curry Symtab.lookup (! global_parsers);
+
+
+
+(** read theory **)
+
+(* source *)
+
+fun no_command cmd =
+  Scan.one ((not o OuterLex.keyword_pred ((is_some o cmd) orf equal ";")) andf OuterLex.not_eof);
+
+fun recover cmd =
+  Scan.prompt "recover# " (Scan.one OuterLex.not_eof -- Scan.repeat (no_command cmd));
+
+fun source do_recover cmd src =
+  src
+  |> Source.source OuterLex.stopper (Scan.bulk (fn xs => !!! (command (cmd ())) xs))
+    (if do_recover then Some (fn xs => recover (cmd ()) xs) else None)
+  |> Source.mapfilter I;
+
+
+(* detect header *)
+
+val head_lexicon =
+  Scan.make_lexicon (map Symbol.explode ["+", ":", "=", "theory"]);
+
+val head_parser =
+  $$$ "theory" |-- !!! (name -- ($$$ "=" |-- enum "+" name --| (Scan.ahead eof || $$$ ":")));
+
+fun get_header pos src =
+  src
+  |> Symbol.source false
+  |> OuterLex.source false (K head_lexicon) pos
+  |> Source.source OuterLex.stopper (Scan.single (Scan.option head_parser)) None
+  |> (fst o the o Source.get_single);
+
+
+(* read text (including header) *)
+
+fun read_text pos src =
+  src
+  |> Symbol.source false
+  |> OuterLex.source false (K (get_lexicon ())) pos
+  |> source false (K (get_parser ()))
+  |> Source.exhaust;
+
+fun read_file name = read_text (Position.line_name 1 (quote name)) (Source.of_file name);
+
+
+(* interactive source of state transformers *)
+
+val isar =
+  Source.tty
+  |> Symbol.source true
+  |> OuterLex.source true get_lexicon (Position.line_name 1 "stdin")
+  |> source true get_parser;
+
+
+
+(** the read-eval-print loop **)
+
+fun main_loop () = (Context.reset_context (); Toplevel.loop isar);
+
+fun main () =
+ (Toplevel.set_state Toplevel.toplevel;
+  ml_prompts "ML> " "ML# ";
+  writeln ("\n\n" ^ Context.welcome ());
+  main_loop ());
+
+
+(* help *)
+
+fun help () =
+  writeln ("This is Isabelle's underlying ML system (" ^ ml_system ^ ");\n\
+    \invoke 'main_loop();' to enter the Isar loop.");
+
+
+end;
+
+
+structure BasicOuterSyntax: BASIC_OUTER_SYNTAX = OuterSyntax;
+open BasicOuterSyntax;