src/Pure/Syntax/syntax.ML

+(*  Title:      Pure/Syntax/syntax
+    ID:         $Id$
+    Author:     Tobias Nipkow and Markus Wenzel, TU Muenchen
+*)
+
+signature SYNTAX =
+sig
+  (* FIXME include AST0 (?) *)
+  include LEXICON0
+  include EXTENSION0
+  include TYPE_EXT0
+  include SEXTENSION1
+  include PRINTER0
+  structure Extension: EXTENSION
+  structure Pretty: PRETTY
+  local open Extension.XGram Extension.XGram.Ast in
+    type syntax
+    val print_gram: syntax -> unit
+    val print_trans: syntax -> unit
+    val print_syntax: syntax -> unit
+    val read_ast: syntax -> string * string -> ast
+    val read: syntax -> typ -> string -> term
+    val pretty_term: syntax -> term -> Pretty.T
+    val pretty_typ: syntax -> typ -> Pretty.T
+    val string_of_term: syntax -> term -> string
+    val string_of_typ: syntax -> typ -> string
+    val type_syn: syntax
+    val extend: syntax * (indexname -> sort) -> string list * string list * sext
+      -> syntax
+    val merge: syntax * syntax -> syntax
+  end
+end;
+
+functor SyntaxFun(structure Symtab: SYMTAB and TypeExt: TYPE_EXT
+  and Parser: PARSER and SExtension: SEXTENSION and Printer: PRINTER
+  sharing TypeExt.Extension.XGram = Parser.XGram = Printer.XGram
+  and TypeExt.Extension = SExtension.Extension
+  and Parser.ParseTree.Ast = Parser.XGram.Ast)(*: SYNTAX *) = (* FIXME *)
+struct
+
+structure Extension = TypeExt.Extension;
+structure XGram = Extension.XGram;
+structure Lexicon = Parser.ParseTree.Lexicon;
+open Lexicon Extension TypeExt SExtension Printer XGram XGram.Ast;
+
+
+fun lookup tab a = Symtab.lookup (tab, a);
+
+
+
+(** datatype syntax **)
+
+datatype tables =
+  Tab of {
+    gram: Parser.Gram,
+    lexicon: Lexicon,
+    const_tab: unit Symtab.table,
+    parse_ast_trtab: (ast list -> ast) Symtab.table,
+    parse_preproc: ast -> ast,
+    parse_ruletab: (ast * ast) list Symtab.table,
+    parse_postproc: ast -> ast,
+    parse_trtab: (term list -> term) Symtab.table,
+    print_trtab: (term list -> term) Symtab.table,
+    print_preproc: ast -> ast,
+    print_ruletab: (ast * ast) list Symtab.table,
+    print_postproc: ast -> ast,
+    print_tab: Printer.tab};
+
+datatype gramgraph =
+  EmptyGG |
+  ExtGG of gramgraph ref * (ext * synrules) |
+  MergeGG of gramgraph ref * gramgraph ref;
+
+datatype syntax = Syntax of gramgraph ref * tables;
+
+
+
+(*** compile syntax ***)
+
+(* ggr_to_xgram *)
+
+fun ggr_to_xgram ggr =
+  let
+    fun flatGG ggr (xg, v) =
+      if ggr mem v then (xg, v) else flatGG' ggr (xg, ggr :: v)
+    and flatGG' (ref EmptyGG) xgv = xgv
+      | flatGG' (ref (ExtGG (ggr, ext))) xgv =
+          let
+            val (xg', v') = flatGG ggr xgv
+          in
+            (Extension.extend xg' ext, v')
+          end
+      | flatGG' (ref (MergeGG (ggr1, ggr2))) xgv =
+          flatGG ggr1 (flatGG ggr2 xgv);
+  in
+    fst (flatGG ggr (Extension.empty, []))
+  end;
+
+
+(* mk_ruletab *)
+
+fun mk_ruletab rules =
+  let
+    fun add_rule (r, tab) =
+      let
+        val a = head_of_rule r
+      in
+        case lookup tab a of
+          None => Symtab.update ((a, [r]), tab)
+        | Some rs => Symtab.update ((a, r :: rs), tab)
+      end;
+  in
+    Symtab.balance (foldr add_rule (rules, Symtab.null))
+  end;
+
+
+(* make_syntax *)
+
+fun make_syntax ggr =
+  let
+    fun mk_const_tab cs =
+      Symtab.balance
+        (Symtab.st_of_alist ((map (fn c => (c, ())) cs), Symtab.null));
+
+    fun mk_trtab alst name =
+      Symtab.balance (Symtab.st_of_alist (alst, Symtab.null))
+        handle Symtab.DUPLICATE s => error ("More than one " ^ name ^ " for " ^ quote s);
+
+    fun mk_proc (Some f) = f
+      | mk_proc None = I;
+
+    fun all_strings (opl: string prod list): string list =
+        flat (map (fn Prod (_, syn, _, _) => terminals syn) opl);
+
+    fun str_to_tok (opl: string prod list, lex: Lexicon): Token prod list =
+      map
+        (fn Prod (t, syn, s, pa) =>
+          Prod (t, translate (hd o tokenize lex) syn, s, pa))
+        opl;
+
+    fun xgram_to_tables (XGram xgram) =
+      let
+        val {roots, prods, consts, parse_ast_translation, parse_preproc, parse_rules,
+          parse_postproc, parse_translation, print_translation, print_preproc,
+          print_rules, print_postproc, print_ast_translation} = xgram;
+        val lexicon = mk_lexicon (all_strings prods);
+      in
+        Tab {
+          gram = Parser.compile_xgram (roots, str_to_tok (prods, lexicon)),
+          lexicon = lexicon,
+          const_tab = mk_const_tab consts,
+          parse_ast_trtab = mk_trtab parse_ast_translation "parse ast translation",
+          parse_preproc = mk_proc parse_preproc,
+          parse_ruletab = mk_ruletab parse_rules,
+          parse_postproc = mk_proc parse_postproc,
+          parse_trtab = mk_trtab parse_translation "parse translation",
+          print_trtab = mk_trtab print_translation "print translation",
+          print_preproc = mk_proc print_preproc,
+          print_ruletab = mk_ruletab print_rules,
+          print_postproc = mk_proc print_postproc,
+          print_tab = mk_print_tab prods
+            (mk_trtab print_ast_translation "print ast translation")}
+      end;
+  in
+    Syntax (ggr, xgram_to_tables (ggr_to_xgram ggr))
+  end;
+
+
+(* add_synrules *)
+
+fun add_synrules (Tab tabs) (SynRules rules) =
+  let
+    val {gram, lexicon, const_tab, parse_ast_trtab, parse_preproc, parse_ruletab,
+      parse_postproc, parse_trtab, print_trtab, print_preproc, print_ruletab,
+      print_postproc, print_tab} = tabs;
+    val {parse_rules, print_rules} = rules;
+    val parse_rs = flat (map snd (Symtab.alist_of parse_ruletab)) @ parse_rules;
+    val print_rs = flat (map snd (Symtab.alist_of print_ruletab)) @ print_rules;
+  in
+    Tab {
+      gram = gram, lexicon = lexicon, const_tab = const_tab,
+      parse_ast_trtab = parse_ast_trtab,
+      parse_preproc = parse_preproc,
+      parse_ruletab = mk_ruletab parse_rs,
+      parse_postproc = parse_postproc,
+      parse_trtab = parse_trtab,
+      print_trtab = print_trtab,
+      print_preproc = print_preproc,
+      print_ruletab = mk_ruletab print_rs,
+      print_postproc = print_postproc,
+      print_tab = print_tab}
+  end;
+
+
+
+(*** inspect syntax ***)
+
+(* print_syntax_old *) (* FIXME remove *)
+
+fun print_syntax_old (Syntax (_, Tab {gram, lexicon, ...})) =
+  Parser.print_gram (gram, lexicon);
+
+
+
+fun xgram_of (Syntax (ggr, _)) = ggr_to_xgram ggr;
+
+fun string_of_big_list name prts =
+  Pretty.string_of (Pretty.blk (2,
+    separate Pretty.fbrk (Pretty.str name :: prts)));
+
+
+(* print_gram *)    (* FIXME check *)
+
+fun prt_gram (XGram {roots, prods, ...}) =
+  let
+    fun pretty_name name = [Pretty.str (name ^ " ="), Pretty.brk 1];
+
+    fun pretty_xsymbs (Terminal s :: xs) =
+          Pretty.str (quote s) :: Pretty.brk 1 :: pretty_xsymbs xs
+      | pretty_xsymbs (Nonterminal (s, p) :: xs) =
+          (if is_terminal s then Pretty.str s
+          else Pretty.str (s ^ "[" ^ string_of_int p ^ "]"))
+            :: Pretty.brk 1 :: pretty_xsymbs xs
+      | pretty_xsymbs (_ :: xs) = pretty_xsymbs xs
+      | pretty_xsymbs [] = [];
+
+    fun pretty_const "" = [Pretty.brk 1]
+      | pretty_const c = [Pretty.str (" => " ^ quote c), Pretty.brk 1];
+
+    fun pretty_pri p = [Pretty.str ("(" ^ string_of_int p ^ ")")];
+
+    fun pretty_prod (Prod (name, xsymbs, const, pri)) =
+      Pretty.blk (2, pretty_name name @ pretty_xsymbs xsymbs @
+        pretty_const const @ pretty_pri pri);
+  in
+    writeln (Pretty.string_of (Pretty.blk (2,
+      separate (Pretty.brk 1) (map Pretty.str ("roots:" :: roots)))));
+    writeln (string_of_big_list "prods:" (map pretty_prod prods))
+  end;
+
+
+val print_gram = prt_gram o xgram_of;
+
+
+(* print_trans *)   (* FIXME check *)
+
+fun prt_trans (XGram xgram) =
+  let
+    fun string_of_strings name strs =
+      Pretty.string_of (Pretty.blk (2,
+        separate (Pretty.brk 1) (map Pretty.str (name :: map quote strs))));
+
+    fun string_of_trs name trs = string_of_strings name (map fst trs);
+
+    fun string_of_proc name proc =
+      Pretty.string_of (Pretty.blk (2, [Pretty.str name, Pretty.brk 1,
+        Pretty.str (if is_none proc then "None" else "Some fn")]));
+
+    fun string_of_rules name rules =
+      string_of_big_list name (map pretty_rule rules);
+
+
+    val {consts, parse_ast_translation, parse_preproc, parse_rules,
+      parse_postproc, parse_translation, print_translation, print_preproc,
+      print_rules, print_postproc, print_ast_translation, ...} = xgram;
+  in
+    writeln (string_of_strings "consts:" consts);
+    writeln (string_of_trs "parse_ast_translation:" parse_ast_translation);
+    writeln (string_of_proc "parse_preproc:" parse_preproc);
+    writeln (string_of_rules "parse_rules:" parse_rules);
+    writeln (string_of_proc "parse_postproc:" parse_postproc);
+    writeln (string_of_trs "parse_translation:" parse_translation);
+    writeln (string_of_trs "print_translation:" print_translation);
+    writeln (string_of_proc "print_preproc:" print_preproc);
+    writeln (string_of_rules "print_rules:" print_rules);
+    writeln (string_of_proc "print_postproc:" print_postproc);
+    writeln (string_of_trs "print_ast_translation:" print_ast_translation)
+  end;
+
+
+val print_trans = prt_trans o xgram_of;
+
+
+(* print_syntax *)
+
+fun print_syntax syn =
+  let
+    val xgram = xgram_of syn;
+  in
+    prt_gram xgram; prt_trans xgram
+  end;
+
+
+
+(*** parsing and printing ***)
+
+(* read_ast *)
+
+fun read_ast syn (root, s) =
+  let
+    val Syntax (_, Tab {gram, lexicon, parse_ast_trtab, ...}) = syn;
+    val root = if Parser.parsable (gram, root) then root else error ("Unparsable root " ^ root) (* Extension.logic *);    (* FIXME *)
+    fun syn_err toks =
+      error ("Syntax error at\n" ^ space_implode " " (map token_to_string toks));
+  in
+    Parser.ParseTree.pt_to_ast (lookup parse_ast_trtab)
+      (Parser.parse (gram, root, tokenize lexicon s))
+        handle Parser.SYNTAX_ERR toks => syn_err toks
+  end;
+
+
+(* norm_ast *)
+
+fun norm_ast ruletab ast =
+  let
+    fun get_rules a =
+      (case lookup ruletab a of
+        Some rules => rules
+      | None => []);
+  in
+    normalize (if Symtab.is_null ruletab then None else Some get_rules) ast
+  end;
+
+
+
+(** read **)
+
+fun read (syn as Syntax (_, Tab tabs)) ty s =
+  let
+    val {parse_preproc, parse_ruletab, parse_postproc, parse_trtab, ...} = tabs;
+    val ast = read_ast syn (typ_to_nt ty, s);
+  in
+    ast_to_term (lookup parse_trtab)
+      (parse_postproc (norm_ast parse_ruletab (parse_preproc ast)))
+  end;
+
+
+
+(** pprint_ast **)
+
+val pprint_ast = Pretty.pprint o pretty_ast;
+
+
+
+(** pretty term, typ **)
+
+fun pretty_t t_to_ast pretty_t (syn as Syntax (_, Tab tabs)) t =
+  let
+    val {print_trtab, print_preproc, print_ruletab, print_postproc, print_tab, ...} = tabs;
+    val ast = t_to_ast (lookup print_trtab) t;
+  in
+    pretty_t print_tab
+      (print_postproc (norm_ast print_ruletab (print_preproc ast)))
+  end;
+
+val pretty_term = pretty_t term_to_ast pretty_term_ast;
+
+val pretty_typ = pretty_t typ_to_ast pretty_typ_ast;
+
+fun string_of_term syn t = Pretty.string_of (pretty_term syn t);
+
+fun string_of_typ syn ty = Pretty.string_of (pretty_typ syn ty);
+
+
+
+(*** build syntax ***)
+
+(* type_syn *)
+
+val type_syn = make_syntax (ref (ExtGG (ref EmptyGG, (type_ext, empty_synrules))));
+
+
+(* extend *)  (* FIXME check *)
+
+fun extend (old_syn as Syntax (ggr, _), def_sort) (roots, xconsts, sext) =
+  let
+    fun read_typ s = typ_of_term def_sort (read old_syn typeT s);
+    val ext = ext_of_sext roots xconsts read_typ sext;
+
+    fun right_rule (xpat1 |-> xpat2) = Some (xpat1, xpat2)
+      | right_rule (xpat1 <-| xpat2) = None
+      | right_rule (xpat1 <-> xpat2) = Some (xpat1, xpat2);
+
+    fun left_rule (xpat1 |-> xpat2) = None
+      | left_rule (xpat1 <-| xpat2) = Some (xpat2, xpat1)
+      | left_rule (xpat1 <-> xpat2) = Some (xpat2, xpat1);
+
+    val (tmp_syn as Syntax (_, tmp_tabs)) =
+      make_syntax (ref (ExtGG (ggr, (ext, empty_synrules))));
+    val Syntax (_, Tab {const_tab, ...}) = tmp_syn;
+
+    fun constantify (ast as (Constant _)) = ast
+      | constantify (ast as (Variable x)) =
+          if is_some (lookup const_tab x) then Constant x else ast
+      | constantify (Appl asts) = Appl (map constantify asts);
+
+    fun read_pat (r_s as (root, s)) =
+      constantify ((read_ast tmp_syn r_s)
+        handle ERROR => error ("The error above occurred in " ^ quote s));
+
+    fun read_rule (xrule as ((_, lhs_src), (_, rhs_src))) =
+      let
+        val rule as (lhs, rhs) = (pairself read_pat) xrule;
+      in
+        case rule_error rule of
+          Some msg =>
+            error ("Error in syntax translation rule: " ^ msg ^
+              "\nexternal: " ^ quote lhs_src ^ "  ->  " ^ quote rhs_src ^
+              "\ninternal: " ^ str_of_ast lhs ^ "  ->  " ^ str_of_ast rhs)
+        | None => rule
+      end;
+
+    val xrules = xrules_of sext;
+    val new_rules =
+      SynRules {
+        parse_rules = map read_rule (mapfilter right_rule xrules),
+        print_rules = map read_rule (mapfilter left_rule xrules)};
+  in
+    Syntax (ref (ExtGG (ggr, (ext, new_rules))), add_synrules tmp_tabs new_rules)
+  end;
+
+
+(* merge *)
+
+fun merge (Syntax (ggr1, _), Syntax (ggr2, _)) =
+  make_syntax (ref (MergeGG (ggr1, ggr2)));
+
+
+end;
+