src/Pure/Syntax/syntax.ML
changeset 42223 098c86e53153
parent 42217 1a2a53d03c31
child 42224 578a51fae383
--- a/src/Pure/Syntax/syntax.ML	Mon Apr 04 23:52:56 2011 +0200
+++ b/src/Pure/Syntax/syntax.ML	Tue Apr 05 13:07:40 2011 +0200
@@ -116,13 +116,13 @@
   val ambiguity_level_raw: Config.raw
   val ambiguity_level: int Config.T
   val ambiguity_limit: int Config.T
-  val standard_parse_term: (term -> string option) ->
+  val standard_parse_sort: Proof.context -> type_context -> syntax ->
+    Symbol_Pos.T list * Position.T -> sort
+  val standard_parse_typ: Proof.context -> type_context -> syntax ->
+    ((indexname * sort) list -> indexname -> sort) -> Symbol_Pos.T list * Position.T -> typ
+  val standard_parse_term: (term -> term Exn.result) ->
     Proof.context -> type_context -> term_context -> syntax ->
     string -> Symbol_Pos.T list * Position.T -> term
-  val standard_parse_typ: Proof.context -> type_context -> syntax ->
-    ((indexname * sort) list -> indexname -> sort) -> Symbol_Pos.T list * Position.T -> typ
-  val standard_parse_sort: Proof.context -> type_context -> syntax ->
-    Symbol_Pos.T list * Position.T -> sort
   datatype 'a trrule =
     Parse_Rule of 'a * 'a |
     Print_Rule of 'a * 'a |
@@ -130,13 +130,13 @@
   val map_trrule: ('a -> 'b) -> 'a trrule -> 'b trrule
   val is_const: syntax -> string -> bool
   val read_rule_pattern: Proof.context -> type_context -> syntax -> string * string -> ast
+  val standard_unparse_sort: {extern_class: string -> xstring} ->
+    Proof.context -> syntax -> sort -> Pretty.T
+  val standard_unparse_typ: {extern_class: string -> xstring, extern_type: string -> xstring} ->
+    Proof.context -> syntax -> typ -> Pretty.T
   val standard_unparse_term: {structs: string list, fixes: string list} ->
     {extern_class: string -> xstring, extern_type: string -> xstring,
       extern_const: string -> xstring} -> Proof.context -> syntax -> bool -> term -> Pretty.T
-  val standard_unparse_typ: {extern_class: string -> xstring, extern_type: string -> xstring} ->
-    Proof.context -> syntax -> typ -> Pretty.T
-  val standard_unparse_sort: {extern_class: string -> xstring} ->
-    Proof.context -> syntax -> sort -> Pretty.T
   val update_trfuns:
     (string * ((ast list -> ast) * stamp)) list *
     (string * ((term list -> term) * stamp)) list *
@@ -686,17 +686,9 @@
 
 
 
-(** read **)
+(** read **)  (* FIXME rename!? *)
 
-fun some_results f xs =
-  let
-    val exn_results = map (Exn.interruptible_capture f) xs;
-    val exns = map_filter Exn.get_exn exn_results;
-    val results = map_filter Exn.get_result exn_results;
-  in (case (results, exns) of ([], exn :: _) => reraise exn | _ => results) end;
-
-
-(* read_ast *)
+(* configuration options *)
 
 val positions_raw = Config.declare "syntax_positions" (fn _ => Config.Bool true);
 val positions = Config.bool positions_raw;
@@ -712,6 +704,23 @@
 
 fun ambiguity_msg pos = "Parse error: ambiguous syntax" ^ Position.str_of pos;
 
+
+(* results *)
+
+fun proper_results results = map_filter (fn (y, Exn.Result x) => SOME (y, x) | _ => NONE) results;
+fun failed_results results = map_filter (fn (y, Exn.Exn e) => SOME (y, e) | _ => NONE) results;
+
+fun report ctxt = List.app (fn (pos, m) => Context_Position.report ctxt pos m);
+
+fun report_result ctxt pos results =
+  (case (proper_results results, failed_results results) of
+    ([], (reports, exn) :: _) => (report ctxt reports; reraise exn)
+  | ([(reports, x)], _) => (report ctxt reports; x)
+  | _ => error (ambiguity_msg pos));
+
+
+(* read_asts *)
+
 fun read_asts ctxt type_ctxt (Syntax (tabs, _)) raw root (syms, pos) =
   let
     val {lexicon, gram, parse_ast_trtab, ...} = tabs;
@@ -736,84 +745,87 @@
             map (Pretty.string_of o Parser.pretty_parsetree) (take limit pts))));
 
     val constrain_pos = not raw andalso Config.get ctxt positions;
-  in
-    some_results
-      (Syn_Trans.parsetree_to_ast ctxt type_ctxt constrain_pos (lookup_tr parse_ast_trtab)) pts
-  end;
+    val parsetree_to_ast =
+      Syn_Trans.parsetree_to_ast ctxt type_ctxt constrain_pos (lookup_tr parse_ast_trtab);
+  in map parsetree_to_ast pts end;
 
 
-(* read *)
+(* read_raw *)
 
-fun read ctxt type_ctxt (syn as Syntax (tabs, _)) root inp =
-  let val {parse_ruletab, parse_trtab, ...} = tabs in
-    read_asts ctxt type_ctxt syn false root inp
-    |> map (apsnd (Ast.normalize ctxt (Symtab.lookup_list parse_ruletab)))
-    |> some_results (apsnd (Syn_Trans.ast_to_term ctxt (lookup_tr parse_trtab)))
+fun read_raw ctxt type_ctxt (syn as Syntax (tabs, _)) root input =
+  let
+    val {parse_ruletab, parse_trtab, ...} = tabs;
+    val norm = Ast.normalize ctxt (Symtab.lookup_list parse_ruletab);
+    val ast_to_term = Syn_Trans.ast_to_term ctxt (lookup_tr parse_trtab);
+  in
+    read_asts ctxt type_ctxt syn false root input
+    |> (map o apsnd o Exn.maps_result) (norm #> Exn.interruptible_capture ast_to_term)
   end;
 
 
-(* read terms *)
-
-fun report_result ctxt (reports, res) =
-  (List.app (fn (pos, m) => Context_Position.report ctxt pos m) reports; res);
-
-(*brute-force disambiguation via type-inference*)
-fun disambig ctxt _ [arg] = report_result ctxt arg
-  | disambig ctxt check args =
-      let
-        val level = Config.get ctxt ambiguity_level;
-        val limit = Config.get ctxt ambiguity_limit;
-
-        val ambiguity = length args;
-        fun ambig_msg () =
-          if ambiguity > 1 andalso ambiguity <= level then
-            "Got more than one parse tree.\n\
-            \Retry with smaller syntax_ambiguity_level for more information."
-          else "";
+(* read sorts *)
 
-        val errs = Par_List.map_name "Syntax.disambig" (check o snd) args;
-        val results = map_filter (fn (arg, NONE) => SOME arg | _ => NONE) (args ~~ errs);
-        val len = length results;
-
-        val show_term = string_of_term (Config.put Printer.show_brackets true ctxt);
-      in
-        if null results then cat_error (ambig_msg ()) (cat_lines (map_filter I errs))
-        else if len = 1 then
-          (if ambiguity > level then
-            Context_Position.if_visible ctxt warning
-              "Fortunately, only one parse tree is type correct.\n\
-              \You may still want to disambiguate your grammar or your input."
-          else (); report_result ctxt (hd results))
-        else cat_error (ambig_msg ()) (cat_lines
-          (("Ambiguous input, " ^ string_of_int len ^ " terms are type correct" ^
-            (if len <= limit then "" else " (" ^ string_of_int limit ^ " displayed)") ^ ":") ::
-            map (show_term o snd) (take limit results)))
-      end;
-
-fun standard_parse_term check ctxt type_ctxt term_ctxt syn root (syms, pos) =
-  read ctxt type_ctxt syn root (syms, pos)
-  |> map (Type_Ext.decode_term term_ctxt)
-  |> disambig ctxt check;
+fun standard_parse_sort ctxt type_ctxt syn (syms, pos) =
+  read_raw ctxt type_ctxt syn (Syn_Ext.typ_to_nonterm Type_Ext.sortT) (syms, pos)
+  |> report_result ctxt pos
+  |> Type_Ext.sort_of_term;
 
 
 (* read types *)
 
 fun standard_parse_typ ctxt type_ctxt syn get_sort (syms, pos) =
-  (case read ctxt type_ctxt syn (Syn_Ext.typ_to_nonterm Syn_Ext.typeT) (syms, pos) of
-    [res] =>
-      let val t = report_result ctxt res
-      in Type_Ext.typ_of_term (get_sort (Type_Ext.term_sorts t)) t end
-  | _ => error (ambiguity_msg pos));
+  read_raw ctxt type_ctxt syn (Syn_Ext.typ_to_nonterm Syn_Ext.typeT) (syms, pos)
+  |> report_result ctxt pos
+  |> (fn t => Type_Ext.typ_of_term (get_sort (Type_Ext.term_sorts t)) t);
 
 
-(* read sorts *)
+(* read terms -- brute-force disambiguation via type-inference *)
+
+fun standard_parse_term check ctxt type_ctxt term_ctxt syn root (syms, pos) =
+  let
+    val results =
+      read_raw ctxt type_ctxt syn root (syms, pos)
+      |> map (Type_Ext.decode_term term_ctxt);
+
+    val level = Config.get ctxt ambiguity_level;
+    val limit = Config.get ctxt ambiguity_limit;
+
+    val ambiguity = length (proper_results results);
+
+    fun ambig_msg () =
+      if ambiguity > 1 andalso ambiguity <= level then
+        "Got more than one parse tree.\n\
+        \Retry with smaller syntax_ambiguity_level for more information."
+      else "";
 
-fun standard_parse_sort ctxt type_ctxt syn (syms, pos) =
-  (case read ctxt type_ctxt syn (Syn_Ext.typ_to_nonterm Type_Ext.sortT) (syms, pos) of
-    [res] =>
-      let val t = report_result ctxt res
-      in Type_Ext.sort_of_term t end
-  | _ => error (ambiguity_msg pos));
+    val results' =
+      if ambiguity > 1 then
+        (Par_List.map_name "Syntax.disambig" o apsnd o Exn.maps_result) check results
+      else results;
+    val reports' = fst (hd results');
+
+    val errs = map snd (failed_results results');
+    val checked = map snd (proper_results results');
+    val len = length checked;
+
+    val show_term = string_of_term (Config.put Printer.show_brackets true ctxt);
+  in
+    if len = 0 then
+      report_result ctxt pos
+        [(reports', Exn.Exn (Exn.EXCEPTIONS (ERROR (ambig_msg ()) :: errs)))]
+    else if len = 1 then
+      (if ambiguity > level then
+        Context_Position.if_visible ctxt warning
+          "Fortunately, only one parse tree is type correct.\n\
+          \You may still want to disambiguate your grammar or your input."
+      else (); report_result ctxt pos results')
+    else
+      report_result ctxt pos
+        [(reports', Exn.Exn (ERROR (cat_lines (ambig_msg () ::
+          (("Ambiguous input, " ^ string_of_int len ^ " terms are type correct" ^
+            (if len <= limit then "" else " (" ^ string_of_int limit ^ " displayed)") ^ ":") ::
+            map show_term (take limit checked))))))]
+  end;
 
 
 
@@ -874,11 +886,9 @@
 
     val (syms, pos) = read_token str;
   in
-    (case read_asts ctxt type_ctxt syn true root (syms, pos) of
-      [res] =>
-        let val ast = report_result ctxt res
-        in constify ast end
-    | _ => error (ambiguity_msg pos))
+    read_asts ctxt type_ctxt syn true root (syms, pos)
+    |> report_result ctxt pos
+    |> constify
   end;
 
 
@@ -899,16 +909,16 @@
 
 in
 
-fun standard_unparse_term idents extern =
-  unparse_t (Printer.term_to_ast idents) (Printer.pretty_term_ast extern) Markup.term;
+fun standard_unparse_sort {extern_class} ctxt syn =
+  unparse_t (K Printer.sort_to_ast)
+    (Printer.pretty_typ_ast {extern_class = extern_class, extern_type = I})
+    Markup.sort ctxt syn false;
 
 fun standard_unparse_typ extern ctxt syn =
   unparse_t (K Printer.typ_to_ast) (Printer.pretty_typ_ast extern) Markup.typ ctxt syn false;
 
-fun standard_unparse_sort {extern_class} ctxt syn =
-  unparse_t (K Printer.sort_to_ast)
-    (Printer.pretty_typ_ast {extern_class = extern_class, extern_type = I})
-    Markup.sort ctxt syn false;
+fun standard_unparse_term idents extern =
+  unparse_t (Printer.term_to_ast idents) (Printer.pretty_term_ast extern) Markup.term;
 
 end;