04-reader-reads-3.patch

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>

        * src/symtab.c, src/symtab.c (symbol_class_set)
        (symbol_user_token_number_set): New.
        * src/reader.c (parse_token_decl): Use them.
        Use a switch instead of ifs.
        Use a single argument.

Index: src/reader.c
--- src/reader.c Sun, 09 Jun 2002 16:12:55 +0200 akim
+++ src/reader.c Sun, 09 Jun 2002 16:33:10 +0200 akim
@@ -483,14 +483,12 @@
 }


-/*-------------------------------------------------------------------.
-| Parse what comes after %token or %nterm.  For %token, WHAT_IS is   |
-| token_sym and WHAT_IS_NOT is nterm_sym.  For %nterm, the arguments |
-| are reversed.                                                      |
-`-------------------------------------------------------------------*/
+/*------------------------------------------.
+| Parse what comes after %token or %nterm.  |
+`------------------------------------------*/

 static void
-parse_token_decl (symbol_class what_is, symbol_class what_is_not)
+parse_token_decl (symbol_class class)
 {
   token_t token = tok_undef;
   char *typename = NULL;
@@ -512,60 +510,40 @@
        fatal (_("Premature EOF after %s"), token_buffer);

       token = lex ();
-      if (token == tok_comma)
+      switch (token)
        {
+       case tok_comma:
          symbol = NULL;
-         continue;
-       }
-      if (token == tok_typename)
-       {
+         break;
+
+       case tok_typename:
          typename = xstrdup (token_buffer);
          symbol = NULL;
-       }
-      else if (token == tok_identifier && *symval->tag == '\"' && symbol)
-       {
-         symbol_make_alias (symbol, symval, typename);
-         symbol = NULL;
-       }
-      else if (token == tok_identifier)
-       {
-         int oldclass = symval->class;
-         symbol = symval;
-
-         if (symbol->class == what_is_not)
-           complain (_("symbol %s redefined"), symbol->tag);
-         symbol->class = what_is;
-         if (what_is == nterm_sym && oldclass != nterm_sym)
-           symbol->number = nvars++;
-         if (what_is == token_sym && symbol->number == NUMBER_UNDEFINED)
-           symbol->number = ntokens++;
+         break;

-         if (typename)
+       case tok_identifier:
+         if (*symval->tag == '\"' && symbol)
            {
-             if (symbol->type_name == NULL)
-               symbol->type_name = typename;
-             else if (strcmp (typename, symbol->type_name) != 0)
-               complain (_("type redeclaration for %s"), symbol->tag);
+             symbol_make_alias (symbol, symval, typename);
+             symbol = NULL;
            }
-       }
-      else if (symbol && token == tok_number)
-       {
-         symbol->user_token_number = numval;
-         /* User defined EOF token? */
-         if (numval == 0)
+         else
            {
-             eoftoken = symbol;
-             eoftoken->number = 0;
-             /* It is always mapped to 0, so it was already counted in
-                NTOKENS.  */
-             --ntokens;
+             symbol = symval;
+             symbol_class_set (symbol, class);
+             if (typename)
+               symbol_type_set (symbol, typename);
            }
-       }
-      else
-       {
+         break;
+
+       case tok_number:
+         symbol_user_token_number_set (symbol, numval);
+         break;
+
+       default:
          complain (_("`%s' is invalid in %s"),
                    token_buffer,
-                   (what_is == token_sym) ? "%token" : "%nterm");
+                   (class == token_sym) ? "%token" : "%nterm");
          skip_to_char ('%');
        }
     }
@@ -922,11 +900,11 @@
              break;

            case tok_token:
-             parse_token_decl (token_sym, nterm_sym);
+             parse_token_decl (token_sym);
              break;

            case tok_nterm:
-             parse_token_decl (nterm_sym, token_sym);
+             parse_token_decl (nterm_sym);
              break;

            case tok_type:
Index: src/symtab.c
--- src/symtab.c Sun, 09 Jun 2002 16:07:13 +0200 akim
+++ src/symtab.c Sun, 09 Jun 2002 16:36:28 +0200 akim
@@ -86,6 +86,50 @@
 }


+/*-------------------------------------.
+| Set the CLASS associated to SYMBOL.  |
+`-------------------------------------*/
+
+void
+symbol_class_set (symbol_t *symbol, symbol_class class)
+{
+  if (symbol->class != unknown_sym && symbol->class != class)
+    complain (_("symbol %s redefined"), symbol->tag);
+
+  if (class == nterm_sym && symbol->class != nterm_sym)
+    symbol->number = nvars++;
+  else if (class == token_sym && symbol->number == NUMBER_UNDEFINED)
+    symbol->number = ntokens++;
+
+  symbol->class = class;
+}
+
+
+/*-------------------------------------------------.
+| Set the USER_TOKEN_NUMBER associated to SYMBOL.  |
+`-------------------------------------------------*/
+
+void
+symbol_user_token_number_set (symbol_t *symbol, int user_token_number)
+{
+  assert (symbol->class == token_sym);
+
+  if (symbol->user_token_number != USER_NUMBER_UNDEFINED)
+    complain (_("redefining user token number of %s"), symbol->tag);
+
+  symbol->user_token_number = user_token_number;
+  /* User defined EOF token? */
+  if (user_token_number == 0)
+    {
+      eoftoken = symbol;
+      eoftoken->number = 0;
+      /* It is always mapped to 0, so it was already counted in
+        NTOKENS.  */
+      --ntokens;
+    }
+}
+
+
 /*------------.
 | Free THIS.  |
 `------------*/
Index: src/symtab.h
--- src/symtab.h Sun, 09 Jun 2002 16:07:13 +0200 akim
+++ src/symtab.h Sun, 09 Jun 2002 16:25:39 +0200 akim
@@ -91,6 +91,13 @@
 void symbol_precedence_set PARAMS ((symbol_t *symbol,
                                    int prec, associativity assoc));

+/* Set the CLASS associated to SYMBOL.  */
+void symbol_class_set PARAMS ((symbol_t *symbol, symbol_class class));
+
+/* Set the USER_TOKEN_NUMBER associated to SYMBOL.  */
+void symbol_user_token_number_set PARAMS ((symbol_t *symbol, int user_number));
+
+
 /* Distinguished symbols.  AXIOM is the real start symbol, that used
    by the automaton.  STARTSYMBOL is the one specified by the user.
    */