* src/gram.h, src/gram.c (nitems): Remove, it is an alias of

[bison.git] / src / gram.h

diff --git a/src/gram.h b/src/gram.h
index 75f4653ea7bab1a2ead7e3408c449da10b4d5952..cc8e7ff9445011b9560f9f205508757dd21f6033 100644 (file)
--- a/src/gram.h
+++ b/src/gram.h
@@ -1,5 +1,6 @@
 /* Data definitions for internal representation of bison's input,
-   Copyright 1984, 1986, 1989, 1992, 2001  Free Software Foundation, Inc.
+   Copyright (C) 1984, 1986, 1989, 1992, 2001, 2002
+   Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -53,23 +54,24 @@
 
    RULES is an array of struct rule_s, which members are:
 
-   RULES[R].lhs -- the symbol number of the left hand side of rule R.
-   If -1, the rule has been thrown out by reduce.c and should be
-   ignored.
+   RULES[R].lhs -- the symbol of the left hand side of rule R.
 
    RULES[R].rhs -- the index in RITEM of the beginning of the portion
    for rule R.
 
-   RULES[R].prec -- the precedence level of R.
+   RULES[R].prec -- the symbol providing the precedence level of R.
 
-   RULES[R].precsym -- the symbol-number of the symbol in %prec for R
-   (if any).
+   RULES[R].precsym -- the symbol attached (via %prec) to give its
+   precedence to R.  Of course, if set, it is equal to `prec', but we
+   need to distinguish one from the other when reducing: a symbol used
+   in a %prec is not useless.
 
    RULES[R].assoc -- the associativity of R.
 
    RULES[R].line -- the line where R was defined.
 
-   RULES[R].useful -- TRUE iff the rule is used.
+   RULES[R].useful -- TRUE iff the rule is used (i.e., FALSE if thrown
+   away by reduce).
 
    The right hand side is stored as symbol numbers in a portion of
    RITEM.
@@ -80,7 +82,7 @@
    says which rule it is for.
 
    The portions of RITEM come in order of increasing rule number and
-   are followed by an element which is zero to mark the end.  nitems
+   are followed by an element which is zero to mark the end.  nritems
    is the total length of ritem, not counting the final zero.  Each
    element of RITEM is called an "item" and its index in RITEM is an
    item number.
@@ -97,11 +99,11 @@
 
    Associativities are recorded similarly in SYMBOLS[I]->assoc.  */
 
+#include "symtab.h"
 
 #define        ISTOKEN(s)      ((s) < ntokens)
 #define        ISVAR(s)        ((s) >= ntokens)
 
-extern int nitems;
 extern int nrules;
 extern int nsyms;
 extern int ntokens;
@@ -112,22 +114,25 @@ extern int nritems;
 
 extern int start_symbol;
 
-/* Associativity values for tokens and rules.  */
-typedef enum
+typedef struct rule_s
 {
-  right_assoc,
-  left_assoc,
-  non_assoc
-} associativity;
+  /* The number of the rule in the source.  It is usually the index in
+     RULES too, except if there are useless rules.  */
+  short user_number;
 
+  /* The index in RULES.  Usually the rule number in the source,
+     except if some rules are useless.  */
+  short number;
+
+  symbol_t *lhs;
+  short *rhs;
+
+  /* This symbol provides both the associativity, and the precedence. */
+  symbol_t *prec;
+
+  /* This symbol was attached to the rule via %prec. */
+  symbol_t *precsym;
 
-typedef struct rule_s
-{
-  short lhs;
-  short rhs;
-  short prec;
-  short precsym;
-  associativity assoc;
   short line;
   bool useful;
 
@@ -141,7 +146,7 @@ typedef struct rule_s
 extern struct rule_s *rules;
 
 /* Table of the symbols, indexed by the symbol number. */
-extern struct bucket **symbols;
+extern symbol_t **symbols;
 
 /* token translation table: indexed by a token number as returned by
    the user's yylex routine, it yields the internal token number used
@@ -165,6 +170,8 @@ extern int pure_parser;
 
 extern int error_token_number;
 
+/* Report the length of the RHS. */
+int rule_rhs_length PARAMS ((rule_t *rule));
 
 /* Dump RITEM for traces. */
 void ritem_print PARAMS ((FILE *out));