src/symlist.h

   1 /* Lists of symbols for Bison
   2
   3    Copyright (C) 2002, 2005, 2006, 2007 Free Software Foundation, Inc.
   4
   5    This file is part of Bison, the GNU Compiler Compiler.
   6
   7    Bison is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    Bison is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bison; see the file COPYING.  If not, write to
  19    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 #ifndef SYMLIST_H_
  23 # define SYMLIST_H_
  24
  25 # include "location.h"
  26 # include "scan-code.h"
  27 # include "symtab.h"
  28
  29 /* A list of symbols, used during the parsing to store the rules.  */
  30 typedef struct symbol_list
  31 {
  32   /**
  33    * Whether this node contains a symbol, a semantic type, a \c <*>, or a
  34    * \c <>.
  35    */
  36   enum {
  37     SYMLIST_SYMBOL, SYMLIST_TYPE,
  38     SYMLIST_DEFAULT_TAGGED, SYMLIST_DEFAULT_TAGLESS
  39   } content_type;
  40   union {
  41     /**
  42      * The symbol or \c NULL iff
  43      * <tt>symbol_list::content_type = SYMLIST_SYMBOL</tt>.
  44      */
  45     symbol *sym;
  46     /**
  47      * The semantic type iff <tt>symbol_list::content_type = SYMLIST_TYPE</tt>.
  48      */
  49     uniqstr type_name;
  50   } content;
  51   location location;
  52
  53   /* If this symbol is the generated lhs for a midrule but this is the rule in
  54      whose rhs it appears, MIDRULE = a pointer to that midrule.  */
  55   struct symbol_list *midrule;
  56
  57   /* If this symbol is the generated lhs for a midrule and this is that
  58      midrule, MIDRULE_PARENT_RULE = a pointer to the rule in whose rhs it
  59      appears, and MIDRULE_PARENT_RHS_INDEX = its rhs index (1-origin) in the
  60      parent rule.  */
  61   struct symbol_list *midrule_parent_rule;
  62   int midrule_parent_rhs_index;
  63
  64   /* The action is attached to the LHS of a rule. */
  65   const char *action;
  66   location action_location;
  67
  68   /* Whether this symbol's value is used in the current action.  */
  69   bool used;
  70
  71   /* Precedence/associativity.  */
  72   symbol *ruleprec;
  73   int dprec;
  74   int merger;
  75   location merger_declaration_location;
  76
  77   /* The list.  */
  78   struct symbol_list *next;
  79 } symbol_list;
  80
  81
  82 /** Create a list containing \c sym at \c loc.  */
  83 symbol_list *symbol_list_sym_new (symbol *sym, location loc);
  84
  85 /** Create a list containing \c type_name at \c loc.  */
  86 symbol_list *symbol_list_type_new (uniqstr type_name, location loc);
  87
  88 /** Create a list containing a \c <*> at \c loc.  */
  89 symbol_list *symbol_list_default_tagged_new (location loc);
  90 /** Create a list containing a \c <> at \c loc.  */
  91 symbol_list *symbol_list_default_tagless_new (location loc);
  92
  93 /** Print this list.
  94
  95   \pre For every node \c n in the list, <tt>n->content_type =
  96   SYMLIST_SYMBOL</tt>.  */
  97 void symbol_list_syms_print (const symbol_list *l, FILE *f);
  98
  99 /** Prepend \c node to \c list.  */
 100 symbol_list *symbol_list_prepend (symbol_list *list, symbol_list *node);
 101
 102 /** Free \c list, but not the items it contains.  */
 103 void symbol_list_free (symbol_list *list);
 104
 105 /** Return the length of \c l. */
 106 int symbol_list_length (symbol_list const *l);
 107
 108 /** Get item \c n in symbol list \c l.  */
 109 symbol_list *symbol_list_n_get (symbol_list *l, int n);
 110
 111 /* Get the data type (alternative in the union) of the value for
 112    symbol N in rule RULE.  */
 113 uniqstr symbol_list_n_type_name_get (symbol_list *l, location loc, int n);
 114
 115 /** Set the \c \%destructor for \c node as \c code at \c loc.  */
 116 void symbol_list_destructor_set (symbol_list *node, char const *code,
 117                                  location loc);
 118
 119 /** Set the \c \%printer for \c node as \c code at \c loc.  */
 120 void symbol_list_printer_set (symbol_list *node, char const *code,
 121                               location loc);
 122
 123 #endif /* !SYMLIST_H_ */