X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/073f92889fed2bb511833920e841243a749223ca..c4bd5bf7c5b63334e8bb67af294800d4aec0fe06:/src/symtab.h

diff --git a/src/symtab.h b/src/symtab.h
index 0f852b7a..243d3d0c 100644
--- a/src/symtab.h
+++ b/src/symtab.h
@@ -20,6 +20,11 @@
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.  */
 
+/**
+ * \file symtab.h
+ * \brief Manipulating ::symbol.
+ */
+
 #ifndef SYMTAB_H_
 # define SYMTAB_H_
 
@@ -31,16 +36,16 @@
 | Symbols.  |
 `----------*/
 
-/* Symbol classes.  */
+/** Symbol classes.  */
 typedef enum
 {
-  unknown_sym,
-  token_sym,		/* terminal symbol */
-  nterm_sym		/* non-terminal */
+  unknown_sym,          /**< Undefined.  */
+  token_sym,		/**< Terminal. */
+  nterm_sym		/**< Non-terminal. */
 } symbol_class;
 
 
-/* Internal token numbers. */
+/** Internal token numbers. */
 typedef int symbol_number;
 #define SYMBOL_NUMBER_MAXIMUM INT_MAX
 
@@ -51,21 +56,40 @@ typedef struct symbol symbol;
    symbol_check_alias_consistency.  */
 struct symbol
 {
-  /* The key, name of the symbol.  */
+  /** The key, name of the symbol.  */
   uniqstr tag;
-  /* The location of its first occurrence.  */
+  /** The location of its first occurrence.  */
   location location;
 
-  /* Its %type and associated printer and destructor.  */
+  /** Its \c \%type.  */
   uniqstr type_name;
+  /** Its \c \%type's location.  */
   location type_location;
 
-  /* Does not own the memory. */
+  /** Any \c \%destructor declared specifically for this symbol.
+
+     Access this field only through <tt>symbol</tt>'s interface functions.  For
+     example, if <tt>symbol::destructor = NULL</tt>, the default
+     \c \%destructor or a per-type \c \%destructor might be appropriate, and
+     \c symbol_destructor_get will compute the correct one.  */
   const char *destructor;
+
+  /** The location of \c symbol::destructor.
+
+     Access this field only through <tt>symbol</tt>'s interface functions.
+     \sa symbol::destructor  */
   location destructor_location;
 
-  /* Does not own the memory. */
+  /** Any \c \%printer declared specifically for this symbol.
+
+     Access this field only through <tt>symbol</tt>'s interface functions.
+     \sa symbol::destructor  */
   const char *printer;
+
+  /** The location of \c symbol::printer.
+
+     Access this field only through <tt>symbol</tt>'s interface functions.
+     \sa symbol::destructor  */
   location printer_location;
 
   symbol_number number;
@@ -82,7 +106,7 @@ struct symbol
   bool declared;
 };
 
-/* Undefined user number.  */
+/** Undefined user number.  */
 #define USER_NUMBER_UNDEFINED -1
 
 /* `symbol->user_token_number == USER_NUMBER_ALIAS' means this symbol
@@ -94,69 +118,151 @@ struct symbol
 /* Undefined internal token number.  */
 #define NUMBER_UNDEFINED (-1)
 
-/* Print a symbol (for debugging). */
+/** Print a symbol (for debugging). */
 void symbol_print (symbol *s, FILE *f);
 
-/* Fetch (or create) the symbol associated to KEY.  */
+/** Fetch (or create) the symbol associated to KEY.  */
+symbol *symbol_from_uniqstr (const uniqstr key, location loc);
+
+/** Fetch (or create) the symbol associated to KEY.  */
 symbol *symbol_get (const char *key, location loc);
 
-/* Generate a dummy nonterminal, whose name cannot conflict with the
-   user's names.  */
+/** Generate a dummy nonterminal.
+
+   Its name cannot conflict with the user's names.  */
 symbol *dummy_symbol_get (location loc);
 
-/* Declare the new symbol SYM.  Make it an alias of SYMVAL.  */
+/** Is this a dummy nonterminal?  */
+bool symbol_is_dummy (const symbol *sym);
+
+/** Declare the new symbol \c sym.  Make it an alias of \c symval.  */
 void symbol_make_alias (symbol *sym, symbol *symval, location loc);
 
-/* Set the TYPE_NAME associated with SYM.  Do nothing if passed 0 as
-   TYPE_NAME.  */
+/** Set the \c type_name associated with \c sym.
+
+    Do nothing if passed 0 as \c type_name.  */
 void symbol_type_set (symbol *sym, uniqstr type_name, location loc);
 
-/* Set the DESTRUCTOR associated with SYM.  */
+/** Set the \c destructor associated with \c sym.  */
 void symbol_destructor_set (symbol *sym, const char *destructor, location loc);
 
-/* Set the PRINTER associated with SYM.  */
+/** Get the computed \c \%destructor for \c sym, or \c NULL if none.   */
+const char *symbol_destructor_get (symbol *sym);
+
+/** Get the grammar location of the computed \c \%destructor for \c sym.
+ 
+  \pre <tt>symbol_destructor_get (sym) != NULL</tt> */
+location symbol_destructor_location_get (symbol *sym);
+
+/** Set the \c printer associated with \c sym.  */
 void symbol_printer_set (symbol *sym, const char *printer, location loc);
 
-/* Set the PRECEDENCE associated with SYM.  Ensure that SYMBOL is a
-   terminal.  Do nothing if invoked with UNDEF_ASSOC as ASSOC.  */
+/** Get the computed \c \%printer for \c sym, or \c NULL if none.  */
+const char *symbol_printer_get (symbol *sym);
+
+/** Get the grammar location of the computed \c \%printer for \c sym.
+
+  \pre <tt>symbol_printer_get (sym) != NULL</tt> */
+location symbol_printer_location_get (symbol *sym);
+
+/* Set the \c precedence associated with \c sym.
+
+   Ensure that \a symbol is a terminal.
+   Do nothing if invoked with \c undef_assoc as \c assoc.  */
 void symbol_precedence_set (symbol *sym, int prec, assoc a, location loc);
 
-/* Set the CLASS associated with SYM.  */
+/** Set the \c class associated with \c sym.  */
 void symbol_class_set (symbol *sym, symbol_class class, location loc,
 		       bool declaring);
 
-/* Set the USER_TOKEN_NUMBER associated with SYM.  */
+/** Set the \c user_token_number associated with \c sym.  */
 void symbol_user_token_number_set (symbol *sym, int user_number, location loc);
 
 
-/* Distinguished symbols.  AXIOM is the real start symbol, that used
-   by the automaton.  STARTSYMBOL is the one specified by the user.
-   */
+/** The error token. */
 extern symbol *errtoken;
+/** The token for unknown tokens.  */
 extern symbol *undeftoken;
+/** The end of input token.  */
 extern symbol *endtoken;
+/** The genuine start symbol.
+
+   $accept: start-symbol $end */
 extern symbol *accept;
+
+/** The user start symbol. */
 extern symbol *startsymbol;
+/** The location of the \c \%start declaration.  */
 extern location startsymbol_location;
 
 
-/*---------------.
-| Symbol table.  |
-`---------------*/
+/*-----------------.
+| Semantic types.  |
+`-----------------*/
 
+/** A semantic type and its associated \c \%destructor and \c \%printer.
+   
+   Access the fields of this struct only through the interface functions in
+   this file.  \sa symbol::destructor  */
+typedef struct semantic_type {
+  /** The key, name of the semantic type.  */
+  uniqstr tag;
+
+  /** Any \c %destructor declared for this semantic type.  */
+  const char *destructor;
+  /** The location of \c semantic_type::destructor.  */
+  location destructor_location;
+
+  /** Any \c %printer declared for this semantic type.  */
+  const char *printer;
+  /** The location of \c semantic_type::printer.  */
+  location printer_location;
+} semantic_type;
+
+/** Fetch (or create) the semantic type associated to KEY.  */
+semantic_type *semantic_type_from_uniqstr (const uniqstr key);
+
+/** Fetch (or create) the semantic type associated to KEY.  */
+semantic_type *semantic_type_get (const char *key);
 
-/* Create the symbol table.  */
+/** Set the \c destructor associated with \c type.  */
+void semantic_type_destructor_set (semantic_type *type, const char *destructor,
+                                   location loc);
+
+/** Set the \c printer associated with \c type.  */
+void semantic_type_printer_set (semantic_type *type, const char *printer,
+                                location loc);
+
+/*----------------------------------.
+| Symbol and semantic type tables.  |
+`----------------------------------*/
+
+/** Create the symbol and semantic type tables.  */
 void symbols_new (void);
 
-/* Free all the memory allocated for symbols.  */
+/** Free all the memory allocated for symbols and semantic types.  */
 void symbols_free (void);
 
-/* Check that all the symbols are defined.  Report any undefined
-   symbols and consider them nonterminals.  */
+/** Check that all the symbols are defined.
+
+    Report any undefined symbols and consider them nonterminals.  */
 void symbols_check_defined (void);
 
-/* Perform various sanity checks, assign symbol numbers, and set up
-   TOKEN_TRANSLATIONS.  */
+/** Sanity checks and #token_translations construction.
+
+   Perform various sanity checks, assign symbol numbers, and set up
+   #token_translations.  */
 void symbols_pack (void);
 
+
+/*-----------------------------------.
+| Default %destructor and %printer.  |
+`-----------------------------------*/
+
+/** Set the default \c \%destructor.  */
+void default_destructor_set (const char *destructor, location loc);
+
+/** Set the default \c \%printer.  */
+void default_printer_set (const char *printer, location loc);
+
 #endif /* !SYMTAB_H_ */