Comment changes.

[bison.git] / data / lalr1.cc

diff --git a/data/lalr1.cc b/data/lalr1.cc
index 6c9927d64db6ec3662d5446b9bee31054c942f9a..86e6fd086db3d0eb146a87bdaf8c1d4dbfb6f479 100644 (file)
--- a/data/lalr1.cc
+++ b/data/lalr1.cc
@@ -42,27 +42,10 @@ m4_define([b4_integral_parser_table_define],
 
 # b4_symbol_value_template(VAL, [TYPE])
 # -------------------------------------
 
 # b4_symbol_value_template(VAL, [TYPE])
 # -------------------------------------

-# Same as b4_symbol_value, but used in a template method.
+# Same as b4_symbol_value, but used in a template method.  It makes
+# a difference when using variants.

 m4_copy([b4_symbol_value], [b4_symbol_value_template])
 
 m4_copy([b4_symbol_value], [b4_symbol_value_template])
 

-# How the semantic value is extracted when using variants.
-b4_variant_if([
-  # b4_symbol_value(VAL, [TYPE])
-  # ----------------------------
-  m4_define([b4_symbol_value],
-  [m4_ifval([$2],
-            [$1.as< $2 >()],
-            [$1])])
-
-  # b4_symbol_value_template(VAL, [TYPE])
-  # -------------------------------------
-  # Same as b4_symbol_value, but used in a template method.
-  m4_define([b4_symbol_value_template],
-  [m4_ifval([$2],
-            [$1.template as< $2 >()],
-            [$1])])
-]) # b4_variant_if
-

 
 # b4_lex_symbol_if([IF-YYLEX-RETURNS-A-COMPLETE-SYMBOL], [IF-NOT])
 # ----------------------------------------------------------------
 
 # b4_lex_symbol_if([IF-YYLEX-RETURNS-A-COMPLETE-SYMBOL], [IF-NOT])
 # ----------------------------------------------------------------


@@ -80,14 +63,14 @@ m4_define([b4_assert_if],
 # --------------------
 # Expansion of $<TYPE>$.
 m4_define([b4_lhs_value],
 # --------------------
 # Expansion of $<TYPE>$.
 m4_define([b4_lhs_value],

-[b4_symbol_value([yylhs.value], [$1])])
+          [b4_symbol_value([yylhs.value], [$1])])

 
 
 # b4_lhs_location()
 # -----------------
 # Expansion of @$.
 m4_define([b4_lhs_location],
 
 
 # b4_lhs_location()
 # -----------------
 # Expansion of @$.
 m4_define([b4_lhs_location],

-[yylhs.location])
+          [yylhs.location])

 
 
 # b4_rhs_data(RULE-LENGTH, NUM)
 
 
 # b4_rhs_data(RULE-LENGTH, NUM)


@@ -99,7 +82,7 @@ m4_define([b4_rhs_data],
 
 
 # b4_rhs_state(RULE-LENGTH, NUM)
 
 
 # b4_rhs_state(RULE-LENGTH, NUM)

-# -----------------------------
+# ------------------------------

 # The state corresponding to the symbol #NUM, where the current
 # rule has RULE-LENGTH symbols on RHS.
 m4_define([b4_rhs_state],
 # The state corresponding to the symbol #NUM, where the current
 # rule has RULE-LENGTH symbols on RHS.
 m4_define([b4_rhs_state],


@@ -121,6 +104,7 @@ m4_define([b4_rhs_value],
 m4_define([b4_rhs_location],
           [b4_rhs_data([$1], [$2]).location])
 
 m4_define([b4_rhs_location],
           [b4_rhs_data([$1], [$2]).location])
 

+

 # b4_symbol_action(SYMBOL-NUM, KIND)
 # ----------------------------------
 # Run the action KIND (destructor or printer) for SYMBOL-NUM.
 # b4_symbol_action(SYMBOL-NUM, KIND)
 # ----------------------------------
 # Run the action KIND (destructor or printer) for SYMBOL-NUM.


@@ -132,7 +116,7 @@ m4_define([b4_symbol_action],
                               b4_symbol_if([$1], [has_type],
                                            [b4_symbol([$1], [type])]))])dnl
 m4_pushdef([b4_at_dollar], [yysym.location])dnl
                               b4_symbol_if([$1], [has_type],
                                            [b4_symbol([$1], [type])]))])dnl
 m4_pushdef([b4_at_dollar], [yysym.location])dnl

-      case $1: // b4_symbol([$1], [tag])
+      b4_symbol_case_([$1])

 b4_syncline([b4_symbol([$1], [$2_line])], ["b4_symbol([$1], [$2_file])"])
         b4_symbol([$1], [$2])
 b4_syncline([@oline@], [@ofile@])
 b4_syncline([b4_symbol([$1], [$2_line])], ["b4_symbol([$1], [$2_file])"])
         b4_symbol([$1], [$2])
 b4_syncline([@oline@], [@ofile@])


@@ -287,60 +271,6 @@ m4_define([b4_symbol_constructor_definitions],
 b4_symbol_foreach([b4_symbol_constructor_definition_])])])
 
 
 b4_symbol_foreach([b4_symbol_constructor_definition_])])])
 
 

-# b4_symbol_variant(YYTYPE, YYVAL, ACTION, [ARGS])
-# ------------------------------------------------
-# Run some ACTION ("build", or "destroy") on YYVAL of symbol type
-# YYTYPE.
-m4_define([b4_symbol_variant],
-[m4_pushdef([b4_dollar_dollar],
-            [$2.$3< $][3 >(m4_shift3($@))])dnl
-  switch ($1)
-    {
-b4_type_foreach([b4_type_action_])[]dnl
-      default:
-        break;
-    }
-m4_popdef([b4_dollar_dollar])dnl
-])
-
-
-# _b4_char_sizeof_counter
-# -----------------------
-# A counter used by _b4_char_sizeof_dummy to create fresh symbols.
-m4_define([_b4_char_sizeof_counter],
-[0])
-
-# _b4_char_sizeof_dummy
-# ---------------------
-# At each call return a new C++ identifier.
-m4_define([_b4_char_sizeof_dummy],
-[m4_define([_b4_char_sizeof_counter], m4_incr(_b4_char_sizeof_counter))dnl
-dummy[]_b4_char_sizeof_counter])
-
-
-# b4_char_sizeof_(SYMBOL-NUM)
-# ---------------------------
-# A comment describing this symbol.
-m4_define([b4_char_sizeof_],
-[      // b4_symbol([$1], [tag])
-])
-
-# b4_char_sizeof(SYMBOL-NUMS)
-# --------------------------
-# To be mapped on the list of type names to produce:
-#
-#    char dummy1[sizeof(type_name_1)];
-#    char dummy2[sizeof(type_name_2)];
-#
-# for defined type names.
-m4_define([b4_char_sizeof],
-[b4_symbol_if([$1], [has_type],
-[
-m4_map([b4_char_sizeof_], [$@])dnl
-      char _b4_char_sizeof_dummy@{sizeof([b4_symbol([$1], [type])])@};
-])])
-
-

 # b4_yytranslate_definition
 # -------------------------
 # Define yytranslate_.  Sometimes we want it in the header file,
 # b4_yytranslate_definition
 # -------------------------
 # Define yytranslate_.  Sometimes we want it in the header file,


@@ -384,6 +314,8 @@ b4_locations_if(
 [# Backward compatibility.
 m4_define([b4_location_constructors])
 m4_include(b4_pkgdatadir/[location.cc])])
 [# Backward compatibility.
 m4_define([b4_location_constructors])
 m4_include(b4_pkgdatadir/[location.cc])])

+m4_include(b4_pkgdatadir/[stack.hh])
+b4_variant_if([m4_include(b4_pkgdatadir/[variant.hh])])

 
 # We do want M4 expansion after # for CPP macros.
 m4_changecom()
 
 # We do want M4 expansion after # for CPP macros.
 m4_changecom()


@@ -407,104 +339,7 @@ dnl FIXME: This is wrong, we want computed header guards.
 ]b4_namespace_open[
 ]b4_locations_if([  class position;
   class location;])[
 ]b4_namespace_open[
 ]b4_locations_if([  class position;
   class location;])[

-]b4_variant_if(
-[[
-  /// A char[S] buffer to store and retrieve objects.
-  ///
-  /// Sort of a variant, but does not keep track of the nature
-  /// of the stored data, since that knowledge is available
-  /// via the current state.
-  template <size_t S>
-  struct variant
-  {]b4_assert_if([
-    /// Whether something is contained.
-    bool built;
-])[
-    /// Empty construction.
-    inline
-    variant ()]b4_assert_if([
-      : built(false)])[
-    {}
-
-    /// Instantiate a \a T in here.
-    template <typename T>
-    inline T&
-    build()
-    {]b4_assert_if([
-      assert(!built);
-      built = true;])[
-      return *new (buffer) T;
-    }
-
-    /// Instantiate a \a T in here from \a t.
-    template <typename T>
-    inline T&
-    build(const T& t)
-    {]b4_assert_if([
-      assert(!built);
-      built = true;])[
-      return *new (buffer) T(t);
-    }
-
-    /// Construct and fill.
-    template <typename T>
-    inline
-    variant (const T& t)]b4_assert_if([
-      : built(true)])[
-    {
-      new (buffer) T(t);
-    }
-
-    /// Accessor to a built \a T.
-    template <typename T>
-    inline T&
-    as()
-    {]b4_assert_if([
-      assert(built);])[
-      return reinterpret_cast<T&>(buffer);
-    }
-
-    /// Const accessor to a built \a T (for %printer).
-    template <typename T>
-    inline const T&
-    as() const
-    {]b4_assert_if([
-      assert(built);])[
-      return reinterpret_cast<const T&>(buffer);
-    }
-
-    /// Swap the content with \a other.
-    template <typename T>
-    inline void
-    swap(variant<S>& other)
-    {
-      std::swap(as<T>(), other.as<T>());
-    }
-
-    /// Assign the content of \a other to this.
-    /// Destroys \a other.
-    template <typename T>
-    inline void
-    build(variant<S>& other)
-    {
-      build<T>();
-      swap<T>(other);
-      other.destroy<T>();
-    }
-
-    /// Destroy the stored \a T.
-    template <typename T>
-    inline void
-    destroy()
-    {
-      as<T>().~T();]b4_assert_if([
-      built = false;])[
-    }
-
-    /// A buffer large enough to store any of the semantic values.
-    char buffer[S];
-  };
-]])[
+]b4_variant_if([b4_variant_definition])[

 ]b4_namespace_close[
 
 ]b4_locations_if([#include "location.hh"])[
 ]b4_namespace_close[
 
 ]b4_locations_if([#include "location.hh"])[


@@ -1196,7 +1031,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
     /* Variants are always initialized to an empty instance of the
        correct type. The default $$=$1 rule is NOT applied when using
        variants */
     /* Variants are always initialized to an empty instance of the
        correct type. The default $$=$1 rule is NOT applied when using
        variants */

-    ]b4_symbol_variant([[yyr1_@{yyn@}]], [yylhs.value], [build])[],[
+    ]b4_symbol_variant([[yyr1_@{yyn@}]], [yylhs.value], [build]),[

     /* If YYLEN is nonzero, implement the default value of the action:
        `$$ = $1'.  Otherwise, use the top of the stack.
 
     /* If YYLEN is nonzero, implement the default value of the action:
        `$$ = $1'.  Otherwise, use the top of the stack.
 


@@ -1234,16 +1069,18 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
     yylhs.state = yystate;
     YY_SYMBOL_PRINT ("-> $$ =", yylhs);
 ]b4_variant_if([[
     yylhs.state = yystate;
     YY_SYMBOL_PRINT ("-> $$ =", yylhs);
 ]b4_variant_if([[

-    // Destroy the lhs symbols.
+    // Destroy the rhs symbols.

     for (int i = 0; i < yylen; ++i)
     for (int i = 0; i < yylen; ++i)

-      // Destroy a variant which value may have be swapped with
-      // yylhs.value.  The value of yylhs.value (hence maybe one of
-      // these lhs symbols) depends on what does the default
-      // contruction for this type.  In the case of pointers for
-      // instance, nothing is done, so the value is junk.  Therefore
-      // do not try to report the content in the debug trace, it's
-      // junk.  Hence yymsg = 0.  Besides, that keeps exactly the same
-      // traces as with the other Bison skeletons.
+      // Destroy a variant which value may have been swapped with
+      // yylhs.value (for instance if the action was "std::swap($$,
+      // $1)").  The value of yylhs.value (hence possibly one of these
+      // rhs symbols) depends on the default contruction for this
+      // type.  In the case of pointers for instance, no
+      // initialization is done, so the value is junk.  Therefore do
+      // not try to report the value of symbols about to be destroyed
+      // in the debug trace, it's possibly junk.  Hence yymsg = 0.
+      // Besides, that keeps exactly the same traces as with the other
+      // Bison skeletons.

       yy_destroy_ (0, yystack_[i]);]])[
 
     yypop_ (yylen);
       yy_destroy_ (0, yystack_[i]);]])[
 
     yypop_ (yylen);


@@ -1254,9 +1091,9 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
     yypush_ (0, yylhs);
     goto yynewstate;
 
     yypush_ (0, yylhs);
     goto yynewstate;
 

-  /*------------------------------------.
-  | yyerrlab -- here on detecting error |
-  `------------------------------------*/
+  /*--------------------------------------.
+  | yyerrlab -- here on detecting error.  |
+  `--------------------------------------*/

   yyerrlab:
     /* If not already recovering from an error, report this error.  */
     if (!yyerrstatus_)
   yyerrlab:
     /* If not already recovering from an error, report this error.  */
     if (!yyerrstatus_)


@@ -1393,7 +1230,8 @@ b4_error_verbose_if([int yystate, int yytoken],
        int yychecklim = yylast_ - yyn + 1;
        int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
 
        int yychecklim = yylast_ - yyn + 1;
        int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
 

-        // Number of "expected" tokens.
+        // Number of reported tokens (one for the "unexpected", one per
+        // "expected").

        size_t yycount = 0;
         // Its maximum.
         enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };
        size_t yycount = 0;
         // Its maximum.
         enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };


@@ -1494,105 +1332,6 @@ b4_error_verbose_if([int yystate, int yytoken],
 
 ]b4_lex_symbol_if([], [b4_yytranslate_definition])[
 ]b4_namespace_close[
 
 ]b4_lex_symbol_if([], [b4_yytranslate_definition])[
 ]b4_namespace_close[

-

 ]b4_epilogue[]dnl
 ]b4_epilogue[]dnl

-@output(b4_dir_prefix[]stack.hh@)@
-b4_copyright([Stack handling for Bison parsers in C++])[
-
-#ifndef BISON_STACK_HH
-# define BISON_STACK_HH
-
-#include <deque>
-
-]b4_namespace_open[
-  template <class T, class S = std::deque<T> >
-  class stack
-  {
-  public:
-
-    // Hide our reversed order.
-    typedef typename S::reverse_iterator iterator;
-    typedef typename S::const_reverse_iterator const_iterator;
-
-    stack () : seq_ ()
-    {
-    }
-
-    stack (unsigned int n) : seq_ (n)
-    {
-    }
-
-    inline
-    T&
-    operator [] (unsigned int i)
-    {
-      return seq_[i];
-    }
-
-    inline
-    const T&
-    operator [] (unsigned int i) const
-    {
-      return seq_[i];
-    }
-
-    inline
-    void
-    push (const T& t)
-    {
-      seq_.push_front (t);
-    }
-
-    inline
-    void
-    pop (unsigned int n = 1)
-    {
-      for (; n; --n)
-       seq_.pop_front ();
-    }
-
-    inline
-    typename S::size_type
-    size () const
-    {
-      return seq_.size ();
-    }
-
-    inline const_iterator begin () const { return seq_.rbegin (); }
-    inline const_iterator end ()   const { return seq_.rend ();   }
-
-  private:
-    /// The wrapped container.
-    S seq_;
-  };
-
-  /// Present a slice of the top of a stack.
-  template <class T, class S = stack<T> >
-  class slice
-  {
-  public:
-
-    slice (const S& stack,
-          unsigned int range) : stack_ (stack),
-                                range_ (range)
-    {
-    }
-
-    inline
-    const T&
-    operator [] (unsigned int i) const
-    {
-      return stack_[range_ - i];
-    }
-
-  private:
-
-    const S& stack_;
-    unsigned int range_;
-  };
-]b4_namespace_close[
-
-#endif // not BISON_STACK_HH[]dnl
-]

 m4_divert_pop(0)
 m4_popdef([b4_copyright_years])dnl
 m4_divert_pop(0)
 m4_popdef([b4_copyright_years])dnl