// A Bison parser, made by GNU Bison 3.8.2.

// Skeleton interface for Bison LALR(1) parsers in C++

// Copyright (C) 2002-2015, 2018-2021 Free Software Foundation, Inc.

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

// As a special exception, you may create a larger work that contains
// part or all of the Bison parser skeleton and distribute that work
// under terms of your choice, so long as that work isn't itself a
// parser generator using the skeleton or a modified version thereof
// as a parser skeleton.  Alternatively, if you modify or redistribute
// the parser skeleton itself, you may (at your option) remove this
// special exception, which will cause the skeleton and the resulting
// Bison output files to be licensed under the GNU General Public
// License without this special exception.

// This special exception was added by the Free Software Foundation in
// version 2.2 of Bison.


/**
 ** \file aprepro_parser.h
 ** Define the SEAMS::parser class.
 */

// C++ LALR(1) parser skeleton written by Akim Demaille.

// DO NOT RELY ON FEATURES THAT ARE NOT DOCUMENTED in the manual,
// especially those whose name start with YY_ or yy_.  They are
// private implementation details that can be changed or removed.

#ifndef YY_SEAMS_APREPRO_PARSER_H_INCLUDED
# define YY_SEAMS_APREPRO_PARSER_H_INCLUDED


# include <cstdlib> // std::abort
# include <iostream>
# include <stdexcept>
# include <string>
# include <vector>

#if defined __cplusplus
# define YY_CPLUSPLUS __cplusplus
#else
# define YY_CPLUSPLUS 199711L
#endif

// Support move semantics when possible.
#if 201103L <= YY_CPLUSPLUS
# define YY_MOVE           std::move
# define YY_MOVE_OR_COPY   move
# define YY_MOVE_REF(Type) Type&&
# define YY_RVREF(Type)    Type&&
# define YY_COPY(Type)     Type
#else
# define YY_MOVE
# define YY_MOVE_OR_COPY   copy
# define YY_MOVE_REF(Type) Type&
# define YY_RVREF(Type)    const Type&
# define YY_COPY(Type)     const Type&
#endif

// Support noexcept when possible.
#if 201103L <= YY_CPLUSPLUS
# define YY_NOEXCEPT noexcept
# define YY_NOTHROW
#else
# define YY_NOEXCEPT
# define YY_NOTHROW throw ()
#endif

// Support constexpr when possible.
#if 201703 <= YY_CPLUSPLUS
# define YY_CONSTEXPR constexpr
#else
# define YY_CONSTEXPR
#endif



#ifndef YY_ATTRIBUTE_PURE
# if defined __GNUC__ && 2 < __GNUC__ + (96 <= __GNUC_MINOR__)
#  define YY_ATTRIBUTE_PURE __attribute__ ((__pure__))
# else
#  define YY_ATTRIBUTE_PURE
# endif
#endif

#ifndef YY_ATTRIBUTE_UNUSED
# if defined __GNUC__ && 2 < __GNUC__ + (7 <= __GNUC_MINOR__)
#  define YY_ATTRIBUTE_UNUSED __attribute__ ((__unused__))
# else
#  define YY_ATTRIBUTE_UNUSED
# endif
#endif

/* Suppress unused-variable warnings by "using" E.  */
#if ! defined lint || defined __GNUC__
# define YY_USE(E) ((void) (E))
#else
# define YY_USE(E) /* empty */
#endif

/* Suppress an incorrect diagnostic about yylval being uninitialized.  */
#if defined __GNUC__ && ! defined __ICC && 406 <= __GNUC__ * 100 + __GNUC_MINOR__
# if __GNUC__ * 100 + __GNUC_MINOR__ < 407
#  define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN                           \
    _Pragma ("GCC diagnostic push")                                     \
    _Pragma ("GCC diagnostic ignored \"-Wuninitialized\"")
# else
#  define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN                           \
    _Pragma ("GCC diagnostic push")                                     \
    _Pragma ("GCC diagnostic ignored \"-Wuninitialized\"")              \
    _Pragma ("GCC diagnostic ignored \"-Wmaybe-uninitialized\"")
# endif
# define YY_IGNORE_MAYBE_UNINITIALIZED_END      \
    _Pragma ("GCC diagnostic pop")
#else
# define YY_INITIAL_VALUE(Value) Value
#endif
#ifndef YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN
# define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN
# define YY_IGNORE_MAYBE_UNINITIALIZED_END
#endif
#ifndef YY_INITIAL_VALUE
# define YY_INITIAL_VALUE(Value) /* Nothing. */
#endif

#if defined __cplusplus && defined __GNUC__ && ! defined __ICC && 6 <= __GNUC__
# define YY_IGNORE_USELESS_CAST_BEGIN                          \
    _Pragma ("GCC diagnostic push")                            \
    _Pragma ("GCC diagnostic ignored \"-Wuseless-cast\"")
# define YY_IGNORE_USELESS_CAST_END            \
    _Pragma ("GCC diagnostic pop")
#endif
#ifndef YY_IGNORE_USELESS_CAST_BEGIN
# define YY_IGNORE_USELESS_CAST_BEGIN
# define YY_IGNORE_USELESS_CAST_END
#endif

# ifndef YY_CAST
#  ifdef __cplusplus
#   define YY_CAST(Type, Val) static_cast<Type> (Val)
#   define YY_REINTERPRET_CAST(Type, Val) reinterpret_cast<Type> (Val)
#  else
#   define YY_CAST(Type, Val) ((Type) (Val))
#   define YY_REINTERPRET_CAST(Type, Val) ((Type) (Val))
#  endif
# endif
# ifndef YY_NULLPTR
#  if defined __cplusplus
#   if 201103L <= __cplusplus
#    define YY_NULLPTR nullptr
#   else
#    define YY_NULLPTR 0
#   endif
#  else
#   define YY_NULLPTR ((void*)0)
#  endif
# endif

/* Debug traces.  */
#ifndef SEAMSDEBUG
# if defined YYDEBUG
#if YYDEBUG
#   define SEAMSDEBUG 1
#  else
#   define SEAMSDEBUG 0
#  endif
# else /* ! defined YYDEBUG */
#  define SEAMSDEBUG 1
# endif /* ! defined YYDEBUG */
#endif  /* ! defined SEAMSDEBUG */

namespace SEAMS {
#line 190 "aprepro_parser.h"




  /// A Bison parser.
  class Parser
  {
  public:
#ifdef SEAMSSTYPE
# ifdef __GNUC__
#  pragma GCC message "bison: do not #define SEAMSSTYPE in C++, use %define api.value.type"
# endif
    typedef SEAMSSTYPE value_type;
#else
    /// Symbol semantic values.
    union value_type
    {
#line 69 "/Users/gdsjaar/src/seacas/packages/seacas/libraries/aprepro_lib/aprepro.yy"

  double  val;          /* For returning numbers.               */
  struct symrec *tptr;  /* For returning symbol-table pointers  */
  char   *string;       /* For returning quoted strings         */
  struct array  *arrval;       /* For returning arrays                 */

#line 215 "aprepro_parser.h"

    };
#endif
    /// Backward compatibility (Bison 3.8).
    typedef value_type semantic_type;


    /// Syntax errors thrown from user actions.
    struct syntax_error : std::runtime_error
    {
      syntax_error (const std::string& m)
        : std::runtime_error (m)
      {}

      syntax_error (const syntax_error& s)
        : std::runtime_error (s.what ())
      {}

      ~syntax_error () YY_NOEXCEPT YY_NOTHROW;
    };

    /// Token kinds.
    struct token
    {
      enum token_kind_type
      {
        SEAMSEMPTY = -2,
    END = 0,                       // "end of file"
    SEAMSerror = 256,              // error
    SEAMSUNDEF = 257,              // "invalid token"
    NUM = 258,                     // NUM
    QSTRING = 259,                 // QSTRING
    UNDVAR = 260,                  // UNDVAR
    VAR = 261,                     // VAR
    SVAR = 262,                    // SVAR
    IMMVAR = 263,                  // IMMVAR
    IMMSVAR = 264,                 // IMMSVAR
    AVAR = 265,                    // AVAR
    FNCT = 266,                    // FNCT
    SFNCT = 267,                   // SFNCT
    AFNCT = 268,                   // AFNCT
    COMMA = 269,                   // COMMA
    LPAR = 270,                    // LPAR
    RPAR = 271,                    // RPAR
    LBRACK = 272,                  // LBRACK
    RBRACK = 273,                  // RBRACK
    LBRACE = 274,                  // LBRACE
    RBRACE = 275,                  // RBRACE
    SEMI = 276,                    // SEMI
    EQUAL = 277,                   // EQUAL
    EQ_PLUS = 278,                 // EQ_PLUS
    EQ_MINUS = 279,                // EQ_MINUS
    EQ_TIME = 280,                 // EQ_TIME
    EQ_DIV = 281,                  // EQ_DIV
    EQ_POW = 282,                  // EQ_POW
    QUEST = 283,                   // QUEST
    COLON = 284,                   // COLON
    LOR = 285,                     // LOR
    LAND = 286,                    // LAND
    LT = 287,                      // LT
    GT = 288,                      // GT
    LE = 289,                      // LE
    GE = 290,                      // GE
    EQ = 291,                      // EQ
    NE = 292,                      // NE
    PLU = 293,                     // PLU
    SUB = 294,                     // SUB
    DIV = 295,                     // DIV
    TIM = 296,                     // TIM
    MOD = 297,                     // MOD
    UNARY = 298,                   // UNARY
    NOT = 299,                     // NOT
    POW = 300,                     // POW
    INC = 301,                     // INC
    DEC = 302,                     // DEC
    CONCAT = 303                   // CONCAT
      };
      /// Backward compatibility alias (Bison 3.6).
      typedef token_kind_type yytokentype;
    };

    /// Token kind, as returned by yylex.
    typedef token::token_kind_type token_kind_type;

    /// Backward compatibility alias (Bison 3.6).
    typedef token_kind_type token_type;

    /// Symbol kinds.
    struct symbol_kind
    {
      enum symbol_kind_type
      {
        YYNTOKENS = 50, ///< Number of tokens.
        S_YYEMPTY = -2,
        S_YYEOF = 0,                             // "end of file"
        S_YYerror = 1,                           // error
        S_YYUNDEF = 2,                           // "invalid token"
        S_NUM = 3,                               // NUM
        S_QSTRING = 4,                           // QSTRING
        S_UNDVAR = 5,                            // UNDVAR
        S_VAR = 6,                               // VAR
        S_SVAR = 7,                              // SVAR
        S_IMMVAR = 8,                            // IMMVAR
        S_IMMSVAR = 9,                           // IMMSVAR
        S_AVAR = 10,                             // AVAR
        S_FNCT = 11,                             // FNCT
        S_SFNCT = 12,                            // SFNCT
        S_AFNCT = 13,                            // AFNCT
        S_COMMA = 14,                            // COMMA
        S_LPAR = 15,                             // LPAR
        S_RPAR = 16,                             // RPAR
        S_LBRACK = 17,                           // LBRACK
        S_RBRACK = 18,                           // RBRACK
        S_LBRACE = 19,                           // LBRACE
        S_RBRACE = 20,                           // RBRACE
        S_SEMI = 21,                             // SEMI
        S_EQUAL = 22,                            // EQUAL
        S_EQ_PLUS = 23,                          // EQ_PLUS
        S_EQ_MINUS = 24,                         // EQ_MINUS
        S_EQ_TIME = 25,                          // EQ_TIME
        S_EQ_DIV = 26,                           // EQ_DIV
        S_EQ_POW = 27,                           // EQ_POW
        S_QUEST = 28,                            // QUEST
        S_COLON = 29,                            // COLON
        S_LOR = 30,                              // LOR
        S_LAND = 31,                             // LAND
        S_LT = 32,                               // LT
        S_GT = 33,                               // GT
        S_LE = 34,                               // LE
        S_GE = 35,                               // GE
        S_EQ = 36,                               // EQ
        S_NE = 37,                               // NE
        S_PLU = 38,                              // PLU
        S_SUB = 39,                              // SUB
        S_DIV = 40,                              // DIV
        S_TIM = 41,                              // TIM
        S_MOD = 42,                              // MOD
        S_UNARY = 43,                            // UNARY
        S_NOT = 44,                              // NOT
        S_POW = 45,                              // POW
        S_INC = 46,                              // INC
        S_DEC = 47,                              // DEC
        S_CONCAT = 48,                           // CONCAT
        S_49_n_ = 49,                            // '\n'
        S_YYACCEPT = 50,                         // $accept
        S_input = 51,                            // input
        S_line = 52,                             // line
        S_bool = 53,                             // bool
        S_aexp = 54,                             // aexp
        S_sexp = 55,                             // sexp
        S_exp = 56                               // exp
      };
    };

    /// (Internal) symbol kind.
    typedef symbol_kind::symbol_kind_type symbol_kind_type;

    /// The number of tokens.
    static const symbol_kind_type YYNTOKENS = symbol_kind::YYNTOKENS;

    /// A complete symbol.
    ///
    /// Expects its Base type to provide access to the symbol kind
    /// via kind ().
    ///
    /// Provide access to semantic value.
    template <typename Base>
    struct basic_symbol : Base
    {
      /// Alias to Base.
      typedef Base super_type;

      /// Default constructor.
      basic_symbol () YY_NOEXCEPT
        : value ()
      {}

#if 201103L <= YY_CPLUSPLUS
      /// Move constructor.
      basic_symbol (basic_symbol&& that)
        : Base (std::move (that))
        , value (std::move (that.value))
      {}
#endif

      /// Copy constructor.
      basic_symbol (const basic_symbol& that);
      /// Constructor for valueless symbols.
      basic_symbol (typename Base::kind_type t);

      /// Constructor for symbols with semantic value.
      basic_symbol (typename Base::kind_type t,
                    YY_RVREF (value_type) v);

      /// Destroy the symbol.
      ~basic_symbol ()
      {
        clear ();
      }



      /// Destroy contents, and record that is empty.
      void clear () YY_NOEXCEPT
      {
        Base::clear ();
      }

      /// The user-facing name of this symbol.
      std::string name () const YY_NOEXCEPT
      {
        return Parser::symbol_name (this->kind ());
      }

      /// Backward compatibility (Bison 3.6).
      symbol_kind_type type_get () const YY_NOEXCEPT;

      /// Whether empty.
      bool empty () const YY_NOEXCEPT;

      /// Destructive move, \a s is emptied into this.
      void move (basic_symbol& s);

      /// The semantic value.
      value_type value;

    private:
#if YY_CPLUSPLUS < 201103L
      /// Assignment operator.
      basic_symbol& operator= (const basic_symbol& that);
#endif
    };

    /// Type access provider for token (enum) based symbols.
    struct by_kind
    {
      /// The symbol kind as needed by the constructor.
      typedef token_kind_type kind_type;

      /// Default constructor.
      by_kind () YY_NOEXCEPT;

#if 201103L <= YY_CPLUSPLUS
      /// Move constructor.
      by_kind (by_kind&& that) YY_NOEXCEPT;
#endif

      /// Copy constructor.
      by_kind (const by_kind& that) YY_NOEXCEPT;

      /// Constructor from (external) token numbers.
      by_kind (kind_type t) YY_NOEXCEPT;



      /// Record that this symbol is empty.
      void clear () YY_NOEXCEPT;

      /// Steal the symbol kind from \a that.
      void move (by_kind& that);

      /// The (internal) type number (corresponding to \a type).
      /// \a empty when empty.
      symbol_kind_type kind () const YY_NOEXCEPT;

      /// Backward compatibility (Bison 3.6).
      symbol_kind_type type_get () const YY_NOEXCEPT;

      /// The symbol kind.
      /// \a S_YYEMPTY when empty.
      symbol_kind_type kind_;
    };

    /// Backward compatibility for a private implementation detail (Bison 3.6).
    typedef by_kind by_type;

    /// "External" symbols: returned by the scanner.
    struct symbol_type : basic_symbol<by_kind>
    {};

    /// Build a parser object.
    Parser (class Aprepro& aprepro_yyarg);
    virtual ~Parser ();

#if 201103L <= YY_CPLUSPLUS
    /// Non copyable.
    Parser (const Parser&) = delete;
    /// Non copyable.
    Parser& operator= (const Parser&) = delete;
#endif

    /// Parse.  An alias for parse ().
    /// \returns  0 iff parsing succeeded.
    int operator() ();

    /// Parse.
    /// \returns  0 iff parsing succeeded.
    virtual int parse ();

#if SEAMSDEBUG
    /// The current debugging stream.
    std::ostream& debug_stream () const YY_ATTRIBUTE_PURE;
    /// Set the current debugging stream.
    void set_debug_stream (std::ostream &);

    /// Type for debugging levels.
    typedef int debug_level_type;
    /// The current debugging level.
    debug_level_type debug_level () const YY_ATTRIBUTE_PURE;
    /// Set the current debugging level.
    void set_debug_level (debug_level_type l);
#endif

    /// Report a syntax error.
    /// \param msg    a description of the syntax error.
    virtual void error (const std::string& msg);

    /// Report a syntax error.
    void error (const syntax_error& err);

    /// The user-facing name of the symbol whose (internal) number is
    /// YYSYMBOL.  No bounds checking.
    static std::string symbol_name (symbol_kind_type yysymbol);



    class context
    {
    public:
      context (const Parser& yyparser, const symbol_type& yyla);
      const symbol_type& lookahead () const YY_NOEXCEPT { return yyla_; }
      symbol_kind_type token () const YY_NOEXCEPT { return yyla_.kind (); }
      /// Put in YYARG at most YYARGN of the expected tokens, and return the
      /// number of tokens stored in YYARG.  If YYARG is null, return the
      /// number of expected tokens (guaranteed to be less than YYNTOKENS).
      int expected_tokens (symbol_kind_type yyarg[], int yyargn) const;

    private:
      const Parser& yyparser_;
      const symbol_type& yyla_;
    };

  private:
#if YY_CPLUSPLUS < 201103L
    /// Non copyable.
    Parser (const Parser&);
    /// Non copyable.
    Parser& operator= (const Parser&);
#endif


    /// Stored state numbers (used for stacks).
    typedef short state_type;

    /// The arguments of the error message.
    int yy_syntax_error_arguments_ (const context& yyctx,
                                    symbol_kind_type yyarg[], int yyargn) const;

    /// Generate an error message.
    /// \param yyctx     the context in which the error occurred.
    virtual std::string yysyntax_error_ (const context& yyctx) const;
    /// Compute post-reduction state.
    /// \param yystate   the current state
    /// \param yysym     the nonterminal to push on the stack
    static state_type yy_lr_goto_state_ (state_type yystate, int yysym);

    /// Whether the given \c yypact_ value indicates a defaulted state.
    /// \param yyvalue   the value to check
    static bool yy_pact_value_is_default_ (int yyvalue) YY_NOEXCEPT;

    /// Whether the given \c yytable_ value indicates a syntax error.
    /// \param yyvalue   the value to check
    static bool yy_table_value_is_error_ (int yyvalue) YY_NOEXCEPT;

    static const signed char yypact_ninf_;
    static const signed char yytable_ninf_;

    /// Convert a scanner token kind \a t to a symbol kind.
    /// In theory \a t should be a token_kind_type, but character literals
    /// are valid, yet not members of the token_kind_type enum.
    static symbol_kind_type yytranslate_ (int t) YY_NOEXCEPT;

    /// Convert the symbol name \a n to a form suitable for a diagnostic.
    static std::string yytnamerr_ (const char *yystr);

    /// For a symbol, its name in clear.
    static const char* const yytname_[];


    // Tables.
    // YYPACT[STATE-NUM] -- Index in YYTABLE of the portion describing
    // STATE-NUM.
    static const short yypact_[];

    // YYDEFACT[STATE-NUM] -- Default reduction number in state STATE-NUM.
    // Performed when YYTABLE does not specify something else to do.  Zero
    // means the default is an error.
    static const unsigned char yydefact_[];

    // YYPGOTO[NTERM-NUM].
    static const signed char yypgoto_[];

    // YYDEFGOTO[NTERM-NUM].
    static const unsigned char yydefgoto_[];

    // YYTABLE[YYPACT[STATE-NUM]] -- What to do in state STATE-NUM.  If
    // positive, shift that token.  If negative, reduce the rule whose
    // number is the opposite.  If YYTABLE_NINF, syntax error.
    static const short yytable_[];

    static const short yycheck_[];

    // YYSTOS[STATE-NUM] -- The symbol kind of the accessing symbol of
    // state STATE-NUM.
    static const signed char yystos_[];

    // YYR1[RULE-NUM] -- Symbol kind of the left-hand side of rule RULE-NUM.
    static const signed char yyr1_[];

    // YYR2[RULE-NUM] -- Number of symbols on the right-hand side of rule RULE-NUM.
    static const signed char yyr2_[];


#if SEAMSDEBUG
    // YYRLINE[YYN] -- Source line where rule number YYN was defined.
    static const short yyrline_[];
    /// Report on the debug stream that the rule \a r is going to be reduced.
    virtual void yy_reduce_print_ (int r) const;
    /// Print the state stack on the debug stream.
    virtual void yy_stack_print_ () const;

    /// Debugging level.
    int yydebug_;
    /// Debug stream.
    std::ostream* yycdebug_;

    /// \brief Display a symbol kind, value and location.
    /// \param yyo    The output stream.
    /// \param yysym  The symbol.
    template <typename Base>
    void yy_print_ (std::ostream& yyo, const basic_symbol<Base>& yysym) const;
#endif

    /// \brief Reclaim the memory associated to a symbol.
    /// \param yymsg     Why this token is reclaimed.
    ///                  If null, print nothing.
    /// \param yysym     The symbol.
    template <typename Base>
    void yy_destroy_ (const char* yymsg, basic_symbol<Base>& yysym) const;

  private:
    /// Type access provider for state based symbols.
    struct by_state
    {
      /// Default constructor.
      by_state () YY_NOEXCEPT;

      /// The symbol kind as needed by the constructor.
      typedef state_type kind_type;

      /// Constructor.
      by_state (kind_type s) YY_NOEXCEPT;

      /// Copy constructor.
      by_state (const by_state& that) YY_NOEXCEPT;

      /// Record that this symbol is empty.
      void clear () YY_NOEXCEPT;

      /// Steal the symbol kind from \a that.
      void move (by_state& that);

      /// The symbol kind (corresponding to \a state).
      /// \a symbol_kind::S_YYEMPTY when empty.
      symbol_kind_type kind () const YY_NOEXCEPT;

      /// The state number used to denote an empty symbol.
      /// We use the initial state, as it does not have a value.
      enum { empty_state = 0 };

      /// The state.
      /// \a empty when empty.
      state_type state;
    };

    /// "Internal" symbol: element of the stack.
    struct stack_symbol_type : basic_symbol<by_state>
    {
      /// Superclass.
      typedef basic_symbol<by_state> super_type;
      /// Construct an empty symbol.
      stack_symbol_type ();
      /// Move or copy construction.
      stack_symbol_type (YY_RVREF (stack_symbol_type) that);
      /// Steal the contents from \a sym to build this.
      stack_symbol_type (state_type s, YY_MOVE_REF (symbol_type) sym);
#if YY_CPLUSPLUS < 201103L
      /// Assignment, needed by push_back by some old implementations.
      /// Moves the contents of that.
      stack_symbol_type& operator= (stack_symbol_type& that);

      /// Assignment, needed by push_back by other implementations.
      /// Needed by some other old implementations.
      stack_symbol_type& operator= (const stack_symbol_type& that);
#endif
    };

    /// A stack with random access from its top.
    template <typename T, typename S = std::vector<T> >
    class stack
    {
    public:
      // Hide our reversed order.
      typedef typename S::iterator iterator;
      typedef typename S::const_iterator const_iterator;
      typedef typename S::size_type size_type;
      typedef typename std::ptrdiff_t index_type;

      stack (size_type n = 200) YY_NOEXCEPT
        : seq_ (n)
      {}

#if 201103L <= YY_CPLUSPLUS
      /// Non copyable.
      stack (const stack&) = delete;
      /// Non copyable.
      stack& operator= (const stack&) = delete;
#endif

      /// Random access.
      ///
      /// Index 0 returns the topmost element.
      const T&
      operator[] (index_type i) const
      {
        return seq_[size_type (size () - 1 - i)];
      }

      /// Random access.
      ///
      /// Index 0 returns the topmost element.
      T&
      operator[] (index_type i)
      {
        return seq_[size_type (size () - 1 - i)];
      }

      /// Steal the contents of \a t.
      ///
      /// Close to move-semantics.
      void
      push (YY_MOVE_REF (T) t)
      {
        seq_.push_back (T ());
        operator[] (0).move (t);
      }

      /// Pop elements from the stack.
      void
      pop (std::ptrdiff_t n = 1) YY_NOEXCEPT
      {
        for (; 0 < n; --n)
          seq_.pop_back ();
      }

      /// Pop all elements from the stack.
      void
      clear () YY_NOEXCEPT
      {
        seq_.clear ();
      }

      /// Number of elements on the stack.
      index_type
      size () const YY_NOEXCEPT
      {
        return index_type (seq_.size ());
      }

      /// Iterator on top of the stack (going downwards).
      const_iterator
      begin () const YY_NOEXCEPT
      {
        return seq_.begin ();
      }

      /// Bottom of the stack.
      const_iterator
      end () const YY_NOEXCEPT
      {
        return seq_.end ();
      }

      /// Present a slice of the top of a stack.
      class slice
      {
      public:
        slice (const stack& stack, index_type range) YY_NOEXCEPT
          : stack_ (stack)
          , range_ (range)
        {}

        const T&
        operator[] (index_type i) const
        {
          return stack_[range_ - i];
        }

      private:
        const stack& stack_;
        index_type range_;
      };

    private:
#if YY_CPLUSPLUS < 201103L
      /// Non copyable.
      stack (const stack&);
      /// Non copyable.
      stack& operator= (const stack&);
#endif
      /// The wrapped container.
      S seq_;
    };


    /// Stack type.
    typedef stack<stack_symbol_type> stack_type;

    /// The stack.
    stack_type yystack_;

    /// Push a new state on the stack.
    /// \param m    a debug message to display
    ///             if null, no trace is output.
    /// \param sym  the symbol
    /// \warning the contents of \a s.value is stolen.
    void yypush_ (const char* m, YY_MOVE_REF (stack_symbol_type) sym);

    /// Push a new look ahead token on the state on the stack.
    /// \param m    a debug message to display
    ///             if null, no trace is output.
    /// \param s    the state
    /// \param sym  the symbol (for its value and location).
    /// \warning the contents of \a sym.value is stolen.
    void yypush_ (const char* m, state_type s, YY_MOVE_REF (symbol_type) sym);

    /// Pop \a n symbols from the stack.
    void yypop_ (int n = 1) YY_NOEXCEPT;

    /// Constants.
    enum
    {
      yylast_ = 1324,     ///< Last index in yytable_.
      yynnts_ = 7,  ///< Number of nonterminal symbols.
      yyfinal_ = 2 ///< Termination state number.
    };


    // User arguments.
    class Aprepro& aprepro;

  };


} // SEAMS
#line 881 "aprepro_parser.h"




#endif // !YY_SEAMS_APREPRO_PARSER_H_INCLUDED