location.hh

GNU的词法/语法分析器bison源码

/* A Bison parser, made by GNU Bison 2.1.  */

/* Location class for Bison C++ parsers,
   Copyright (C) 2002, 2003, 2004, 2005 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 2, 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, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.  */

/**
 ** \file location.hh
 ** Define the location class.
 */

#ifndef BISON_LOCATION_HH
# define BISON_LOCATION_HH

# include <iostream>
# include <string>
# include "position.hh"

namespace yy
{

  /// Abstract a location.
  class location
  {
    /** \name Ctor & dtor.
     ** \{ */
  public:
    /// Construct a location.
    location () :
      begin (),
      end ()
    {
    }
    /** \} */


    /** \name Line and Column related manipulators
     ** \{ */
  public:
    /// Reset initial location to final location.
    inline void step ()
    {
      begin = end;
    }

    /// Extend the current location to the COUNT next columns.
    inline void columns (unsigned int count = 1)
    {
      end += count;
    }

    /// Extend the current location to the COUNT next lines.
    inline void lines (unsigned int count = 1)
    {
      end.lines (count);
    }
    /** \} */


  public:
    /// Beginning of the located region.
    position begin;
    /// End of the located region.
    position end;
  };

  /// Join two location objects to create a location.
  inline const location operator+ (const location& begin, const location& end)
  {
    location res = begin;
    res.end = end.end;
    return res;
  }

  /// Add two location objects.
  inline const location operator+ (const location& begin, unsigned int width)
  {
    location res = begin;
    res.columns (width);
    return res;
  }

  /// Add and assign a location.
  inline location& operator+= (location& res, unsigned int width)
  {
    res.columns (width);
    return res;
  }

  /** \brief Intercept output stream redirection.
   ** \param ostr the destination output stream
   ** \param loc a reference to the location to redirect
   **
   ** Avoid duplicate information.
   */
  inline std::ostream& operator<< (std::ostream& ostr, const location& loc)
  {
    position last = loc.end - 1;
    ostr << loc.begin;
    if (last.filename
	&& (!loc.begin.filename
	    || *loc.begin.filename != *last.filename))
      ostr << '-' << last;
    else if (loc.begin.line != last.line)
      ostr << '-' << last.line  << '.' << last.column;
    else if (loc.begin.column != last.column)
      ostr << '-' << last.column;
    return ostr;
  }

}

#endif // not BISON_LOCATION_HH