/*=============================================================================

    Boost.Wave: A Standard compliant C++ preprocessor library



    http://www.boost.org/



    Copyright (c) 2001-2008 Hartmut Kaiser. Distributed under the Boost

    Software License, Version 1.0. (See accompanying file

    LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

=============================================================================*/



#if !defined(TOKEN_CACHE_HPP_4D2320B7_1D56_4113_A114_397E70FA438C_INCLUDED)

#define TOKEN_CACHE_HPP_4D2320B7_1D56_4113_A114_397E70FA438C_INCLUDED



#include <vector>



#include <boost/wave/wave_config.hpp>

#include <boost/wave/token_ids.hpp>



// this must occur after all of the includes and before any code appears

#ifdef BOOST_HAS_ABI_HEADERS

#include BOOST_ABI_PREFIX

#endif



///////////////////////////////////////////////////////////////////////////////

namespace boost {

namespace wave {

namespace cpplexer {



///////////////////////////////////////////////////////////////////////////////

//

//  The token_cache template is used to cache the tokens corresponding to the

//  keywords, operators and other constant language elements.

//

//  This avoids repeated construction of these tokens, which is especially

//  effective when used in conjunction with a copy on write string 

//  implementation (COW string).

//

///////////////////////////////////////////////////////////////////////////////

template <typename StringT>

class token_cache 

{

public:

    token_cache()

    :   cache(T_LAST_TOKEN - T_FIRST_TOKEN)

    {

        typename std::vector<StringT>::iterator it = cache.begin();

        for (unsigned int i = T_FIRST_TOKEN; i < T_LAST_TOKEN;  ++i, ++it)

        {

            *it = StringT(boost::wave::get_token_value(token_id(i)));

        }

    }



    StringT const &get_token_value(token_id id) const

    {

        return cache[BASEID_FROM_TOKEN(id) - T_FIRST_TOKEN];

    }

    

private:

    std::vector<StringT> cache;

};



///////////////////////////////////////////////////////////////////////////////

}   // namespace cpplexer 

}   // namespace wave

}   // namespace boost



// the suffix header occurs after all of the code

#ifdef BOOST_HAS_ABI_HEADERS

#include BOOST_ABI_SUFFIX

#endif



#endif // !defined(TOKEN_CACHE_HPP_4D2320B7_1D56_4113_A114_397E70FA438C_INCLUDED)

