ceph/src/boost/boost/wave/cpplexer/token_cache.hpp

   1 /*=============================================================================
   2     Boost.Wave: A Standard compliant C++ preprocessor library
   3
   4     http://www.boost.org/
   5
   6     Copyright (c) 2001-2012 Hartmut Kaiser. Distributed under the Boost
   7     Software License, Version 1.0. (See accompanying file
   8     LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 =============================================================================*/
  10
  11 #if !defined(TOKEN_CACHE_HPP_4D2320B7_1D56_4113_A114_397E70FA438C_INCLUDED)
  12 #define TOKEN_CACHE_HPP_4D2320B7_1D56_4113_A114_397E70FA438C_INCLUDED
  13
  14 #include <vector>
  15
  16 #include <boost/wave/wave_config.hpp>
  17 #include <boost/wave/token_ids.hpp>
  18
  19 // this must occur after all of the includes and before any code appears
  20 #ifdef BOOST_HAS_ABI_HEADERS
  21 #include BOOST_ABI_PREFIX
  22 #endif
  23
  24 ///////////////////////////////////////////////////////////////////////////////
  25 namespace boost {
  26 namespace wave {
  27 namespace cpplexer {
  28
  29 ///////////////////////////////////////////////////////////////////////////////
  30 //
  31 //  The token_cache template is used to cache the tokens corresponding to the
  32 //  keywords, operators and other constant language elements.
  33 //
  34 //  This avoids repeated construction of these tokens, which is especially
  35 //  effective when used in conjunction with a copy on write string
  36 //  implementation (COW string).
  37 //
  38 ///////////////////////////////////////////////////////////////////////////////
  39 template <typename StringT>
  40 class token_cache
  41 {
  42 public:
  43     token_cache()
  44     :   cache(T_LAST_TOKEN - T_FIRST_TOKEN)
  45     {
  46         typename std::vector<StringT>::iterator it = cache.begin();
  47         for (unsigned int i = T_FIRST_TOKEN; i < T_LAST_TOKEN;  ++i, ++it)
  48         {
  49             *it = StringT(boost::wave::get_token_value(token_id(i)));
  50         }
  51     }
  52
  53     StringT const &get_token_value(token_id id) const
  54     {
  55         return cache[BASEID_FROM_TOKEN(id) - T_FIRST_TOKEN];
  56     }
  57
  58 private:
  59     std::vector<StringT> cache;
  60 };
  61
  62 ///////////////////////////////////////////////////////////////////////////////
  63 }   // namespace cpplexer
  64 }   // namespace wave
  65 }   // namespace boost
  66
  67 // the suffix header occurs after all of the code
  68 #ifdef BOOST_HAS_ABI_HEADERS
  69 #include BOOST_ABI_SUFFIX
  70 #endif
  71
  72 #endif // !defined(TOKEN_CACHE_HPP_4D2320B7_1D56_4113_A114_397E70FA438C_INCLUDED)