Added boost header

test/external/boost/wave/cpplexer/token_cache.hpp

@@ -0,0 +1,72 @@
+/*=============================================================================
+    Boost.Wave: A Standard compliant C++ preprocessor library
+
+    http://www.boost.org/
+
+    Copyright (c) 2001-2011 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)