Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

boost/exception/error_info.hpp

//Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc.

//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)

#ifndef BOOST_EXCEPTION_EE7ECCA0433B11E1923E37064924019B
#define BOOST_EXCEPTION_EE7ECCA0433B11E1923E37064924019B
namespace boost { template <class Tag,class T> class error_info; }
#endif