123 lines
2.9 KiB
C++
123 lines
2.9 KiB
C++
#ifndef BOOST_STATECHART_RESULT_HPP_INCLUDED
|
|
#define BOOST_STATECHART_RESULT_HPP_INCLUDED
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
// Copyright 2002-2010 Andreas Huber Doenni
|
|
// Distributed under the Boost Software License, Version 1.0. (See accompany-
|
|
// ing file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
|
|
#include <boost/assert.hpp>
|
|
|
|
|
|
|
|
namespace boost
|
|
{
|
|
namespace statechart
|
|
{
|
|
namespace detail
|
|
{
|
|
|
|
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
enum reaction_result
|
|
{
|
|
no_reaction,
|
|
do_forward_event,
|
|
do_discard_event,
|
|
do_defer_event,
|
|
consumed
|
|
};
|
|
|
|
struct result_utility;
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
class safe_reaction_result
|
|
{
|
|
public:
|
|
//////////////////////////////////////////////////////////////////////////
|
|
safe_reaction_result( const safe_reaction_result & other ) :
|
|
reactionResult_( other.reactionResult_ )
|
|
{
|
|
// This assert fails when an attempt is made to make multiple copies of
|
|
// a result value. This makes little sense, given the requirement that
|
|
// an obtained result value must be returned out of the react function.
|
|
BOOST_ASSERT( reactionResult_ != consumed );
|
|
other.reactionResult_ = consumed;
|
|
}
|
|
|
|
~safe_reaction_result()
|
|
{
|
|
// This assert fails when an obtained result value is not returned out
|
|
// of the react() function. This can happen if the user accidentally
|
|
// makes more than one call to reaction functions inside react() or
|
|
// accidentally makes one or more calls to reaction functions outside
|
|
// react()
|
|
BOOST_ASSERT( reactionResult_ == consumed );
|
|
}
|
|
|
|
private:
|
|
//////////////////////////////////////////////////////////////////////////
|
|
safe_reaction_result( reaction_result reactionResult ) :
|
|
reactionResult_( reactionResult )
|
|
{
|
|
}
|
|
|
|
operator reaction_result() const
|
|
{
|
|
const reaction_result val = reactionResult_;
|
|
reactionResult_ = consumed;
|
|
return val;
|
|
}
|
|
|
|
safe_reaction_result & operator=( const safe_reaction_result & );
|
|
|
|
mutable reaction_result reactionResult_;
|
|
|
|
friend struct result_utility;
|
|
};
|
|
|
|
|
|
|
|
} // namespace detail
|
|
|
|
|
|
|
|
#ifdef NDEBUG
|
|
typedef detail::reaction_result result;
|
|
#else
|
|
typedef detail::safe_reaction_result result;
|
|
#endif
|
|
|
|
|
|
namespace detail
|
|
{
|
|
|
|
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
struct result_utility
|
|
{
|
|
static ::boost::statechart::result make_result( reaction_result value )
|
|
{
|
|
return value;
|
|
}
|
|
|
|
static reaction_result get_result( ::boost::statechart::result value )
|
|
{
|
|
return value;
|
|
}
|
|
};
|
|
|
|
|
|
|
|
} // namespace detail
|
|
} // namespace statechart
|
|
} // namespace boost
|
|
|
|
|
|
|
|
#endif
|