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// This header intentionally has no include guards.
//
// Copyright (c) 2010 Neil Groves
// 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
//
// This code utilises the experience gained during the evolution of
// <boost/smart_ptr/operator_bool.hpp>
#ifndef BOOST_RANGE_SAFE_BOOL_INCLUDED_HPP
#define BOOST_RANGE_SAFE_BOOL_INCLUDED_HPP
#include <boost/config.hpp>
#include <boost/range/config.hpp>
namespace boost
{
namespace range_detail
{
template<class DataMemberPtr>
class safe_bool
{
public:
typedef safe_bool this_type;
#if (defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, < 0x570)) || defined(__CINT_)
typedef bool unspecified_bool_type;
static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr)
{
return x;
}
#elif defined(_MANAGED)
static void unspecified_bool(this_type***)
{
}
typedef void(*unspecified_bool_type)(this_type***);
static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr)
{
return x ? unspecified_bool : 0;
}
#elif \
( defined(__MWERKS__) && BOOST_WORKAROUND(__MWERKS__, < 0x3200) ) || \
( defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 304) ) || \
( defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, <= 0x590) )
typedef bool (this_type::*unspecified_bool_type)() const;
static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr)
{
return x ? &this_type::detail_safe_bool_member_fn : 0;
}
private:
bool detail_safe_bool_member_fn() const { return false; }
#else
typedef DataMemberPtr unspecified_bool_type;
static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr p)
{
return x ? p : 0;
}
#endif
private:
safe_bool();
safe_bool(const safe_bool&);
void operator=(const safe_bool&);
~safe_bool();
};
} // namespace range_detail
} // namespace boost
#endif // include guard