| // 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 |