ceph/src/boost/boost/range/detail/safe_bool.hpp

   1 //  This header intentionally has no include guards.
   2 //
   3 //  Copyright (c) 2010 Neil Groves
   4 //  Distributed under the Boost Software License, Version 1.0.
   5 //  See accompanying file LICENSE_1_0.txt or copy at
   6 //  http://www.boost.org/LICENSE_1_0.txt
   7 //
   8 // This code utilises the experience gained during the evolution of
   9 // <boost/smart_ptr/operator_bool.hpp>
  10 #ifndef BOOST_RANGE_SAFE_BOOL_INCLUDED_HPP
  11 #define BOOST_RANGE_SAFE_BOOL_INCLUDED_HPP
  12
  13 #include <boost/config.hpp>
  14 #include <boost/range/config.hpp>
  15
  16 namespace boost
  17 {
  18     namespace range_detail
  19     {
  20
  21 template<class DataMemberPtr>
  22 class safe_bool
  23 {
  24 public:
  25     typedef safe_bool this_type;
  26
  27 #if (defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, < 0x570)) || defined(__CINT_)
  28     typedef bool unspecified_bool_type;
  29     static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr)
  30     {
  31         return x;
  32     }
  33 #elif defined(_MANAGED)
  34     static void unspecified_bool(this_type***)
  35     {
  36     }
  37     typedef void(*unspecified_bool_type)(this_type***);
  38     static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr)
  39     {
  40         return x ? unspecified_bool : 0;
  41     }
  42 #elif \
  43     ( defined(__MWERKS__) && BOOST_WORKAROUND(__MWERKS__, < 0x3200) ) || \
  44     ( defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 304) ) || \
  45     ( defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, <= 0x590) )
  46
  47     typedef bool (this_type::*unspecified_bool_type)() const;
  48
  49     static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr)
  50     {
  51         return x ? &this_type::detail_safe_bool_member_fn : 0;
  52     }
  53 private:
  54     bool detail_safe_bool_member_fn() const { return false; }
  55 #else
  56     typedef DataMemberPtr unspecified_bool_type;
  57     static unspecified_bool_type to_unspecified_bool(const bool x, DataMemberPtr p)
  58     {
  59         return x ? p : 0;
  60     }
  61 #endif
  62 private:
  63     safe_bool();
  64     safe_bool(const safe_bool&);
  65     void operator=(const safe_bool&);
  66     ~safe_bool();
  67 };
  68
  69     } // namespace range_detail
  70 } // namespace boost
  71
  72 #endif // include guard