ceph/src/boost/boost/outcome/experimental/status-code/iostream_support.hpp

   1 /* Proposed SG14 status_code
   2 (C) 2018-2019 Niall Douglas <http://www.nedproductions.biz/> (5 commits)
   3 File Created: Feb 2018
   4
   5
   6 Boost Software License - Version 1.0 - August 17th, 2003
   7
   8 Permission is hereby granted, free of charge, to any person or organization
   9 obtaining a copy of the software and accompanying documentation covered by
  10 this license (the "Software") to use, reproduce, display, distribute,
  11 execute, and transmit the Software, and to prepare derivative works of the
  12 Software, and to permit third-parties to whom the Software is furnished to
  13 do so, all subject to the following:
  14
  15 The copyright notices in the Software and this entire statement, including
  16 the above license grant, this restriction and the following disclaimer,
  17 must be included in all copies of the Software, in whole or in part, and
  18 all derivative works of the Software, unless such copies or derivative
  19 works are solely in the form of machine-executable object code generated by
  20 a source language processor.
  21
  22 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  23 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24 FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
  25 SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
  26 FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
  27 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  28 DEALINGS IN THE SOFTWARE.
  29 */
  30
  31 #ifndef BOOST_OUTCOME_SYSTEM_ERROR2_IOSTREAM_SUPPORT_HPP
  32 #define BOOST_OUTCOME_SYSTEM_ERROR2_IOSTREAM_SUPPORT_HPP
  33
  34 #include "error.hpp"
  35
  36 #include <iostream>
  37
  38 BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_BEGIN
  39
  40 /*! Print the status code to a `std::ostream &`.
  41 Requires that `DomainType::value_type` implements an `operator<<` overload for `std::ostream`.
  42 */
  43 template <class DomainType,  //
  44           typename std::enable_if<std::is_same<std::ostream, typename std::decay<decltype(std::declval<std::ostream>() << std::declval<typename status_code<DomainType>::value_type>())>::type>::value, bool>::type = true>
  45 inline std::ostream &operator<<(std::ostream &s, const status_code<DomainType> &v)
  46 {
  47   if(v.empty())
  48   {
  49     return s << "(empty)";
  50   }
  51   return s << v.domain().name().c_str() << ": " << v.value();
  52 }
  53
  54 /*! Print the erased status code to a `std::ostream &`.
  55 */
  56 template <class ErasedType> inline std::ostream &operator<<(std::ostream &s, const status_code<erased<ErasedType>> &v)
  57 {
  58   if(v.empty())
  59   {
  60     return s << "(empty)";
  61   }
  62   return s << v.domain().name().c_str() << ": " << v.message().c_str();
  63 }
  64
  65 /*! Print the generic code to a `std::ostream &`.
  66 */
  67 inline std::ostream &operator<<(std::ostream &s, const generic_code &v)
  68 {
  69   if(v.empty())
  70   {
  71     return s << "(empty)";
  72   }
  73   return s << v.domain().name().c_str() << ": " << v.message().c_str();
  74 }
  75
  76 BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_END
  77
  78 #endif