experimental/status-code/iostream_support.hpp

0001 /* Proposed SG14 status_code
0002 (C) 2018-2024 Niall Douglas <http://www.nedproductions.biz/> (5 commits)
0003 File Created: Feb 2018
0004
0005
0006 Boost Software License - Version 1.0 - August 17th, 2003
0007
0008 Permission is hereby granted, free of charge, to any person or organization
0009 obtaining a copy of the software and accompanying documentation covered by
0010 this license (the "Software") to use, reproduce, display, distribute,
0011 execute, and transmit the Software, and to prepare derivative works of the
0012 Software, and to permit third-parties to whom the Software is furnished to
0013 do so, all subject to the following:
0014
0015 The copyright notices in the Software and this entire statement, including
0016 the above license grant, this restriction and the following disclaimer,
0017 must be included in all copies of the Software, in whole or in part, and
0018 all derivative works of the Software, unless such copies or derivative
0019 works are solely in the form of machine-executable object code generated by
0020 a source language processor.
0021
0022 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
0023 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
0024 FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
0025 SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
0026 FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
0027 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
0028 DEALINGS IN THE SOFTWARE.
0029 */
0030
0031 #ifndef BOOST_OUTCOME_SYSTEM_ERROR2_IOSTREAM_SUPPORT_HPP
0032 #define BOOST_OUTCOME_SYSTEM_ERROR2_IOSTREAM_SUPPORT_HPP
0033
0034 #include "error.hpp"
0035
0036 #include <ostream>
0037
0038 BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_BEGIN
0039
0040 /*! Print the status code to a `std::ostream &`.
0041 Requires that `DomainType::value_type` implements an `operator<<` overload for `std::ostream`.
0042 */
0043 BOOST_OUTCOME_SYSTEM_ERROR2_TEMPLATE(class DomainType)  //
0044 BOOST_OUTCOME_SYSTEM_ERROR2_TREQUIRES(BOOST_OUTCOME_SYSTEM_ERROR2_TPRED(
0045 std::is_same<std::ostream,
0046              typename std::decay<decltype(std::declval<std::ostream>() << std::declval<typename status_code<DomainType>::value_type>())>::type>::value))
0047 inline std::ostream &operator<<(std::ostream &s, const status_code<DomainType> &v)
0048 {
0049   if(v.empty())
0050   {
0051     return s << "(empty)";
0052   }
0053   return s << v.domain().name().c_str() << ": " << v.value();
0054 }
0055
0056 /*! Print a status code domain's `string_ref` to a `std::ostream &`.
0057  */
0058 inline std::ostream &operator<<(std::ostream &s, const status_code_domain::string_ref &v)
0059 {
0060   return s << v.c_str();
0061 }
0062
0063 /*! Print the erased status code to a `std::ostream &`.
0064  */
0065 template <class ErasedType> inline std::ostream &operator<<(std::ostream &s, const status_code<detail::erased<ErasedType>> &v)
0066 {
0067   if(v.empty())
0068   {
0069     return s << "(empty)";
0070   }
0071   return s << v.domain().name() << ": " << v.message();
0072 }
0073
0074 /*! Print the generic code to a `std::ostream &`.
0075  */
0076 inline std::ostream &operator<<(std::ostream &s, const generic_code &v)
0077 {
0078   if(v.empty())
0079   {
0080     return s << "(empty)";
0081   }
0082   return s << v.domain().name() << ": " << v.message();
0083 }
0084
0085 BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE_END
0086
0087 #endif