id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
11631	boost chrono io v2 does not let you support custom clocks	Sébastien Barthélémy <barthelemy@…>	viboes	"v1 lets you specialize struct clock_string in order to add support for a custom clock.

I could not find a way to do the equivalent with v2. If confirmed, that would also mean that boost chrono io canot support std::chrono clocks.


Attached is a minimalistic example showing a custom clock with chrono io v1 support. The code does not compile under v2.

Compilation result with boost 1.58
{{{
$ make clean && make test
rm -f src/*.o src/chrono_io
clang++ -std=c++11 -c -g -fPIC -Iinclude -I/usr/include -o src/chrono_io.o src/chrono_io.cc
clang++ -std=c++11 -rdynamic -Lsrc -o src/chrono_io src/chrono_io.o -lboost_chrono -lboost_system -L/usr/lib/x86_64-linux-gnu
LD_LIBRARY_PATH=/usr/lib/x86_64-linux-gnu ./src/chrono_io
1402372272646902866 nanoseconds since year 2k
}}}

idem with #define BOOST_CHRONO_DONT_PROVIDES_DEPRECATED_IO_SINCE_V2_0_0
{{{
$ make clean && make test
rm -f src/*.o src/chrono_io
clang++ -std=c++11 -c -g -fPIC -Iinclude -I/usr/include -o src/chrono_io.o src/chrono_io.cc
In file included from src/chrono_io.cc:4:
In file included from /usr/include/boost/chrono/chrono_io.hpp:26:
In file included from /usr/include/boost/chrono/io/time_point_io.hpp:22:
In file included from /usr/include/boost/chrono/io/time_point_put.hpp:15:
/usr/include/boost/chrono/io/time_point_units.hpp:77:16: error: no matching member function for call to 'do_get_epoch'
        return do_get_epoch(Clock());
               ^~~~~~~~~~~~
/usr/include/boost/chrono/io/time_point_put.hpp:236:42: note: in instantiation of function template specialization
      'boost::chrono::time_point_units<char>::get_epoch<MyMillenniumClock>' requested here
        string_type str = facet.template get_epoch<Clock>();
                                         ^
/usr/include/boost/chrono/io/time_point_put.hpp:134:19: note: in instantiation of function template specialization
      'boost::chrono::time_point_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put_epoch<MyMillenniumClock>' requested
      here
              s = put_epoch<Clock> (units_facet, s, ios);
                  ^
/usr/include/boost/chrono/io/time_point_put.hpp:170:18: note: in instantiation of function template specialization
      'boost::chrono::time_point_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put<MyMillenniumClock,
      boost::chrono::duration<long, boost::ratio<1, 1000000000> > >' requested here
          return put(facet, i, ios, fill, tp, str.data(), str.data() + str.size());
                 ^
/usr/include/boost/chrono/io/time_point_io.hpp:662:44: note: in instantiation of function template specialization
      'boost::chrono::time_point_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put<MyMillenniumClock,
      boost::chrono::duration<long, boost::ratio<1, 1000000000> > >' requested here
              if (time_point_put<CharT> ().put(os, os, os.fill(), tp) .failed())
                                           ^
src/chrono_io.cc:45:15: note: in instantiation of function template specialization 'boost::chrono::operator<<<char, std::char_traits<char>,
      MyMillenniumClock, boost::chrono::duration<long, boost::ratio<1, 1000000000> > >' requested here
    std::cout << MyMillenniumClock::now() << std::endl;
              ^
/usr/include/boost/chrono/io/time_point_units.hpp:92:27: note: candidate function not viable: no known conversion from 'MyMillenniumClock' to
      'boost::chrono::system_clock' for 1st argument
      virtual string_type do_get_epoch(system_clock) const=0;
                          ^
/usr/include/boost/chrono/io/time_point_units.hpp:99:27: note: candidate function not viable: no known conversion from 'MyMillenniumClock' to
      'boost::chrono::steady_clock' for 1st argument
      virtual string_type do_get_epoch(steady_clock) const=0;
                          ^
/usr/include/boost/chrono/io/time_point_units.hpp:107:27: note: candidate function not viable: no known conversion from 'MyMillenniumClock' to
      'boost::chrono::process_real_cpu_clock' for 1st argument
      virtual string_type do_get_epoch(process_real_cpu_clock) const=0;
                          ^
/usr/include/boost/chrono/io/time_point_units.hpp:114:27: note: candidate function not viable: no known conversion from 'MyMillenniumClock' to
      'boost::chrono::process_user_cpu_clock' for 1st argument
      virtual string_type do_get_epoch(process_user_cpu_clock) const=0;
                          ^
/usr/include/boost/chrono/io/time_point_units.hpp:120:27: note: candidate function not viable: no known conversion from 'MyMillenniumClock' to
      'boost::chrono::process_system_cpu_clock' for 1st argument
      virtual string_type do_get_epoch(process_system_cpu_clock) const=0;
                          ^
/usr/include/boost/chrono/io/time_point_units.hpp:126:27: note: candidate function not viable: no known conversion from 'MyMillenniumClock' to
      'boost::chrono::process_cpu_clock' for 1st argument
      virtual string_type do_get_epoch(process_cpu_clock) const=0;
                          ^
/usr/include/boost/chrono/io/time_point_units.hpp:135:27: note: candidate function not viable: no known conversion from 'MyMillenniumClock' to
      'boost::chrono::thread_clock' for 1st argument
      virtual string_type do_get_epoch(thread_clock) const=0;
                          ^
1 error generated.
Makefile:7: recipe for target 'src/chrono_io.o' failed
make: *** [src/chrono_io.o] Error 1
}}}"	Bugs	closed	Boost 1.60.0	chrono	Boost 1.58.0	Problem	fixed