c++ - What are the uses of std::chrono::high_resolution_clock? -


at first thought can used performance measurements. said std::chrono::high_resolution_clock may not steady (is_steady may false). said std::chrono::high_resolution_clock may alias of std::chrono::system_clock not steady. can't measure time intervals type of clock because @ moment clock may adjusted , measurements wrong.

at same time can't convert time points of std::chrono::high_resolution_clock calendar time because doesn't have to_time_t method. can't real time type of clock either.

then can std::chrono::high_resolution_clock used for?

there none.

sorry, my bad.

if tempted use high_resolution_clock, choose steady_clock instead. on libc++ , vs high_resolution_clock type alias of steady_clock anyway.

on gcc high_resolution_clock type alias of system_clock , i've seen more 1 use of high_resolution_clock::to_time_t on platform (which wrong).

do use <chrono>. there parts of <chrono> should avoid.

  • don't use high_resoulution_clock.
  • avoid uses of .count() , .time_since_epoch() unless there no other way job done.
  • avoid duration_cast unless code won't compile without it, , desire truncation-towards-zero behavior.
  • avoid explicit conversion syntax if implicit conversion compiles.

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