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std::chrono...ating_point(3)   C++ Standard Libary  std::chrono...ating_point(3)

NAME
     std::chrono::treat_as_floating_point - std::chrono::treat_as_floating_point

Synopsis
	Defined in header <chrono>
	template< class Rep >						  (since
     C++11)
	struct treat_as_floating_point : std::is_floating_point<Rep> {};

	The  std::chrono::treat_as_floating_point trait helps determine if a du-
     ration can be
	converted to another duration with a different tick period.

	Implicit conversions between two durations normally depends on the  tick
     period of
	the  durations.  However,  implicit conversions can happen regardless of
     tick period if
	std::chrono::treat_as_floating_point<Rep>::value == true.

Specializations
	std::chrono::treat_as_floating_point may be specialized for  program-de-
     fined types.

Example
     // Run this code

      #include <chrono>
      #include <iostream>
      #include <thread>

      void timed_piece_of_code()
      {
	  std::chrono::milliseconds simulated_work(2);
	  std::this_thread::sleep_for(simulated_work);
      }

      int main()
      {
	  auto start = std::chrono::high_resolution_clock::now();

	  std::cout << "Running some timed piece of code...\n";
	  timed_piece_of_code();

	  auto stop = std::chrono::high_resolution_clock::now();

	  // A floating point milliseconds type
	  using FpMilliseconds =
	      std::chrono::duration<float, std::chrono::milliseconds::period>;

	  static_assert(std::chrono::treat_as_floating_point<FpMillisec-
     onds::rep>::value,
			"Rep required to be floating point");

	  // Note that implicit conversion is not allowed here
	  auto i_ms = std::chrono::duration_cast<std::chrono::milliseconds>(stop
     - start);

	  // Note that implicit conversion is allowed here
	  auto f_ms = FpMilliseconds(stop - start);

	  std::cout << "Timing stats:\n";

	  std::cout << "  Time in milliseconds, using default rep: "
		    << i_ms.count() << '\n';

	  std::cout << "  Time in milliseconds, using floating point rep: "
		    << f_ms.count() << '\n';
      }

Possible output:
      Running some timed piece of code...
      Timing stats:
	Time in milliseconds, using default rep: 2
	Time in milliseconds, using floating point rep: 2.57307

See also
http://cppreference.com 	   2024.06.10	    std::chrono...ating_point(3)
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