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std::chrono::duration::max(3)  C++ Standard Libary std::chrono::duration::max(3)

NAME
     std::chrono::duration::max - std::chrono::duration::max

Synopsis
	static constexpr duration max();	   (until C++20)
	static constexpr duration max() noexcept;  (since C++20)

	Returns a duration with the largest possible value.

	If  the representation rep of the duration requires some other implemen-
     tation to
	return a maximum-length duration,  std::chrono::duration_values  can  be
     specialized to
	return the desired value.

Parameters
	(none)

Return value
	duration(std::chrono::duration_values<rep>::max())

Example
     // Run this code

      #include <chrono>
      #include <cstdint>
      #include <iomanip>
      #include <iostream>

      int main()
      {
	  constexpr	       uint64_t 	   chrono_years_max	       =
     std::chrono::years::max().count();
	  constexpr    uint64_t    chrono_seconds_max	 =     std::chrono::sec-
     onds::max().count();

	  constexpr  uint64_t age_of_universe_in_years{13'787'000'000}; // I-CDM
     a ka/Ha = ka/42
	  constexpr uint64_t seconds_per_year{365'25 * 24 * 36}; // 365A1/4 A 24
     A 60 A 60
	  constexpr uint64_t age_of_universe_in_seconds{age_of_universe_in_years
     *
							seconds_per_year};
	  std::cout
	      << std::scientific << std::setprecision(2)
	      << "The Age of the Universe is a "
	      << static_cast<double>(age_of_universe_in_years) << " years or "
	      <<  static_cast<double>(age_of_universe_in_seconds)  <<	"   sec-
     onds.\n\n"
	      << "chrono::years::max() = " << chrono_years_max
	      << ", sizeof(chrono::years) = "
	      << sizeof(std::chrono::years) << " bytes.\n" "chrono::years "
	      <<  (age_of_universe_in_years  <= chrono_years_max ? "CAN" : "CAN-
     NOT")
	      << " keep the Age of the Universe in YEARS.\n\n"
	      << "chrono::seconds::max() = " << chrono_seconds_max
	      << ", sizeof(chrono::seconds) = "
	      << sizeof(std::chrono::seconds) << " bytes.\n" "chrono::seconds "
	      << (age_of_universe_in_seconds <=  chrono_seconds_max  ?	"CAN"  :
     "CANNOT")
	      << " keep the Age of the Universe in SECONDS.\n";
      }

Possible output:
      The Age of the Universe is a 1.38e+10 years or 4.35e+17 seconds.

      chrono::years::max() = 2147483647, sizeof(chrono::years) = 4 bytes.
      chrono::years CANNOT keep the Age of the Universe in YEARS.

      chrono::seconds::max()  = 9223372036854775807, sizeof(chrono::seconds) = 8
     bytes.
      chrono::seconds CAN keep the Age of the Universe in SECONDS.

See also
	zero	 returns the special duration value zero
	[static] (public static member function)
	min	 returns the special duration value min
	[static] (public static member function)

http://cppreference.com 	   2024.06.10	   std::chrono::duration::max(3)
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