std::chrono::duration<Rep,Period>::max

Since C++20

Returns a duration with the largest possible value.

# Declarations

static constexpr duration max();

(until C++20)

static constexpr duration max() noexcept;

(since C++20)

# Return value

duration(std::chrono::duration_values::max())

# Example

#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::seconds::max().count();
 
    constexpr uint64_t age_of_universe_in_years{13'787'000'000}; // Λ-CDM ≈ k₁/H₀ = k₂/42
    constexpr uint64_t seconds_per_year{365'25 * 24 * 36}; // 365¼ × 24 × 60 × 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 ≈ "
        << static_cast<double>(age_of_universe_in_years) << " years or "
        << static_cast<double>(age_of_universe_in_seconds) << " seconds.\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" : "CANNOT")
        << " 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";
}

# See also