std::literals::chrono_literals::operator""s

 

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std::chrono::duration

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duration::duration
duration::operator=
duration::count
duration::zero
duration::min
duration::max
duration::operator+duration::operator-
duration::operator++duration::operator--
duration::operator+=duration::operator-=duration::operator*=duration::operator/=duration::operator%=
Non-member functions
operator+operator-operator*operator/operator% operator==operator!=operator<operator<=operator>operator>=	common_type duration_cast operator""h (C++14) operator""min (C++14) operator""s (C++14) operator""ms (C++14) operator""us (C++14) operator""ns (C++14)
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Defined in header <chrono>
constexpr chrono::seconds operator "" s(unsigned long long secs);	(1)	(since C++14)
constexpr chrono::duration</*unspecified*/> operator "" s(long double secs);	(2)	(since C++14)

Forms a std::chrono::duration literal representing seconds.

1) integer literal, returns exactly std::chrono::seconds(secs)

2) floating-point literal, returns a floating-point duration equivalent to std::chrono::seconds

Parameters

secs

-

the number of seconds

Return value

The std::chrono::duration literal.

Possible implementation

constexpr std::chrono::seconds operator ""s(unsigned long long s) { return std::chrono::seconds(s); } constexpr std::chrono::duration<long double> operator ""s(long double s) { return std::chrono::duration<long double>(s); }

Notes

These operators are declared in the namespace std::literals::chrono_literals, where both literals and chrono_literals are inline namespaces. Access to these operators can be gained with using namespace std::literals and using namespace std::literals::chrono_literals.

In addition, within the namespace std::chrono, the directive using namespace literals::chrono_literals; is provided by the standard library, so that if a programmer uses using namespace std::chrono; to gain access to the duration classes, the duration literal operators become visible as well.

std::string also defines operator""s, to represent literal objects of type std::string, but it is a string literal: 10s is ten seconds, but "10"s is a two-character string.

Example

Run this code

#include <iostream>
#include <chrono>
 
int main()
{
    using namespace std::literals::chrono_literals;
    auto halfmin = 30s;
    std::cout << "half a minute is " << halfmin.count() << " seconds\n"
              << "a minute and a half is " << (1min + 30s).count() << " seconds\n";
}

Output:

half a minute is 30 seconds
a minute and a half is 90 seconds

See also

(constructor)

constructs new duration (public member function of std::chrono::duration)