NAME¶

std::chrono::time_point::time_point - std::chrono::time_point::time_point

Synopsis¶

(since C++11)
time_point(); (constexpr since
C++14)
explicit time_point( const (since C++11)
duration& d ); (1) (constexpr
since C++14)
template< class Duration2 > (2) (since C++11)
time_point( const (3) (constexpr
time_point<Clock, Duration2>& since C++14)
t );

Constructs a new time_point from one of several optional data sources.

1) Default constructor, creates a time_point representing the Clock's epoch (i.e.,
time_since_epoch() is zero).
2) Constructs a time_point at Clock's epoch plus d.
3) Constructs a time_point by converting t to duration. This constructor only
participates in overload resolution if Duration2 is implicitly convertible to
duration.

Parameters¶

d - a duration to copy from
t - a time_point to convert from

Example¶

// Run this code

#include <chrono>
#include <iostream>

using Clock = std::chrono::steady_clock;
using TimePoint = std::chrono::time_point<Clock>;

void print_ms(const TimePoint& point)
{
using Ms = std::chrono::milliseconds;
const Clock::duration since_epoch = point.time_since_epoch();
std::cout << std::chrono::duration_cast<Ms>(since_epoch) << '\n';
}

int main()
{
const TimePoint default_value = TimePoint(); // (1)
print_ms(default_value); // 0ms

const Clock::duration duration_4_seconds = std::chrono::seconds(4);
const TimePoint time_point_4_seconds(duration_4_seconds); // (2)
// 4 seconds from start of epoch
print_ms(time_point_4_seconds); // 4000ms

const TimePoint time_point_now = Clock::now(); // (3)
print_ms(time_point_now); // 212178842ms
}

Possible output:¶

0ms
4000ms
212178842ms

See also¶

constructor constructs new duration
(public member function of std::chrono::duration<Rep,Period>)
duration_cast converts a duration to another, with a different tick interval
(C++11) (function template)