std::chrono::time_point<Clock,Duration>::time_point

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C-style date and time
 
std::chrono::time_point
 
(1)
time_point();
 (since C++11)
(until C++14)
constexpr time_point();
 (since C++14)
(2)
explicit time_point( const duration& d );
 (since C++11)
(until C++14)
constexpr explicit time_point( const duration& d );
 (since C++14)
(3)
template< class Duration2 >
time_point( const time_point<Clock,Duration2>& t );
 (since C++11)
(until C++14)
template< class Duration2 >
constexpr time_point( const time_point<Clock,Duration2>& t );
 (since C++14)

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::high_resolution_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).count() << " ms\n";
}
 
int main() 
{
    const TimePoint default_value = TimePoint(); // (1)
    print_ms(default_value); // 0 ms
 
    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); // 4000 ms
 
    const TimePoint time_point_now = Clock::now(); // (3)
    print_ms(time_point_now); // 43098276 ms
}

Possible output: 

0 ms
4000 ms
43098276 ms

See also

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