std::chrono::time_point<Clock,Duration>::operator+=, operator-=
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                    < cpp | chrono | time point
                    
                                                            
                    |   time_point& operator+=( const duration& d );  | 
(1) |  (since C++11)  (constexpr since C++17)  | 
|   time_point& operator-=( const duration& d );  | 
(2) |  (since C++11)  (constexpr since C++17)  | 
Modifies the time point by the given duration.
1) Applies the offset d to 
pt. Effectively, d is added to the internally stored duration d_ as d_ += d.2) Applies the offset d to 
pt in negative direction. Effectively, d is subtracted from internally stored duration d_ as d_ -= d.Parameters
| d | - | a time offset to apply | 
Return value
*this
Exceptions
May throw implementation-defined exceptions.
Example
| This section is incomplete Reason: no example  | 
See also
|    (C++11)  | 
  performs add and subtract operations involving a time point  (function template)  |