std::chrono::duration<Rep,Period>::operator++, std::chrono::duration<Rep,Period>::operator--

(1) 
duration& operator++();
 (until C++17) 
constexpr duration& operator++();
 (since C++17)
(2) 
duration operator++(int);
 (until C++17) 
constexpr duration operator++(int);
 (since C++17)
(3) 
duration& operator--();
 (until C++17) 
constexpr duration& operator--();
 (since C++17)
(4) 
duration operator--(int);
 (until C++17) 
constexpr duration operator--(int);
 (since C++17)

Increments or decrements the number of ticks for this duration.

If rep_ is a member variable holding the number of ticks in a duration object,

1) Equivalent to ++rep_; return *this;
2) Equivalent to return duration(rep_++)
3) Equivalent to --rep_; return *this;
4) Equivalent to return duration(rep_--);

Parameters

(none).

Return value

1,3) a reference to this duration after modification
2,4) a copy of the duration made before modification

Example

#include <chrono>
#include <iostream>
 
int main()
{
    std::chrono::hours h(1);
    std::chrono::minutes m = ++h;
    m--;
    std::cout << m.count() << " minutes\n";
}

Output:

119 minutes

See also

implements compound assignment between two durations
(public member function)
implements arithmetic operations with durations as arguments
(function template)

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