std::chrono::duration<Rep,Period>::operator+(unary), (3) - Linux Manuals

std::chrono::duration<Rep,Period>::operator+(unary),: std::chrono::duration<Rep,Period>::operator+(unary),

NAME

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

Synopsis

constexpr duration operator+() const;                    (until C++17)
constexpr std::common_type_t<duration>                   (since C++17)
operator+() const;                               (1)
constexpr duration operator-() const;                                  (until C++17)
constexpr std::common_type_t<duration>               (2)               (since C++17)
operator-() const;

Implements unary plus and unary minus for the durations.

If rep_ is a member variable holding the number of ticks in a duration object, and D
is the return type,

1) Equivalent to return D(*this);
2) Equivalent to return D(-rep_);

Parameters

(none)

Return value

1) a copy of this duration object
2) a copy of this duration object, with the number of ticks negated

Example

// Run this code

 #include <chrono>
 #include <iostream>

 int main()
 {
  std::chrono::seconds s1(10);
  std::chrono::seconds s2 = -s1;

  std::cout << "negated 10 seconds are " << s2.count() << " seconds\n";
 }

Output:

 negated 10 seconds are -10 seconds