23 General utilities library [utilities]

23.17 Time utilities [time]

template <class Rep>
struct duration_values {
public:
  static constexpr Rep zero();
  static constexpr Rep min();
  static constexpr Rep max();
};

The duration template uses the duration_values trait to construct special values of the durations representation (Rep).

This is done because the representation might be a class type with behavior which requires some other implementation to return these special values.

In that case, the author of that class type should specialize duration_values to return the indicated values.

static constexpr Rep zero();

Returns: Rep(0).

Rep(0) is specified instead of Rep() because Rep() may have some other meaning, such as an uninitialized value.

— end note

]

Remarks: The value returned shall be the additive identity.

static constexpr Rep min();

Returns: numeric_limits<Rep>::lowest().

Remarks: The value returned shall compare less than or equal to zero().

static constexpr Rep max();

Returns: numeric_limits<Rep>::max().

Remarks: The value returned shall compare greater than zero().