A subtrait of RangeBounds<T> where T is Copy + Default + Step
that turns implementers of it into an instance of DecBy when
dec_by is called. Currently, the blanket implementation of this
trait exported from the crate for RangeBounds is the only possible useful implementation, but
it was decided not to make it a “sealed” trait in case additional methods are added in the
future that would be implementable by end-user code in a meaningfully varied way.
A subtrait of RangeBounds<T> where T is Copy + Default + Step
that turns implementers of it into an instance of IncBy when
inc_by is called. Currently, the blanket implementation of this
trait exported from the crate for RangeBounds is the only possible useful implementation, but
it was decided not to make it a “sealed” trait in case additional methods are added in the
future that would be implementable by end-user code in a meaningfully varied way.