module Period:sig
..end
A period represents the time passed between two events (a date, a time...).
Only an interface defining arithmetic operations on periods is defined here.
An implementation of this interface depends on the kind of an event (see
module Time.Period
, Date.Period
and Calendar.Period
).
typedate_field =
[ `Day | `Month | `Week | `Year ]
module type S =sig
..end
Common interface for all periods.