Schyntax is a domain-specific language for defining event schedules in a terse, but readable, format. For example, if you want something to run every five minutes during work hours on weekdays, you could write days(mon..fri) hours(9..<17) min(*%5). This project is the reference implementation of Schyntax.

This library is NOT a scheduled task runner. Most likely, you'll want to use Schtick, which is a scheduled task runner built on top of Schyntax, instead of using this library directly.

Schyntax exposes the Schedule class.

using Schyntax;

var sch = new Schedule("min(*%2)");

Accepts an optional after argument in the form of a DateTime. If no argument is provided, the current time is used.

Returns a DateTime object representing the next timestamp which matches the scheduling criteria. The date will always be greater than, never equal to, after. If no timestamp could be found which matches the scheduling criteria, a ValidTimeNotFoundException error is thrown, which generally indicates conflicting scheduling criteria (explicitly including and excluding the same day or time).

var nextEventTime = sch.Next();

Same as Previous() accept that its return value will be less than or equal to the current time or optional atOrBefore argument. This means that if you want to find the last n-previous events, you should subtract at least a millisecond from the result before passing it back to the function.

var prevEventTime = sch.Previous();