Rules
phil/recurrenceRecurrenceRule::parse() reads a rule as RFC 5545 writes it, with or without RRULE:, its parts in any order and
case; (string) $rule writes it back, its parts in a fixed order, those with their default left out.
$rule = RecurrenceRule::parse('rrule:freq=weekly;interval=2;byday=mo,we;until=20261231T235959Z');
(string) $rule; // "FREQ=WEEKLY;INTERVAL=2;UNTIL=20261231T235959Z;BYDAY=MO,WE"| Part | Holds |
|---|---|
FREQ | YEARLY, MONTHLY, WEEKLY or DAILY |
INTERVAL | Every so many periods, 1 by default |
COUNT, UNTIL | So many occurrences, or the last moment one may start: a day (20261231), a UTC time (…T235959Z), or a floating time read in the time zone given to parse() |
BYDAY | Weekdays, with their place in the month or the year in monthly and yearly rules: MO, 2TU, -1FR |
BYMONTHDAY | Days of the month, from the end when negative: 1, 15, -1 |
BYMONTH | Months, 1 to 12 |
BYSETPOS | The places, in each period, of the days the other parts keep: -1, the last |
WKST | The day weeks start on, Monday by default |
RecurrenceRule::of() builds one from its parts.
What is checked
As RFC 5545 asks, a rule is refused with InvalidRule for: an interval or a count under 1; both a count and an end;
an end day without its end; a place in the month or year in a weekly or daily rule, beyond 5 in a monthly one, beyond
53 or 0 anywhere; month days in a weekly rule, beyond 31 or 0; months outside 1 to 12; set positions beyond 366 or 0,
or without another BY part. Hourly and finer frequencies, BYHOUR, BYMINUTE, BYSECOND, BYWEEKNO and
BYYEARDAY are not read: InvalidRule names them.
of() and parse() refuse the same rules, so that every rule written as text is read back: an interval or a count
above RecurrenceRule::MAX_NUMBER, 9999, the four digits parse() reads; an end outside the years 1 to 9999, in UTC
for an end time and as it is for an end day, since UNTIL writes its year with four digits. A rule a form or an
import builds can thus be stored and hydrated again.