Changelog

All notable changes to phil/recurrence will be documented in this file.

Updates should follow the Keep a CHANGELOG principles.

NEXT - YYYY-MM-DD

Added

• Frequency, Weekday, WeekdayNum, RecurrenceRule; RecurrenceException and InvalidRule. RecurrenceRule::of() refuses what parse() cannot read back — an interval or a count above MAX_NUMBER, 9999, an end outside the years 1 to 9999 —, so that every rule written as text is read again.
• Recurrence, which lays out a period with its days as numbers, builds a date only for a day it keeps, and reads its exceptions once. between() and next() reach the period of their window by arithmetic when the rule has no COUNT, and between() stops at the period of its last moment. MAX_PERIODS counts only periods in a row that match no day, so an endless rule runs as long as it matches. The occurrences stop at the end of the year 9999, a rule ending on its last day (UNTIL=99991231) included. between() and next() walk no more than MAX_WALKED periods a call, so that a rule matching one day in years costs a bounded time. The dates RDATE adds, given to of(), are merged into the occurrences in order, once each, counted in neither COUNT nor UNTIL, and taken away by an exception like any occurrence; the exceptions are looked up by instant in a set.
• RecurrenceDates: an RDATE or EXDATE line read — whole days, UTC times, times with TZID, floating times read in a zone given, folded or not — and written back; periods are refused, and a line holds at most MAX_DATES dates in MAX_LENGTH bytes. Its fuzz target, recurrence-dates, checks that a line written back is read again the same.
• SchemaOrg: the schema.org form of the library's value, to embed in JSON-LD; it writes the endDate of an end time as the day it falls on in the first occurrence's time zone.
• The documentation in doc/, one file per topic, indexed by the README.
• CONTRIBUTING.md, SECURITY.md and CODE_OF_CONDUCT.md.