A parsed recurrence rule (RRULE). This is the transparent record returned by Ical.Parser for reading parsed rule data. For constructing rules for generation, use Ical.Generator.Rule and its builder functions.

{ frequency = Weekly { every = 1, weekStart = Time.Mon }
, end = Forever
, byDay = [ every Time.Mon ]
, byMonthDay = []
, byMonth = []
, bySetPos = []
, byHour = []
, byMinute = []
, bySecond = []
, byYearDay = []
, byWeekNo = []
}

• byDay — which days of the week (with optional ordinals for monthly/yearly).
• byMonthDay — which days of the month (1–31, or -31 to -1 from month end).
• byMonth — which months.
• bySetPos — pick the Nth result from the set produced by the other by* parts within each frequency period. Positive counts from the start, negative from the end. For example, BYDAY=MO,TU,WE,TH,FR with bySetPos = [ -1 ] means "the last weekday" of each period.
• byHour — which hours (0–23).
• byMinute — which minutes (0–59).
• bySecond — which seconds (0–60, 60 for leap second).
• byYearDay — which days of the year (1–366, or -366 to -1 from year end).
• byWeekNo — which ISO week numbers (1–53, or -53 to -1 from year end).

When the recurrence stops. Count and Until* are mutually exclusive per RFC 5545 Section 3.3.10.

How often the event recurs. Each variant carries its own configuration:

• every — the interval between occurrences (e.g. every = 2 with Weekly means every other week). Must be at least 1.
• weekStart — which day begins the week (only meaningful for Weekly).

A day-of-week specifier for recurrence rules.

Create one with every, nth, or the convenience helpers like second and last.

-- every Monday
every Time.Mon


-- the 2nd Sunday of the month
second Time.Sun


-- the last Friday
last Time.Fri

Positive ordinals count from the start of the period. Negative ordinals count from the end. nth accepts -53..-1 and 1..53, matching the RFC grammar for numeric BYDAY values.

Match every instance of the given weekday.

Match the nth instance of a weekday.

Positive values count from the start, negative values count from the end, and 0 is invalid.

nth 20 Time.Mon


nth -1 Time.Fri

Extract the weekday from a DaySpec.

Extract the ordinal from a DaySpec, if present.

The 1st instance of a weekday.

The 2nd instance of a weekday.

The 3rd instance of a weekday.

The 4th instance of a weekday.

The 5th instance of a weekday.

The last instance of a weekday.

The 2nd-to-last instance of a weekday.

The 3rd-to-last instance of a weekday.

The 4th-to-last instance of a weekday.

The 5th-to-last instance of a weekday.