init commit

stubs/calendar.clj

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+(ns calendar
+  "Erlang :calendar module — date and time calculations.
+
+   In CljElixir: (calendar/local-time), (calendar/universal-time), etc.
+   Works with Erlang date/time tuples: {Year Month Day} and {Hour Min Sec}.")
+
+(defn local-time
+  "Returns the current local datetime as {{Y M D} {H M S}}.
+   (calendar/local-time) ;=> {{2024 3 9} {12 30 0}}"
+  [])
+
+(defn universal-time
+  "Returns the current UTC datetime as {{Y M D} {H M S}}.
+   (calendar/universal-time) ;=> {{2024 3 9} {12 30 0}}"
+  [])
+
+(defn local-time-to-universal-time-dst
+  "Converts local time to UTC, handling DST. Returns list of possible results."
+  [datetime])
+
+(defn universal-time-to-local-time
+  "Converts UTC to local time."
+  [datetime])
+
+(defn now-to-datetime
+  "Converts erlang:now/0 tuple to datetime tuple."
+  [now])
+
+(defn now-to-local-time
+  "Converts erlang:now/0 to local datetime."
+  [now])
+
+(defn now-to-universal-time
+  "Converts erlang:now/0 to UTC datetime."
+  [now])
+
+(defn datetime-to-gregorian-seconds
+  "Converts {{Y M D} {H M S}} to Gregorian seconds (since year 0).
+   (calendar/datetime-to-gregorian-seconds {{2024 1 1} {0 0 0}}) ;=> 63871..."
+  [datetime])
+
+(defn gregorian-seconds-to-datetime
+  "Converts Gregorian seconds back to {{Y M D} {H M S}}.
+   (calendar/gregorian-seconds-to-datetime 63871...)"
+  [seconds])
+
+(defn date-to-gregorian-days
+  "Converts {Year Month Day} to Gregorian day count.
+   (calendar/date-to-gregorian-days {2024 1 1})"
+  ([date])
+  ([year month day]))
+
+(defn gregorian-days-to-date
+  "Converts Gregorian day count to {Year Month Day}."
+  [days])
+
+(defn day-of-the-week
+  "Returns day of week (1=Monday, 7=Sunday).
+   (calendar/day-of-the-week {2024 3 9}) ;=> 6"
+  ([date])
+  ([year month day]))
+
+(defn is-leap-year
+  "Returns true if year is a leap year.
+   (calendar/is-leap-year 2024) ;=> true"
+  [year])
+
+(defn last-day-of-the-month
+  "Returns the last day of the month.
+   (calendar/last-day-of-the-month 2024 2) ;=> 29"
+  [year month])
+
+(defn valid-date
+  "Returns true if the date is valid.
+   (calendar/valid-date {2024 2 29}) ;=> true"
+  ([date])
+  ([year month day]))
+
+(defn iso-week-number
+  "Returns {year week} for a date.
+   (calendar/iso-week-number {2024 3 9}) ;=> {2024 10}"
+  ([date])
+  ([year month day]))
+
+(defn time-difference
+  "Returns the time difference between two datetimes.
+   (calendar/time-difference dt1 dt2) ;=> {days {hours mins secs}}"
+  [datetime1 datetime2])
+
+(defn seconds-to-daystime
+  "Converts seconds to {days {hours minutes seconds}}.
+   (calendar/seconds-to-daystime 90061) ;=> {1 {1 1 1}}"
+  [seconds])
+
+(defn seconds-to-time
+  "Converts seconds to {hours minutes seconds}.
+   (calendar/seconds-to-time 3661) ;=> {1 1 1}"
+  [seconds])
+
+(defn time-to-seconds
+  "Converts {hours minutes seconds} to seconds.
+   (calendar/time-to-seconds {1 1 1}) ;=> 3661"
+  [time])
+
+(defn system-time-to-local-time
+  "Converts system time to local datetime."
+  [time unit])
+
+(defn system-time-to-universal-time
+  "Converts system time to UTC datetime."
+  [time unit])
+
+(defn rfc3339-to-system-time
+  "Parses RFC 3339 timestamp to system time.
+   (calendar/rfc3339-to-system-time \"2024-03-09T12:00:00Z\") ;=> integer"
+  ([string])
+  ([string opts]))
+
+(defn system-time-to-rfc3339
+  "Converts system time to RFC 3339 string.
+   (calendar/system-time-to-rfc3339 time) ;=> \"2024-03-09T12:00:00Z\""
+  ([time])
+  ([time opts]))