Function: calendar-leap-year-p

calendar-leap-year-p is a byte-compiled function defined in calendar.el.gz.

Signature

(calendar-leap-year-p YEAR)

Documentation

Return t if YEAR is a Gregorian leap year.

A negative year is interpreted as BC; -1 being 1 BC, and so on.

Source Code

;; Defined in /usr/src/emacs/lisp/calendar/calendar.el.gz
(defsubst calendar-leap-year-p (year)
  "Return t if YEAR is a Gregorian leap year.
A negative year is interpreted as BC; -1 being 1 BC, and so on."
  ;; 1 BC = 0 AD, 2 BC acts like 1 AD, etc.
  (if (< year 0) (setq year (1- (abs year))))
  (and (zerop (% year 4))
       (or (not (zerop (% year 100)))
           (zerop (% year 400)))))