date-seqs.clj

(import '(org.joda.time LocalDate))

(defn today [] (LocalDate.))

;; basic functions to increment or decrement a date
(defn inc-date [#^LocalDate ds] (.plusDays ds 1))
(defn dec-date [#^LocalDate ds] (.minusDays ds 1))

;; generate infinite streams of LocalDate objects starting with start-ds
(defn inc-date-stream [#^LocalDate start-ds] (iterate inc-date start-ds))
(defn dec-date-stream [#^LocalDate start-ds] (iterate dec-date start-ds))

is-weekend.clj

(defn weekend? [#^LocalDate ds] (> (.get (.dayOfWeek ds)) 5))

(take 50 (filter weekend? (inc-date-stream (today))))