Destructuring Examples.clj

;;; All Kinds of Destructuring ;;;

(let [foo 1] foo) 
; => 1

(let [[foo bar] [1 2 3]] [foo bar]) 
; => [1 2]

(let [[foo bar & baz] [1 2 3]] [foo bar baz])
; => [1 2 (3)]

(let [{:keys [foo bar]} {:a 1, :b 2,}] [foo bar])
; => [1 2]

(let [h {:a 1, :b 2, :c 3, :d 4}] [(keys h) (vals h)])
; => [(:d :c :b :a) (4 3 2 1)]

;; d is the whole input collection [1 2 3 4]
(let [[a b c :as d] [1 2 3 4]] d)
; => [1 2 3 4]

(let [[a b c :as d] [1 2 3 4]] [a b c])
; => [1 2 3]

;; thanks, chouser.
(let [[a :as [b :as [c & [d]]]] [1 2]] [a b c d])
; => [1 1 1 2]