;; declare lambda
($ a (-> (x) (* x 2)))
(assert-eq? 14 (a 7))

;; high order function
($ b (-> (x y) (x (x y))))
(assert-eq? 12 (b a 3))

;; calling function literal
(assert-eq? 7 ( (-> (x y) (+ x y 1)) 2 4 ))

;; syntaxic sugar for function declaration
($ (c n) (* 2 n))
(assert-eq? 18 (c 9))

;; inner variable
($ (d x) ($ y 3) (+ x y))
(assert-eq? 7 (d 4))