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Task/First-class-functions/EchoLisp/first-class-functions.echolisp

@@ -0,0 +1,15 @@
+;; adapted from Racket
+;; (compose f g h ... ) is a built-in defined as :
+;; (define (compose f g) (λ (x) (f (g x))))
+
+(define (cube x) (expt x 3))
+(define (cube-root x) (expt x (// 1 3)))
+(define funlist (list sin cos cube))
+(define ifunlist (list asin acos cube-root))
+
+(for ([f funlist] [i ifunlist])
+  (writeln ((compose i f) 0.5)))
+→
+    0.5
+    0.4999999999999999
+    0.5