September 2017 Update

Task/Function-composition/JavaScript/function-composition-5.js

@@ -0,0 +1,19 @@
+(() => {
+    'use strict';
+
+    // compose :: (a -> b) -> (b -> c) -> (a -> c)
+    const compose = (f, g) => x => g(f(x));
+
+
+    // TEST
+    const
+        sqrt = Math.sqrt,
+        succ = x => x + 1,
+        half = x => x / 2;
+
+    const
+        succSqrt = compose(sqrt, succ),
+        halfSuccSqrt = compose(succSqrt, half);
+
+    return halfSuccSqrt(5);
+})();