Create Function Composition

Author: letsdeepchat

Function Composition

@@ -0,0 +1,21 @@
+/**
+ * @param {Function[]} functions
+ * @return {Function}
+ */
+var compose = function(functions) {
+    if( functions.length === 0) {
+        return function(x) {
+            return x;
+        };
+    }
+    return functions.reduceRight(function(prevFn, nextFn) {
+        return function(x) {
+            return nextFn(prevFn(x));
+        };
+    });
+};
+
+/**
+ * const fn = compose([x => x + 1, x => 2 * x])
+ * fn(4) // 9
+ */