Add more higher order functions

higher-order.roc

@@ -6,10 +6,17 @@ app "higher-order"
 main : Task.Task {} I32
 main =
     fn1 = bind Num.sub 3
-    fn2 = bindL Num.sub 3
-    fn3 = compose fn2 fn1
+    fn2 = bindL Num.mul 3
+    fn3 = compose fn1 fn2
+    fn4 = compose fn2 fn1
+    fn5 = compose (compose fn1 fn2) (compose fn3 fn4)
+    fn6 : F64 -> Int a
+    fn6 =
+        (\n -> n)
+        |> compose Num.sqrt
+        |> compose Num.ceiling
     results =
-        [fn1 2, fn2 2, fn3 2]
+        [fn1 2, fn2 2, fn3 2, fn4 2, fn5 2, fn6 9]
         |> List.map Num.toStr
         |> List.mapWithIndex \e, idx -> "fn$(Num.toStr idx) -> $(e)"
         |> Str.joinWith "\n"