fix some file extensions

Task/First-class-functions/CoffeeScript/first-class-functions.coffee

@@ -0,0 +1,13 @@
+# Functions as values of a variable
+cube = (x) -> Math.pow x, 3
+cuberoot = (x) -> Math.pow x, 1 / 3
+
+# Higher order function
+compose = (f, g) -> (x) -> f g(x)
+
+# Storing functions in a array
+fun = [Math.sin, Math.cos, cube]
+inv = [Math.asin, Math.acos, cuberoot]
+
+# Applying the composition to 0.5
+console.log compose(inv[i], fun[i])(0.5) for i in [0..2]​​​​​​​