README.md in strong_json-0.6.0 vs README.md in strong_json-0.7.0

@@ -116,13 +116,14 @@
 * `numeric?`
 * `symbol?`
 * `literal?(lit)`
 * `any?`
 
-Shorthands for `optional(array(ty))` and `optional(object(fields))` are also defined as the following:
+Shortcuts for complex data are also defined as the following:
 
-* `array?(ty)`
-* `object?(fields)`
+* `optional(array(ty))` → `array?(ty)`
+* `optional(object(fields))` → `object?(fields)`
+* `optional(enum(types))` → `enum?(types)`
 
 ## Contributing
 
 1. Fork it ( https://github.com/soutaro/strong_json/fork )
 2. Create your feature branch (`git checkout -b my-new-feature`)