# Tweet by [@keefmoon](http://twitter.com/keefmoon) on 2018-10-21 23:50:52 > [!INFO] Archived from [original tweet](http://twitter.com/keefmoon/status/1054158107843137536) Is the there a name and definition for the style of context free grammar that Swift uses in it's documentation? @SwiftLang https://t.co/sMhvSDxiaL