This gem allows you to guard methods that have side effects with a callback that fires before the method is invoked. If the callback returns a “falsey” value, the method is halted and will not be called, and the result will be nil instead. if the method does not have side effects or you depend on its return value, you should NOT use this on that method! This will break the hell out of design by contract. Currently does not work with methods that accept blocks so be aware of that. Fixes, improvements, pull requests, and general “why on earth did you do this” notes are encouraged.