I happened to be working on a Singleton class in ruby and just remembered the way it works in factory_girl. They worked it out so you can use both the long way Factory.create(...) and the short way Factory(...) I thought about it and was curious to see how they made the class Factory also behave like a method.

They simply used Factory twice like so:

def Factory (args)
  ...
end

class Factory
  ...
end

My Question is: How does ruby accomplish this? and Is there danger in using this seemingly quirky pattern?