decouple the builder classes from the model. Builder objects should be easier to reuse now.
… the Association and its inherited classes
Method compilation provides better performance and I think the code comes out cleaner as well. A knock on effect is that methods that get redefined produce warnings. I think this is a good thing. I had to deal with a bunch of warnings coming from our tests, though.
It's not really a good idea to have this as a global config option. We should allow people to specify the behaviour per association. There will now be two new values: * :dependent => :restrict_with_exception implements the current behaviour of :restrict. :restrict itself is deprecated in favour of :restrict_with_exception. * :dependent => :restrict_with_error implements the new behaviour - it adds an error to the owner if there are dependent records present See #4727 for the original discussion of this.