Sergio Pereira

I should have mentioned the version I'm running: 1.1.2 from July 16th, which seems to include the fixes from #80. Maybe it only fails for `window` then.

OK, I don't have a test but pasting this in a JS console seems to recreate the error: ``` javascript var father = {name: 'bob'} var child = {name: 'danny',...

I agree with @vkovalskiy. Throwing with a nice error message is better than trying to guess the best way to handle it.