First things first: >>> When you click on Element, you'll see no mention >>> of each or to_a, or any mention of a class that might >>> have defined them. There is no comment on node_type, >>> and no pointers to code, in lieu of commentary. This is related to this: >>> But it bugs me that that it doesn't even name >>> superclasses. (It /seems/ to name modules, but >>> I have no way of knowing if it's complete.) Which isn't actually the case. If you look at the blue title bar, you see this: Class: REXML::Element In: temp/element.rb Parent: Parent 'Parent' is the superclass. If you click on that, you can see that the Parent class includes Enumerable (which would account for a default each method that you seem to be looking for). You can find the entire source in 'temp/element.rb', which is a pointer to code, and you can get the source for a method by clicking on its signature (you get a pop-up). Reading API docs is a pain, I know, but it does help to know how they work. Hope this helps a bit. matthew smillie.