Well, I don't like these exception oriented programming, they used to be slow, and low legible. I agree that in this case the other way is pretty more legible, but I don't know about what is faster here, let `to_sym` raise exception, or test `respond_to?`.

I just changed it because I'd changed some methods of this source file before. I forgot this file in the simplification, the `String` method that I added is no longer necessary. I'll remove it and take a look at the docs.

If you want, I keep the code as before, just adding the docs.