I think you should think ahead and change it to "any-pad" or something similar and offer adapters/plugins. What are users of your library do when some industry-disrupting startup comes in offering left- and mid- pads?

Changing your npm shouldn't be a problem, just unpublish it and create new one.

Also don't forget to check trademark list before creating npm because "they will come knocking on your doors closing all your accounts".

The try in browser fails with an unexpected token syntax error. Do you accept PRs?

yeah, I added some tests...did you mean to return strings? Also fixed some syntax errors