I would create codepen to test js libs there, it should operate on strings not numbers.. mathjs doesnt have online calculator probably it's not the best tool around
— Hmmh
— Https://github.com/peterolson/BigInteger.js
— Well, he needs floats though
— ^
— Okay, how would you get the name using eval?
— I'll bite
— Write your own custom JS runtime over JS
— It exists
— That provides builtin methods to get variable names during runtime