Mimicking sets in JavaScript?

Question

I\'m working in JavaScript. I\'d like to store a list of unique, unordered string values, with the following properties:

1. a fast way to ask \'is A in t

Answer 1

I have started an implementation of Sets that currently works pretty well with numbers and strings. My main focus was the difference operation, so I tried to make it as efficient as I could. Forks and code reviews are welcome!

https://github.com/mcrisc/SetJS