urnie.js - A persistant random non-repeating picker Jack A Perkins, 2011 - released under GPLv2 Inspired by Max/MSP's [urn] object

Create a new Urn() and then call urn.grab(['some','array','here']) to be given a random member of the array. Urn removes the item from an internal list so that future calls to grab will not pick it again until all other items have been grabbed and the urn has been refreshed.

Urn is keyed with the value of the array that is passed in, an urn can therefor manage memebers for any number of unique arrays. Remember that urn keeps a reference of the array as a key, so you must call remove(key) if you wish to allow garbage collection to clean up.

!! Use urns on STATIC arrays or take Great caution !! Changing the members in your array inbetween calls to grab will produce different results than you may be expecting as JS treats each array as a different key. Check out the demo.html for an example.

Urn currently doesn't have a feature to prevent repeating elements between the last and first calls of seperate replenishments.