Hi Robert,
Is it possible to generate random numbers that are "unique" in O(1) in Haskell?
I mean something like the GUID-thingy Windows uses.
Of course, I could create unique numbers by incrementing a global value, but for security reasons I need random numbers. Also, I could use a list of numbers already in use, but this would mean that I'd not be able to generate a new number in O(1).
do you really need random numbers? If not: I vaguely remember an algorithm from one of the "Graphic Gems" books, implementing some sort of fancy counter which goes through all numbers from 0,...,2^n-1 in a seemingly random, but of course deterministic and repeatable order. It was used for some sort of cross dissolve effect, because you can index every pixel of a bitmap with one number (ignoring numbers mapped to positions outside the screen/viewport/whatever) and this way blend from one image to another. If this sort of behavious suits your needs just let me know and I will look it up. Regards, Jens