On Thu, 2011-12-29 at 21:04 +0000, Steve Horne wrote:
AFAIK there's no hidden unsafePerformIO sneaking any entropy in behind the scenes. Even if there was, it might be a legitimate reason for unsafePerformIO - random numbers are in principle non-deterministic, not determined by the current state of the outside world and which-you-evaluate-first should be irrelevant.
This is certainly not legitimate. Anything that can't be memoized has no business advertising itself as a function in Haskell. This matters quite a lot... programs might change from working to broken due to something as trivial as inlining by the compiler (see the ugly NOINLINE annotations often used with unsafePerformIO tricks for initialization code for an example). -- Chris Smith