[Haskell-cafe] How to update the RNG per call (State monad) when generating QuickCheck arbitraries?

Bryan O'Sullivan bos at serpentine.com
Tue Apr 26 18:39:45 CEST 2011

On Tue, Apr 26, 2011 at 9:16 AM, Daniel Kahlenberg
<d.kahlenberg at gmail.com>wrote:

> hold on I'd like to have the genArray call generating distinctive
> results in one IO execution

The problem you're seeing is due to the fact that you're not taking the
final RNG state from the first execution of your code and passing it as the
initial state to the second. Since you're initialising each one with the
same RNG state, you're getting the same results in each case.
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