can we just get this straight please!
you do not need any prior programming knowledge before entering as a fresher into computing.
i had none and I learnt haskell, prolog, kenya, java etc.. totally fine.
its a bit of hard work at the start trying to understand haskell but with a bit of work its fine.
there is really no need to study it in advance as the first few weeks guide you through it all and hopefully you'll have Tony Field in lectures so you'll be sorted!
you're just wasting your time trying to understand it now, if you're really anxious to study work on some further maths, pick up the p4, p5 and p6 books and study that stuff