Hi,

I've started to learn F# and find myself firmly set in a Haskell frame of mind in all things funtional. I'd like some advice in the F#-ish way of thinking, examplified this sample of naive prime testing:

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let isPrime n = 
    match n with
    | n when n <= 1 -> false
    | 2 -> true
    | _ -> let top = int (sqrt (float n)) 
           [ for x in 2..top when (n % x) = 0 -> x ] = []

That would be the Haskell way of doing it, because you always think in terms of lists. Haskell would only evaluate the above list comprehension until the condition became false, so the example is an acceptable Haskell solution. For example, "isPrime 12345678" would only generate the list [2] and then terminate, returning false.

When lists are completely evaluated, you obliously can't be so generous with them. How could an example like this be done the F# way?