Lazy List of Prime Numbers

Question

How would one implement a list of prime numbers in Haskell so that they could be retrieved lazily?

I am new to Haskell, and would like to learn about practical uses of t

Answer 1

primes = 2 : [x | x <- [3..], all (\y -> x `mod` y /= 0) 
                   (takeWhile (<= (floor . sqrt $ fromIntegral x)) primes)]

With 2 in the list initially, for each integer x greater than 2, check if for all y in primes such that y <= sqrt(x), x mod y != 0 holds, which means x has no other factors except 1 and itself.