How to generate a list of all possible strings from shortest to longest

Question

I need to generate an infinite list of strings using numbers and letters. The first string should simply be \"a\", then \"b\" through to \"z\", then \"0\" through to \"9\", the

Answer 1

This can be done simply by a predefined function replicateM from (Control.Monad).

string = concatMap (\n -> replicateM n (['a'..'z']++['0'..'9'])) [1..]