Hello!
I have a program that is using ST.Strict, which works fine.
However, the program needs to be extended, and to do that,
lazy evaluation is needed. As a result of that, I have switched
to ST.Lazy to be able to do stuff like

foo y = do
x <- something
xs <- foo (y+1)
return (x:xs)

As Ryan points out, this will not do what you want. But that is incidental, not essential:

foo y = do
x <- something
fmap (x:) $ foo (y+1)

Luke