"Simon Marlow" writes:

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One reason, I think, is lazy I/O(*). It's to stop you accidentally

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(*) kill it! die! die!

So you want main = readFile "/dev/zero" >> return () to terminate violantly rather than terminate peacefully? :)

Seriously, I understand that the IO monad is the most intuitive and robust when it is strict. But sometimes it is also nice if one could map a file to a lazy string.

It is nice, but it introduces too many problems. What happens to any I/O errors encountered by the lazy I/O? They have to be discarded, which means you can't effectively use lazy I/O for robust applications anyway. Cheers, Simon