[Haskell-cafe] Question about IO, interact functions,

[David Leimbach]

main = interact (unlines . lines)
This *appears* to somewhat reliably get me functionality that looks like
take a line of input, and print it out.

Is this behavior something I can rely on working?

I like the idea that lines can pull lines lazily from "getContents" which
lazily consume the input.  But I'm concerned that relying on a pure function
like "unlines . lines" to sequence IO is a bit too implicit in nature.

I really like the idea of doing things through functions like Interact in
that they appear to allow me to keep most of my code pure, but if I can't
get the IO sequencing I want to be guaranteed to work, I suppose I'll have
to dive back into "imperative IO" land that I get from the IO Monad.

Should I feel guilty for doing so?  :-)

Dave
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