[Haskell] IO, exceptions and error handling
timothy.docker at macquarie.com
Mon Jun 14 12:30:54 EDT 2004
Philippa Cowderoy wrote:
> The ability to fail doesn't need the do notation, just use of
> return for success - similar for propagating failure.
I'm not sure I understand. Do you mean writing functions
sqr x | x < 0 = fail "less than zero"
| otherwise = return (sqrt x)
If so, I don't see how I can use this without either do
test x = do
v1 <- sqr x
v2 <- sqr (x+1)
I can't (easily) write
text c = sqr x + sqr (x+1)
which was what I was getting at.
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