Proposal: Add Text.Read.maybeRead :: Read a => String -> Maybe a
dave at zednenem.com
Fri Feb 8 00:17:31 EST 2008
On Feb 7, 2008 6:12 PM, Ross Paterson <ross at soi.city.ac.uk> wrote:
> I think this is a good idea, though I normally write the equivalent of
> maybeRead :: Read a => String -> Maybe a
> maybeRead s = case reads s of
> [(x, rest)] | all isSpace rest -> Just x
> _ -> Nothing
> and would prefer not to generalize it to any monad. fail is a wart,
> not a design pattern.
I also prefer Maybe to fail. Error strings are only useful if you're
ignoring them or passing them to the user without interpretation.
Dave Menendez <dave at zednenem.com>
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