Proposal: Add Text.Read.maybeRead :: Read a => String -> Maybe a
Twan van Laarhoven
twanvl at gmail.com
Fri Feb 8 15:35:34 EST 2008
David Menendez wrote:
>>Isn't the MonadPlus approach also by-default-safe?
>
> Safe, yes, but is it more useful?
Yes. In this case, take a parsing monad for example. You could write:
parseInt :: CharParser () Int
parseInt = do ds <- many digit
readM ds
And it would work automatically. A reading error would be propagated to the
parser monad, and it would backtrack/report the error/whatever.
Twan
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