There is reference in the paper that empty list indicates failure...so
could we just use it like Maybe? I'd like it very much if I could get
an example of a missed match by not using the complete match.
regards,
Kashyap
Sent from my Windows Phone
From: Roman Cheplyaka
Sent: 24/07/2013 8:19 PM
To: C K Kashyap
Cc: Haskell Cafe
Subject: Re: [Haskell-cafe] Parsec question
Think about this: if you always take only the first element, why do you
need lists at all?
Roman
* C K Kashyap
Dear Cafe,
I am trying to implement[1] parsec in go using the "Monadic Parser Combinators" paper [2] . I've been able to implement "plus" "bind" and "many" While doing the implementation - I looked at bind closely
bind :: Parser a -> (a -> Parser b) -> Parser b p `bind` f = \inp -> concat [f v inp' | (v,inp') <- p inp]
I wondered if the result needs the complete list - wouldn't just the first successful value suffice? Perhaps - p `bind` f = \inp -> take 1 $ concat [f v inp' | (v,inp') <- p inp]
Will this miss out matches?
Regards, Kashyap
[1] https://github.com/ckkashyap/parsec/blob/master/parsec.go [2] Monadic Parser Combinators: Graham Hutton, Erik Meijer
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