many1 no longer works with Parsec 3.x

Posted by Zak on Stack Overflow See other posts from Stack Overflow or by Zak
Published on 2010-03-30T14:20:46Z Indexed on 2010/03/30 14:23 UTC
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parsec

After updating to Parsec 3.1 from 2.x, code using many1, such as word = many1 letter fails with

No instance for (Stream s m Char) arising from a use of `letter'

I found a mailing list post claiming that adding {-#LANGUAGE NoMonomorphismRestriction #-} to the top of the source file would solve the problem, but it did not.

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