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<TITLE>RE: [Haskell-cafe] Parsec Expected Type</TITLE>
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<P><FONT SIZE=2>Thanks, I'd thought it was something to do with incompatible types. I can now create a simpler problem:<BR>
<BR>
tester2 = reserved "parameter" <|> symbol ":"<BR>
<BR>
Certainly I could use reserved ":" instead of symbol, but where is my thinking with symbol here going wrong? Surely the above example isn't so odd?<BR>
<BR>
Paul<BR>
<BR>
<BR>
-----Original Message-----<BR>
From: Luke Palmer [<A HREF="mailto:lrpalmer@gmail.com">mailto:lrpalmer@gmail.com</A>]<BR>
Sent: Fri 3/28/2008 12:26 AM<BR>
To: Paul Keir<BR>
Cc: haskell-cafe@haskell.org<BR>
Subject: Re: [Haskell-cafe] Parsec Expected Type<BR>
<BR>
Hi Paul,<BR>
<BR>
2008/3/27 Paul Keir <pkeir@dcs.gla.ac.uk>:<BR>
> Hi,<BR>
><BR>
> Does anyone know why this reduced Parsec production stops compilation, and<BR>
> how I can fix it?<BR>
><BR>
> tester = reserved "parameter"<BR>
> <|> do { reserved "dimension"; symbol ":" }<BR>
<BR>
Look at the types of "reserved" and "symbol" (from<BR>
http://www.haskell.org/ghc/docs/latest/html/libraries/parsec/Text-ParserCombinators-Parsec-Token.html):<BR>
<BR>
symbol :: String -> CharParser st String<BR>
reserved :: String -> CharParser st ()<BR>
<BR>
The type of a do block is the same as the type of its last statement.<BR>
But (reserved "parameter") and (symbol ";") do not have the same type.<BR>
<BR>
Luke<BR>
<BR>
</FONT>
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