But isn't the point of this code that you don't need that type signature? If I knew in advance that it was an Integer then I wouldn't need to passs "Integer" in the list.
-Alex- On Thu, 29 Apr 2004, Chung-chieh Shan wrote: > On 2004-04-28T23:33:31-0400, S. Alexander Jacobson wrote: > > I don't think this works. I just tried it with: > > main = print $ lookupRead 1 [(1,("Integer","100"))] > > This fails for the same reason > > print $ read "100" > > fails. You need to give a type signature to avoid type-class instance > ambiguity: > > main = print $ (lookupRead 1 [(1,("Integer","100"))] :: Maybe Integer) > > On GHCi 6.2.1, the above yields "Just 100" for me. > > -- > Edit this signature at http://www.digitas.harvard.edu/cgi-bin/ken/sig > Be it declared and enacted by this present Parliament / That the People > of England / are / a Commonwealth and free State / without any King or > House of Lords. -- An Act declaring England to be a Commonwealth > 1649-05-19 | 355 years | 2004-05-19 http://tinyurl.com/2dqnh > _________________________________________________________________ S. Alexander Jacobson mailto:[EMAIL PROTECTED] tel:917-770-6565 http://alexjacobson.com _______________________________________________ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe