[Haskell-cafe] Parser problem continued

[Nicola Whitehead]

Curiouser and curiouser...
 
expr :: Parser Int
expr = do t <- term
          do symbol "+"
             e <- expr
          return (t + e)
       +++ return t

solves the undefined variable problem but introduces a new 'Last operator in do {...} must be an expression' error, which then disappears if I explicitly return e
 
expr :: Parser Int
expr = do t <- term
          do symbol "+"
             e <- expr
             return e
          return (t + e)
       +++ return t

to give me the original undefined variable t error at the line expr = do t <- term . It looks in scope to me... :(
 
Thanks,
 
Nik
 
Dr Nik Freydís Whitehead
University of Akureyri, Iceland
*********************************************************************
Having the moral high ground is good.
Having the moral high ground and an FGMP-15 is better.
*********************************************************************
 
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