[Haskell-beginners] GHCi won't allow type declaration as shown in LYAHFGG

Keshav Kini keshav.kini at gmail.com
Thu May 31 23:16:04 CEST 2012


Stan Kulp <stan_kulp at yahoo.com> writes:
> I have been working my way through "Learn You a Haskell for Greater Good" and
> am stumped when I get to the "Syntax in Functions - Pattern Matching" section.
>
> The book shows the following expression...
>
> ghci> lucky :: (Integral a) => a -> String  

As far as I can see, the live version of `the section you mention`_ on
learnyouahaskell.com does not contain this text - it doesn't have the
"ghci> " at the beginning of the line. Besides what others have said in
response to your question, I would add that you should make sure to read
LYAH on the website if possible - other sources might be out of date, as
I think the author does update the website version from time to time.

.. _the section you mention:
   http://learnyouahaskell.com/syntax-in-functions#pattern-matching

-Keshav




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