[Haskell-cafe] Not in scope
jochem at functor.nl
Sat Apr 25 16:34:07 EDT 2009
siso dagbovie wrote:
> I've defined the datatype:
> data Graph a b = Empty | Context a b :& Graph a b
> and the function
> isEmpty :: Graph a b -> Bool
> isEmpty Empty = True
> isEmpty _ = False
> and when I do a test run with the graph,
> ( [ ],2,'c',[("down",3)]) :& Empty
> Haskell is bringing the message " Not in scope: data constructor `:&' "
> Why is that so?
This works for me. Are the definitions in the same file? Otherwise, you
will need to import your definition.
All the best,
Jochem Berndsen | jochem at functor.nl
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