Hello Anatoly,<br><br><div class="gmail_quote">On Sat, Apr 11, 2009 at 20:44, Anatoly Yakovenko <span dir="ltr"><<a href="mailto:aeyakovenko@gmail.com">aeyakovenko@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
i am trying to understand how data.data works. How would i traverse<br>
the subterms of one type and build another type out of them.<br>
something like this:<br>
<br>
> gmapQ (\a -> Right a) (Just "hello")</blockquote><div><br>I am not sure I understand what you're trying to do here. However, in general, 'gmapQ' is used in combination with 'mkQ' or 'extQ'. Those are not in Data.Data: you can import Data.Generics to get everything syb-related.<br>
<br><br>Cheers,<br>Pedro<br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><br>
<br>
<interactive>:1:0:<br>
Inferred type is less polymorphic than expected<br>
Quantified type variable `d' escapes<br>
In the first argument of `gmapQ', namely `(\ a -> Right a)'<br>
In the expression: gmapQ (\ a -> Right a) (Just "hello")<br>
In the definition of `it':<br>
it = gmapQ (\ a -> Right a) (Just "hello")<br>
<br>
<br>
Thanks,<br>
Anatoly<br>
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