Hi Jan,<br><br><div class="gmail_quote">On Wed, Sep 15, 2010 at 10:30, Jan Christiansen <span dir="ltr">&lt;<a href="mailto:jac@informatik.uni-kiel.de">jac@informatik.uni-kiel.de</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">

Hi,<br>
<br>
I want to define a function which is generic for all unary type constructors using the regular package. More precisely, I want to define a function like the following, which replaces every polymorphic component by the position of the component in the generic representation.<br>


<br>
  shape :: (Regular f, Shape (PF f)) =&gt; f a -&gt; f [Bool]<br></blockquote><div><br>I&#39;m not sure I fully understand what you&#39;re trying to do. Could you provide typical use cases of your function, to several arguments of different types?<br>

<br><br>Cheers,<br>Pedro<br> </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<br>
Is it correct that it is not possible to implement a function like this using regular? Or do I miss something?<br>
<br>
I have implemented the function by using different representation types K, I and so forth that take an additional argument. Furthermore I have added an additional type to mark the polymorphic component.<br>
<br>
Thanks, Jan<br>
_______________________________________________<br>
Generics mailing list<br>
<a href="mailto:Generics@haskell.org" target="_blank">Generics@haskell.org</a><br>
<a href="http://www.haskell.org/mailman/listinfo/generics" target="_blank">http://www.haskell.org/mailman/listinfo/generics</a><br>
</blockquote></div><br>