<html><body><div>Fine in theory, but in practice when changes to the Prelude have been made previously, they have indeed affected the haskell98 and haskell2010 packages that have subsequently shipped with ghc.</div><div><br></div><div>See for instance:</div><div><br></div><div><a href="http://www.haskell.org/ghc/docs/7.6.2/html/users_guide/bugs-and-infelicities.html#haskell-standards-divergence">http://www.haskell.org/ghc/docs/7.6.2/html/users_guide/bugs-and-infelicities.html#haskell-standards-divergence</a></div><div><br></div><div><dt style="font-family: sans-serif; font-size: medium; "><span class="term">Num superclasses</span></dt><dd style="font-family: sans-serif; font-size: medium; "><p>The <code class="literal">Num</code> class does not have <code class="literal">Show</code> or <code class="literal">Eq</code> superclasses. You can make code that works with both Haskell98/Haskell2010 and GHC by: [workaround described]</p></dd></div><div><pre style="font-family: Helvetica,Arial,sans-serif; font-size: 13px; white-space: pre-wrap" data-mce-style="font-family: Helvetica,Arial,sans-serif; font-size: 13px; white-space: pre-wrap;"><dt style="font-family: sans-serif; font-size: medium; white-space: normal; "><span class="term">Bits superclasses</span></dt><dd style="font-family: sans-serif; font-size: medium; white-space: normal; "><p>The <code class="literal">Bits</code> class does not have a <code class="literal">Num</code> superclasses. It therefore does not have default methods for the <code class="literal">bit</code>, <code class="literal">testBit</code> and <code class="literal">popCount</code> methods.</p><p>You can make code that works with both Haskell2010 and GHC by: [workaround described]</p></dd></pre><pre style="font-family: Helvetica,Arial,sans-serif; font-size: 13px; white-space: pre-wrap" data-mce-style="font-family: Helvetica,Arial,sans-serif; font-size: 13px; white-space: pre-wrap;">Regards,
Malcolm</pre></div><div><br>On 23 May, 2013,at 09:23 AM, Edward Kmett <ekmett@gmail.com> wrote:<br><br></div><div><blockquote type="cite"><div class="msg-quote"><div dir="ltr">Note, the haskell98 and haskell2010 packages would be unaffected by this proposal as it stands.<div><br></div><div style="style" data-mce-style="">The (repeatedly raised in this thread) Applicative as a superclass of Monad situation on the other hand, sadly does impact them.</div><div style="style" data-mce-style=""><br></div><div style="style" data-mce-style="">-Edward</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Thu, May 23, 2013 at 4:19 AM, Henning Thielemann <span dir="ltr"><<a href="mailto:lemming@henning-thielemann.de" data-mce-href="mailto:lemming@henning-thielemann.de">lemming@henning-thielemann.de</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex" data-mce-style="margin: 0 0 0 .8ex; border-left: 1px #ccc solid; padding-left: 1ex;"><div class="im"><br> On Thu, 23 May 2013, Simon Peyton-Jones wrote:<br> <br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex" data-mce-style="margin: 0 0 0 .8ex; border-left: 1px #ccc solid; padding-left: 1ex;"> So there's a decision-making vacuum for the "GHC HQ" libraries. If that's the case, then the best thing is for GHC HQ to get out of the way!<br></blockquote><br></div>In the special case of adding Traversable and Foldable to Prelude, it worries me that it is about changing Prelude. I am more relaxed about changes to 'base'. However, since Prelude is part of the Haskell 98 and Haskell 2010 specification, I thought that changing Prelude could also be decided by the Haskell Prime committee.<div class="HOEnZb"><div class="h5"><br> <br> ______________________________<span data-mce-style="text-decoration: underline;" style="text-decoration: underline;"></span>_________________<br> Libraries mailing list<br> <a href="mailto:Libraries@haskell.org" data-mce-href="mailto:Libraries@haskell.org">Libraries@haskell.org</a><br> <a href="http://www.haskell.org/mailman/listinfo/libraries" data-mce-href="http://www.haskell.org/mailman/listinfo/libraries">http://www.haskell.org/<span data-mce-style="text-decoration: underline;" style="text-decoration: underline;"></span>mailman/listinfo/libraries</a><br></div></div></blockquote></div><br></div><div class="_stretch">_______________________________________________<br> Libraries mailing list<br> <a href="mailto:Libraries@haskell.org" data-mce-href="mailto:Libraries@haskell.org">Libraries@haskell.org</a><br> <a href="http://www.haskell.org/mailman/listinfo/libraries" data-mce-href="http://www.haskell.org/mailman/listinfo/libraries">http://www.haskell.org/mailman/listinfo/libraries</a><br></div></div></blockquote></div></body></html>