There is the property that once you &#39;move across the = to the right&#39;, the pattern matcher isn&#39;t allowed to backtrack and try other patterns any more, which might introduce some funny business. Though, I can&#39;t -- at the moment -- come up with a way that it would break anything.<div>
<div><div><div><br></div><div>-Edward Kmett<br><br><div class="gmail_quote">On Tue, Nov 17, 2009 at 2:20 PM, Doug McIlroy <span dir="ltr">&lt;<a href="mailto:doug@cs.dartmouth.edu">doug@cs.dartmouth.edu</a>&gt;</span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Is there a deep reason (beyond saving a sentence<br>
or two in the language definition) for requiring<br>
all patterns in a function binding to have the<br>
same explicit arity?<br>
<br>
For example, in<br>
        dropWhile0 :: Num a =&gt; [a] -&gt; [a]<br>
        dropWhile0 (0:xs) = dropWhile0 xs<br>
        dropWhile0 xs = xs<br>
why shouldn&#39;t the last line be replaceable by<br>
        dropWhile0 = id<br>
_______________________________________________<br>
Haskell-Cafe mailing list<br>
<a href="mailto:Haskell-Cafe@haskell.org">Haskell-Cafe@haskell.org</a><br>
<a href="http://www.haskell.org/mailman/listinfo/haskell-cafe" target="_blank">http://www.haskell.org/mailman/listinfo/haskell-cafe</a><br>
</blockquote></div><br></div></div></div></div>