Differences in pattern matching syntax?

[Brandon S. Allbery KF8NH]

On 2009 Jan 16, at 11:23, Bulat Ziganshin wrote:
> Friday, January 16, 2009, 7:07:09 PM, you wrote:
>>   instance Eq RuleType
>
> this is very common error. it would be great to find some way to deal
> with it (for predefined classes at very least...)



It wouldn't catch everything, but might it make sense to output a  
warning on empty instance declarations?

-- 
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH