Tuple-like constructors

Bulat Ziganshin bulatz at HotPOP.com
Thu Feb 9 04:48:11 EST 2006


Hello Simon,

Thursday, February 09, 2006, 11:19:00 AM, you wrote:

SPJ> |     deriving Bin for (,,,,,,,,,,,,,,,,,,,,)

SPJ> Yes -- a couple of times I've nearly gotten down to implementing this.

it is a real and well-known problem - that, for example, user of
library can't derive "Show" or "Eq" instance for datatypes defined in
this library. on the other side, usual "derivibg" clauses should be
able to use generic definitions, such as this for Binary class


-- 
Best regards,
 Bulat                            mailto:bulatz at HotPOP.com





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