'deriving Tree (Eq,Ord)'

John Meacham john at repetae.net
Tue Apr 4 16:02:16 EDT 2006

On Tue, Apr 04, 2006 at 01:13:32PM -0400, Robert Dockins wrote:
> The obvious solution is to allow out-of-defining-module deriving only  
> for data types where all constructors are exported.  Presumably, if  
> someone explicitly hid (at least some of) the constructors of a data  
> type, they did it for a reason and we can hope that they carefully  
> considered the external interface of that type (including instances).

indeed, that is actually a requirement of the original proposal.


John Meacham - ⑆repetae.net⑆john⑈

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