Fix up the instance-declaration re-engineering story
authorsimonpj@microsoft.com <unknown>
Fri, 5 Sep 2008 17:26:54 +0000 (17:26 +0000)
committersimonpj@microsoft.com <unknown>
Fri, 5 Sep 2008 17:26:54 +0000 (17:26 +0000)
commit4f597914955e1eeb08243f8b0743387703fc62b6
tree74253f17877841985ad63b8625af7eb8329b13a5
parent85cdcb79e30fc86ca8b5dfcc2d4a77cadd4990bd
Fix up the instance-declaration re-engineering story

This patch deals with a rather complicated situation involving
overlapping instances.  It's all explained in the commments
   Note [Subtle interaction of recursion and overlap]

The absence of this case make DoCon and regex-base fail with
an error about overlapping instances.  Now they work properly
again.
compiler/typecheck/TcInstDcls.lhs