Re: [Haskell] A problem with overlapping instances and super-classes

On Mon, Jun 09, 2008 at 09:21:02AM +0100, Simon Peyton-Jones wrote:

This isn't great, but it's not really different than is the case for non-overlapping instances. Suppose module B1 declares 'instance C T', and uses that instance; and module B2 declares a *different* 'instance C T', and uses that instance; and Main imports B1 and B2, but does not use either instance directly. Then GHC will compile the program without complaint, although it is incoherent.

Isn't this a divergence from H98? Shouldn't we therefore list it on http://www.haskell.org/ghc/docs/latest/html/users_guide/bugs-and-infelicitie... ? Thanks Ian