On 15 October 2011 23:56, Bas van Dijk <[email protected]> wrote: > On 15 October 2011 23:17, Ertugrul Soeylemez <[email protected]> wrote: >> Both instances are valid here, and there is no mechanism to choose one of >> them. > > There is: OverlappingInstances[1] chooses the most specific instance. > So in case someVector :: Vector Word8 the instance Show (Vector Word8) > is chosen because it's the most specific.
This has the problem of incoherence in multi-module programs - GHC might chose different instances for the same type depending on compilation order. For a Show instance, this may be acceptable. _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
