Parsec in 6.10 RC 1

Ian Lynagh igloo at
Sun Oct 12 11:24:03 EDT 2008

On Wed, Oct 08, 2008 at 05:10:53PM -0700, Greg Fitzgerald wrote:
> The instance for "Functor (Either ParserError)" disappeared.  Is that
> intentional?

The instance is still in Control.Monad.Instances.

The problem with the instance is that Haskell 98 doesn't say that it
exists, so we can't put it with either the Functor or Either
definitions. You were probably indirectly importing
Control.Monad.Instances before, but other changes now mean that you no
longer are.


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