Proposal: Move the instances from Control.Monad.Instances into GHC.Base

Yitzchak Gale gale at
Sun Nov 13 12:21:12 CET 2011

Edward Kmett wrote:
> I propose that we move the contents of Control.Monad.Instances
> into GHC.Base...
> ...and make
> Control.Monad.Instances an empty stub that exists just to avoid breaking
> code, and which can be used to support any other missing instances for
> Prelude types in the future...


This implies that your proposal also includes
removing the import of Control.Monad.Instances
from Control.Applicative. But you did not explicitly
say so. Is this correct?

If there is anywhere else in the base libraries where
Control.Monad.Instances is imported, presumably
that import should also be removed. Are we 100%
certain that no other such import exists?


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