Control.Monad.State found in multiple packages haskell

Question

While evaluating the line \"import Control.Monad.State\" in a Haskell module, GHC gives me the following error:

Could not find module `Control.Monad         


        

Answer 1

Both packages implement Control.Monad.State and GHC does not know which implementation it should prefer, so you need to hide one of the packages from GHC. Seems like the -ignore-package GHC flag might help you here.