This provides an `Either` monad transformer that unlike `ErrorT` is unencumbered by a constraint on its `Left` hand argument. ok sthen@ (will be hooked to the build during the ghc update)
This provides an `Either` monad transformer that unlike `ErrorT` is unencumbered by a constraint on its `Left` hand argument. ok sthen@ (will be hooked to the build during the ghc update)