{-# LANGUAGE PackageImports #-} {-# LANGUAGE CPP #-} module Data.Either ( module Export, #if MIN_VERSION_base(4,7,0) #else isRight, isLeft, #endif ) where import "base" Data.Either as Export #if MIN_VERSION_base(4,7,0) #else isRight :: Either a b -> Bool isRight (Right _) = True isRight _ = False isLeft :: Either a b -> Bool isLeft = not . isRight #endif