{-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE CPP #-} -- | BasicPrelude mostly re-exports -- several key libraries in their entirety. -- The exception is Data.List, -- where various functions are replaced -- by similar versions that are either -- generalized, operate on Text, -- or are implemented strictly. module BasicPrelude ( -- * Module exports module CorePrelude , module Data.List , module Control.Monad -- ** Folds and traversals , Foldable ( foldMap , foldr , foldr' , foldl , foldl' , foldr1 , foldl1 ) -- In base-4.8, these are instance methods. , elem , maximum , minimum , traverse_ , sequenceA_ , for_ , maximumBy , minimumBy , Traversable ( traverse , sequenceA , mapM , sequence ) , for -- * Enhanced exports -- ** Simpler name for a typeclassed operation , map , empty , (++) , concat , intercalate -- ** Strict implementation , BasicPrelude.sum , BasicPrelude.product -- ** Text for Read and Show operations , tshow , fromShow , read , readIO -- ** FilePath for file operations , readFile , writeFile , appendFile -- * Text exports -- ** Text operations (Pure) , Text.lines , Text.words , Text.unlines , Text.unwords , textToString , ltextToString , fpToText , fpFromText , fpToString , encodeUtf8 , decodeUtf8 -- ** Text operations (IO) , getLine , getContents , interact -- * Miscellaneous prelude re-exports -- ** Math , Prelude.gcd , Prelude.lcm -- ** Show and Read , Prelude.Show (..) , Prelude.ShowS , Prelude.shows , Prelude.showChar , Prelude.showString , Prelude.showParen , Prelude.ReadS , Prelude.readsPrec , Prelude.readList , Prelude.reads , Prelude.readParen , Prelude.lex , readMay -- ** IO operations , getChar , putChar , readLn ) where import CorePrelude import Data.List hiding ( -- prefer monoid versions instead (++) , concat , intercalate -- prefer Text versions instead , lines , words , unlines , unwords -- prefer map = fmap instead , map -- prefer strict versions , sum , product -- prefer Foldable versions , elem , foldl , foldl' , foldl1 , foldr , foldr1 , maximum , minimum , maximumBy , minimumBy ) -- Import *all of the things* from Control.Monad, -- specifically, the list-based things that -- CorePrelude doesn't export import Control.Monad hiding ( -- Also exported by Data.Traversable. mapM , sequence ) import Data.Foldable (Foldable(..), elem, maximum, minimum, traverse_, sequenceA_, for_) import Data.Traversable (Traversable(..), for) import qualified Data.Text as Text import qualified Data.Text.IO as Text import qualified Data.Text.Lazy as LText import qualified Data.Text.Lazy.IO as LText import qualified Prelude import Data.Text.Encoding (encodeUtf8, decodeUtf8With) import Data.Text.Encoding.Error (lenientDecode) import qualified Text.Read #if MIN_VERSION_base(4,10,0) import Data.Foldable (maximumBy, minimumBy) #else maximumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a maximumBy cmp = foldl1 max' where max' x y = case cmp x y of GT -> x _ -> y minimumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a minimumBy cmp = foldl1 min' where min' x y = case cmp x y of GT -> y _ -> x #endif -- | > map = fmap map :: (Functor f) => (a -> b) -> f a -> f b map = fmap -- | > empty = mempty empty :: Monoid w => w empty = mempty {-# DEPRECATED empty "Use mempty" #-} infixr 5 ++ -- | > (++) = mappend (++) :: Monoid w => w -> w -> w (++) = mappend -- | > concat = mconcat concat :: Monoid w => [w] -> w concat = mconcat -- | > intercalate = mconcat .: intersperse intercalate :: Monoid w => w -> [w] -> w intercalate xs xss = mconcat (Data.List.intersperse xs xss) -- | Compute the sum of a finite list of numbers. sum :: (Foldable f, Num a) => f a -> a sum = Data.Foldable.foldl' (+) 0 -- | Compute the product of a finite list of numbers. product :: (Foldable f, Num a) => f a -> a product = Data.Foldable.foldl' (*) 1 -- | Convert a value to readable Text -- -- @since 0.6.0 tshow :: Show a => a -> Text tshow = Text.pack . Prelude.show -- | Convert a value to readable IsString -- -- Since 0.3.12 fromShow :: (Show a, IsString b) => a -> b fromShow = fromString . Prelude.show -- | Parse Text to a value read :: Read a => Text -> a read = Prelude.read . Text.unpack -- | The readIO function is similar to read -- except that it signals parse failure to the IO monad -- instead of terminating the program. -- -- @since 0.7.0 readIO :: (MonadIO m, Read a) => Text -> m a readIO = liftIO . Prelude.readIO . Text.unpack -- | Read a file and return the contents of the file as Text. -- The entire file is read strictly. -- -- @since 0.7.0 readFile :: MonadIO m => FilePath -> m Text readFile = liftIO . Text.readFile -- | Write Text to a file. -- The file is truncated to zero length before writing begins. -- -- @since 0.7.0 writeFile :: MonadIO m => FilePath -> Text -> m () writeFile p = liftIO . Text.writeFile p -- | Write Text to the end of a file. -- -- @since 0.7.0 appendFile :: MonadIO m => FilePath -> Text -> m () appendFile p = liftIO . Text.appendFile p textToString :: Text -> Prelude.String textToString = Text.unpack ltextToString :: LText -> Prelude.String ltextToString = LText.unpack -- | This function assumes file paths are encoded in UTF8. If it -- cannot decode the 'FilePath', the result is just an approximation. -- -- Since 0.3.13 fpToText :: FilePath -> Text fpToText = Text.pack {-# DEPRECATED fpToText "Use Data.Text.pack" #-} -- | -- Since 0.3.13 fpFromText :: Text -> FilePath fpFromText = Text.unpack {-# DEPRECATED fpFromText "Use Data.Text.unpack" #-} -- | -- Since 0.3.13 fpToString :: FilePath -> Prelude.String fpToString = id {-# DEPRECATED fpToString "Use id" #-} -- | Note that this is /not/ the standard @Data.Text.Encoding.decodeUtf8@. That -- function will throw impure exceptions on any decoding errors. This function -- instead uses @decodeLenient@. decodeUtf8 :: ByteString -> Text decodeUtf8 = decodeUtf8With lenientDecode -- | -- @since 0.7.0 getLine :: MonadIO m => m Text getLine = liftIO Text.getLine -- | -- @since 0.7.0 getContents :: MonadIO m => m LText getContents = liftIO LText.getContents -- | -- @since 0.7.0 interact :: MonadIO m => (LText -> LText) -> m () interact = liftIO . LText.interact readMay :: Read a => Text -> Maybe a readMay = Text.Read.readMaybe . Text.unpack -- | -- @since 0.7.0 getChar :: MonadIO m => m Char getChar = liftIO Prelude.getChar -- | -- @since 0.7.0 putChar :: MonadIO m => Char -> m () putChar = liftIO . Prelude.putChar -- | The 'readLn' function combines 'getLine' and 'readIO'. -- -- @since 0.7.0 readLn :: (MonadIO m, Read a) => m a readLn = liftIO Prelude.readLn