-{-# LANGUAGE RankNTypes, TypeFamilies, BangPatterns #-}
+{-# LANGUAGE RankNTypes, TypeFamilies, BangPatterns, CPP #-}
#if __GLASGOW_HASKELL__ >= 702
{-# LANGUAGE Trustworthy #-}
#endif
module Pipes.Text (
-- * Producers
- fromLazy,
- stdin,
- fromHandle,
- readFile,
- stdinLn,
+ fromLazy
+ , stdin
+ , fromHandle
+ , readFile
-- * Consumers
- stdout,
- stdoutLn,
- toHandle,
- writeFile,
+ , stdout
+ , toHandle
+ , writeFile
-- * Pipes
- map,
- concatMap,
- take,
- drop,
- takeWhile,
- dropWhile,
- filter,
- scan,
- encodeUtf8,
- pack,
- unpack,
- toCaseFold,
- toLower,
- toUpper,
- stripStart,
+ , map
+ , concatMap
+ , take
+ , drop
+ , takeWhile
+ , dropWhile
+ , filter
+ , scan
+ , encodeUtf8
+ , pack
+ , unpack
+ , toCaseFold
+ , toLower
+ , toUpper
+ , stripStart
-- * Folds
- toLazy,
- toLazyM,
- foldChars,
- head,
- last,
- null,
- length,
- any,
- all,
- maximum,
- minimum,
- find,
- index,
- count,
+ , toLazy
+ , toLazyM
+ , foldChars
+ , head
+ , last
+ , null
+ , length
+ , any
+ , all
+ , maximum
+ , minimum
+ , find
+ , index
+ , count
+
+ -- * Primitive Character Parsers
+ -- $parse
+ , nextChar
+ , drawChar
+ , unDrawChar
+ , peekChar
+ , isEndOfChars
+
+ -- * Parsing Lenses
+ , splitAt
+ , span
+ , break
+ , groupBy
+ , group
+ , word
+ , line
+
+ -- * Decoding Lenses
+ , decodeUtf8
+ , codec
+
+ -- * Codecs
+ , utf8
+ , utf16_le
+ , utf16_be
+ , utf32_le
+ , utf32_be
+
+ -- * Other Decoding/Encoding Functions
+ , decodeIso8859_1
+ , decodeAscii
+ , encodeIso8859_1
+ , encodeAscii
+
+ -- * FreeT Splitters
+ , chunksOf
+ , splitsWith
+ , splits
+-- , groupsBy
+-- , groups
+ , lines
+ , words
- -- * Splitters
- splitAt,
- chunksOf,
- span,
- break,
- splitWith,
- split,
- groupBy,
- group,
- lines,
- words,
- decodeUtf8,
- decode,
-- * Transformations
- intersperse,
+ , intersperse
+ , packChars
-- * Joiners
- intercalate,
- unlines,
- unwords,
-
- -- * Character Parsers
- -- $parse
- nextChar,
- drawChar,
- unDrawChar,
- peekChar,
- isEndOfChars,
+ , intercalate
+ , unlines
+ , unwords
- -- * Re-exports
+ -- * Re-exports
-- $reexports
- module Data.Text,
- module Pipes.Parse
+ , module Data.ByteString
+ , module Data.Text
+ , module Data.Profunctor
+ , module Data.Word
+ , module Pipes.Parse
+ , module Pipes.Group
+ , module Pipes.Text.Internal
) where
import Control.Exception (throwIO, try)
+import Control.Applicative ((<*))
import Control.Monad (liftM, unless, join)
-import Control.Monad.Trans.State.Strict (StateT(..))
+import Control.Monad.Trans.State.Strict (StateT(..), modify)
import Data.Monoid ((<>))
import qualified Data.Text as T
import qualified Data.Text.IO as T
import Data.ByteString.Unsafe (unsafeTake, unsafeDrop)
import Data.ByteString (ByteString)
import qualified Data.ByteString as B
+import qualified Data.ByteString.Char8 as B8
import Data.Char (ord, isSpace)
+import Data.Functor.Constant (Constant(Constant, getConstant))
import Data.Functor.Identity (Identity)
+import Data.Profunctor (Profunctor)
+import qualified Data.Profunctor
import qualified Data.List as List
import Foreign.C.Error (Errno(Errno), ePIPE)
import qualified GHC.IO.Exception as G
import Pipes
import qualified Pipes.ByteString as PB
-import qualified Pipes.ByteString as PBP
-import qualified Pipes.Text.Internal as PE
-import Pipes.Text.Internal (Codec(..))
-import Pipes.Text.Parse (
- nextChar, drawChar, unDrawChar, peekChar, isEndOfChars )
+import qualified Pipes.Text.Internal as PI
+import Pipes.Text.Internal
import Pipes.Core (respond, Server')
+import Pipes.Group (concats, intercalates, FreeT(..), FreeF(..))
+import qualified Pipes.Group as PG
import qualified Pipes.Parse as PP
-import Pipes.Parse ( FreeT)
+import Pipes.Parse (Parser)
import qualified Pipes.Safe.Prelude as Safe
import qualified Pipes.Safe as Safe
import Pipes.Safe (MonadSafe(..), Base(..))
import qualified System.IO as IO
import Data.Char (isSpace)
import Data.Word (Word8)
+
import Prelude hiding (
all,
any,
fromHandle :: MonadIO m => IO.Handle -> Producer Text m ()
fromHandle h = go where
go = do txt <- liftIO (T.hGetChunk h)
- unless (T.null txt) $ do yield txt
- go
+ unless (T.null txt) ( do yield txt
+ go )
{-# INLINABLE fromHandle#-}
readFile file = Safe.withFile file IO.ReadMode fromHandle
{-# INLINE readFile #-}
-{-| Stream lines of text from stdin (for testing in ghci etc.)
-
->>> let safely = runSafeT . runEffect
->>> safely $ for Text.stdinLn (lift . lift . print . T.length)
-hello
-5
-world
-5
-
--}
-stdinLn :: MonadIO m => Producer' Text m ()
-stdinLn = go where
- go = do
- eof <- liftIO (IO.hIsEOF IO.stdin)
- unless eof $ do
- txt <- liftIO (T.hGetLine IO.stdin)
- yield txt
- go
-{-# INLINABLE stdinLn #-}
{-| Stream text to 'stdout'
Unlike 'toHandle', 'stdout' gracefully terminates on a broken output pipe.
- Note: For best performance, use @(for source (liftIO . putStr))@ instead of
- @(source >-> stdout)@ in suitable cases.
+ Note: For best performance, it might be best just to use @(for source (liftIO . putStr))@
+ instead of @(source >-> stdout)@ .
-}
stdout :: MonadIO m => Consumer' Text m ()
stdout = go
Right () -> go
{-# INLINABLE stdout #-}
-stdoutLn :: (MonadIO m) => Consumer' Text m ()
-stdoutLn = go
- where
- go = do
- str <- await
- x <- liftIO $ try (T.putStrLn str)
- case x of
- Left (G.IOError { G.ioe_type = G.ResourceVanished
- , G.ioe_errno = Just ioe })
- | Errno ioe == ePIPE
- -> return ()
- Left e -> liftIO (throwIO e)
- Right () -> go
-{-# INLINABLE stdoutLn #-}
{-| Convert a text stream into a 'Handle'
writeFile file = Safe.withFile file IO.WriteMode toHandle
{-# INLINE writeFile #-}
+
+type Lens' a b = forall f . Functor f => (b -> f b) -> (a -> f a)
+
+type Iso' a b = forall f p . (Functor f, Profunctor p) => p b (f b) -> p a (f a)
+
+(^.) :: a -> ((b -> Constant b b) -> (a -> Constant b a)) -> b
+a ^. lens = getConstant (lens Constant a)
+
+
-- | Apply a transformation to each 'Char' in the stream
map :: (Monad m) => (Char -> Char) -> Pipe Text Text m r
map f = P.map (T.map f)
p >-> unpack = for p (\txt -> yield (T.unpack txt))
#-}
--- | @toCaseFold@, @toLower@, @toUpper@ and @stripStart@ are standard 'Text' utility,
--- here acting on a 'Text' pipe, rather as they would on a lazy text
+-- | @toCaseFold@, @toLower@, @toUpper@ and @stripStart@ are standard 'Text' utilities,
+-- here acting as 'Text' pipes, rather as they would on a lazy text
toCaseFold :: Monad m => Pipe Text Text m ()
toCaseFold = P.map T.toCaseFold
{-# INLINEABLE toCaseFold #-}
let text = T.stripStart chunk
if T.null text
then stripStart
- else cat
+ else do yield text
+ cat
{-# INLINEABLE stripStart #-}
-- | @(take n)@ only allows @n@ individual characters to pass;
:: Monad m
=> (x -> Char -> x) -> x -> (x -> r) -> Producer Text m () -> m r
foldChars step begin done = P.fold (T.foldl' step) begin done
-{-# INLINABLE fold #-}
+{-# INLINABLE foldChars #-}
-- | Retrieve the first 'Char'
head :: (Monad m) => Producer Text m () -> m (Maybe Char)
Just c -> Just (min c (T.minimum txt))
{-# INLINABLE minimum #-}
+
-- | Find the first element in the stream that matches the predicate
find
:: (Monad m)
count c p = P.fold (+) 0 id (p >-> P.map (fromIntegral . T.count c))
{-# INLINABLE count #-}
--- | Transform a Pipe of 'ByteString's expected to be UTF-8 encoded into a Pipe of Text
--- returning a Pipe of ByteStrings that begins at the point of failure.
-decodeUtf8 :: Monad m => Producer ByteString m r -> Producer Text m (Producer ByteString m r)
-decodeUtf8 = go B.empty PE.streamDecodeUtf8 where
+{-| Consume the first character from a stream of 'Text'
+
+ 'next' either fails with a 'Left' if the 'Producer' has no more characters or
+ succeeds with a 'Right' providing the next character and the remainder of the
+ 'Producer'.
+-}
+nextChar
+ :: (Monad m)
+ => Producer Text m r
+ -> m (Either r (Char, Producer Text m r))
+nextChar = go
+ where
+ go p = do
+ x <- next p
+ case x of
+ Left r -> return (Left r)
+ Right (txt, p') -> case (T.uncons txt) of
+ Nothing -> go p'
+ Just (c, txt') -> return (Right (c, yield txt' >> p'))
+{-# INLINABLE nextChar #-}
+
+{-| Draw one 'Char' from a stream of 'Text', returning 'Left' if the
+ 'Producer' is empty
+-}
+drawChar :: (Monad m) => Parser Text m (Maybe Char)
+drawChar = do
+ x <- PP.draw
+ case x of
+ Nothing -> return Nothing
+ Just txt -> case (T.uncons txt) of
+ Nothing -> drawChar
+ Just (c, txt') -> do
+ PP.unDraw txt'
+ return (Just c)
+{-# INLINABLE drawChar #-}
+
+-- | Push back a 'Char' onto the underlying 'Producer'
+unDrawChar :: (Monad m) => Char -> Parser Text m ()
+unDrawChar c = modify (yield (T.singleton c) >>)
+{-# INLINABLE unDrawChar #-}
+
+{-| 'peekChar' checks the first 'Char' in the stream, but uses 'unDrawChar' to
+ push the 'Char' back
+
+> peekChar = do
+> x <- drawChar
+> case x of
+> Left _ -> return ()
+> Right c -> unDrawChar c
+> return x
+-}
+peekChar :: (Monad m) => Parser Text m (Maybe Char)
+peekChar = do
+ x <- drawChar
+ case x of
+ Nothing -> return ()
+ Just c -> unDrawChar c
+ return x
+{-# INLINABLE peekChar #-}
+
+{-| Check if the underlying 'Producer' has no more characters
+
+ Note that this will skip over empty 'Text' chunks, unlike
+ 'PP.isEndOfInput' from @pipes-parse@, which would consider
+ an empty 'Text' a valid bit of input.
+
+> isEndOfChars = liftM isLeft peekChar
+-}
+isEndOfChars :: (Monad m) => Parser Text m Bool
+isEndOfChars = do
+ x <- peekChar
+ return (case x of
+ Nothing -> True
+ Just _-> False )
+{-# INLINABLE isEndOfChars #-}
+
+
+{- | An improper lens into a stream of 'ByteString' expected to be UTF-8 encoded; the associated
+ stream of Text ends by returning a stream of ByteStrings beginning at the point of failure.
+ -}
+
+decodeUtf8 :: Monad m => Lens' (Producer ByteString m r)
+ (Producer Text m (Producer ByteString m r))
+decodeUtf8 k p0 = fmap (\p -> join (for p (yield . TE.encodeUtf8)))
+ (k (go B.empty PI.streamDecodeUtf8 p0)) where
go !carry dec0 p = do
x <- lift (next p)
- case x of Left r -> if B.null carry
- then return (return r) -- all bytestrinput was consumed
- else return (do yield carry -- a potentially valid fragment remains
- return r)
+ case x of Left r -> return (if B.null carry
+ then return r -- all bytestring input was consumed
+ else (do yield carry -- a potentially valid fragment remains
+ return r))
Right (chunk, p') -> case dec0 chunk of
- PE.Some text carry2 dec -> do yield text
+ PI.Some text carry2 dec -> do yield text
go carry2 dec p'
- PE.Other text bs -> do yield text
+ PI.Other text bs -> do yield text
return (do yield bs -- an invalid blob remains
p')
{-# INLINABLE decodeUtf8 #-}
splitAt
:: (Monad m, Integral n)
=> n
- -> Producer Text m r
- -> Producer' Text m (Producer Text m r)
-splitAt = go
+ -> Lens' (Producer Text m r)
+ (Producer Text m (Producer Text m r))
+splitAt n0 k p0 = fmap join (k (go n0 p0))
where
go 0 p = return p
go n p = do
return (yield suffix >> p')
{-# INLINABLE splitAt #-}
--- | Split a text stream into 'FreeT'-delimited text streams of fixed size
-chunksOf
- :: (Monad m, Integral n)
- => n -> Producer Text m r -> FreeT (Producer Text m) m r
-chunksOf n p0 = PP.FreeT (go p0)
- where
- go p = do
- x <- next p
- return $ case x of
- Left r -> PP.Pure r
- Right (txt, p') -> PP.Free $ do
- p'' <- splitAt n (yield txt >> p')
- return $ PP.FreeT (go p'')
-{-# INLINABLE chunksOf #-}
{-| Split a text stream in two, where the first text stream is the longest
consecutive group of text that satisfy the predicate
span
:: (Monad m)
=> (Char -> Bool)
- -> Producer Text m r
- -> Producer' Text m (Producer Text m r)
-span predicate = go
+ -> Lens' (Producer Text m r)
+ (Producer Text m (Producer Text m r))
+span predicate k p0 = fmap join (k (go p0))
where
go p = do
x <- lift (next p)
break
:: (Monad m)
=> (Char -> Bool)
- -> Producer Text m r
- -> Producer Text m (Producer Text m r)
+ -> Lens' (Producer Text m r)
+ (Producer Text m (Producer Text m r))
break predicate = span (not . predicate)
{-# INLINABLE break #-}
-{-| Split a text stream into sub-streams delimited by characters that satisfy the
- predicate
--}
-splitWith
- :: (Monad m)
- => (Char -> Bool)
- -> Producer Text m r
- -> PP.FreeT (Producer Text m) m r
-splitWith predicate p0 = PP.FreeT (go0 p0)
- where
- go0 p = do
- x <- next p
- case x of
- Left r -> return (PP.Pure r)
- Right (txt, p') ->
- if (T.null txt)
- then go0 p'
- else return $ PP.Free $ do
- p'' <- span (not . predicate) (yield txt >> p')
- return $ PP.FreeT (go1 p'')
- go1 p = do
- x <- nextChar p
- return $ case x of
- Left r -> PP.Pure r
- Right (_, p') -> PP.Free $ do
- p'' <- span (not . predicate) p'
- return $ PP.FreeT (go1 p'')
-{-# INLINABLE splitWith #-}
-
--- | Split a text stream using the given 'Char' as the delimiter
-split :: (Monad m)
- => Char
- -> Producer Text m r
- -> FreeT (Producer Text m) m r
-split c = splitWith (c ==)
-{-# INLINABLE split #-}
-
-{-| Group a text stream into 'FreeT'-delimited text streams using the supplied
- equality predicate
+{-| Improper lens that splits after the first group of equivalent Chars, as
+ defined by the given equivalence relation
-}
groupBy
:: (Monad m)
=> (Char -> Char -> Bool)
- -> Producer Text m r
- -> FreeT (Producer Text m) m r
-groupBy equal p0 = PP.FreeT (go p0)
- where
+ -> Lens' (Producer Text m r)
+ (Producer Text m (Producer Text m r))
+groupBy equals k p0 = fmap join (k ((go p0))) where
go p = do
- x <- next p
+ x <- lift (next p)
case x of
- Left r -> return (PP.Pure r)
- Right (txt, p') -> case (T.uncons txt) of
+ Left r -> return (return r)
+ Right (txt, p') -> case T.uncons txt of
Nothing -> go p'
- Just (c, _) -> do
- return $ PP.Free $ do
- p'' <- span (equal c) (yield txt >> p')
- return $ PP.FreeT (go p'')
+ Just (c, _) -> (yield txt >> p') ^. span (equals c)
{-# INLINABLE groupBy #-}
--- | Group a text stream into 'FreeT'-delimited text streams of identical characters
-group
- :: (Monad m) => Producer Text m r -> FreeT (Producer Text m) m r
+-- | Improper lens that splits after the first succession of identical 'Char' s
+group :: Monad m
+ => Lens' (Producer Text m r)
+ (Producer Text m (Producer Text m r))
group = groupBy (==)
{-# INLINABLE group #-}
-{-| Split a text stream into 'FreeT'-delimited lines
+{-| Improper lens that splits a 'Producer' after the first word
+
+ Unlike 'words', this does not drop leading whitespace
-}
-lines
- :: (Monad m) => Producer Text m r -> FreeT (Producer Text m) m r
-lines p0 = PP.FreeT (go0 p0)
+word :: (Monad m)
+ => Lens' (Producer Text m r)
+ (Producer Text m (Producer Text m r))
+word k p0 = fmap join (k (to p0))
where
- go0 p = do
- x <- next p
- case x of
- Left r -> return (PP.Pure r)
- Right (txt, p') ->
- if (T.null txt)
- then go0 p'
- else return $ PP.Free $ go1 (yield txt >> p')
- go1 p = do
- p' <- break ('\n' ==) p
- return $ PP.FreeT $ do
- x <- nextChar p'
- case x of
- Left r -> return $ PP.Pure r
- Right (_, p'') -> go0 p''
-{-# INLINABLE lines #-}
+ to p = do
+ p' <- p^.span isSpace
+ p'^.break isSpace
+{-# INLINABLE word #-}
+line :: (Monad m)
+ => Lens' (Producer Text m r)
+ (Producer Text m (Producer Text m r))
+line = break (== '\n')
--- | Split a text stream into 'FreeT'-delimited words
-words
- :: (Monad m) => Producer Text m r -> FreeT (Producer Text m) m r
-words = go
- where
- go p = PP.FreeT $ do
- x <- next (p >-> dropWhile isSpace)
- return $ case x of
- Left r -> PP.Pure r
- Right (bs, p') -> PP.Free $ do
- p'' <- break isSpace (yield bs >> p')
- return (go p'')
-{-# INLINABLE words #-}
+{-# INLINABLE line #-}
--- | Intersperse a 'Char' in between the characters of the text stream
+-- | Intersperse a 'Char' in between the characters of stream of 'Text'
intersperse
:: (Monad m) => Char -> Producer Text m r -> Producer Text m r
intersperse c = go0
go1 p'
{-# INLINABLE intersperse #-}
+
+
+-- | Improper isomorphism between a 'Producer' of 'ByteString's and 'Word8's
+packChars :: Monad m => Iso' (Producer Char m x) (Producer Text m x)
+packChars = Data.Profunctor.dimap to (fmap from)
+ where
+ -- to :: Monad m => Producer Char m x -> Producer Text m x
+ to p = PG.folds step id done (p^.PG.chunksOf defaultChunkSize)
+
+ step diffAs c = diffAs . (c:)
+
+ done diffAs = T.pack (diffAs [])
+
+ -- from :: Monad m => Producer Text m x -> Producer Char m x
+ from p = for p (each . T.unpack)
+{-# INLINABLE packChars #-}
+
+
+-- | Split a text stream into 'FreeT'-delimited text streams of fixed size
+chunksOf
+ :: (Monad m, Integral n)
+ => n -> Lens' (Producer Text m r)
+ (FreeT (Producer Text m) m r)
+chunksOf n k p0 = fmap concats (k (FreeT (go p0)))
+ where
+ go p = do
+ x <- next p
+ return $ case x of
+ Left r -> Pure r
+ Right (txt, p') -> Free $ do
+ p'' <- (yield txt >> p') ^. splitAt n
+ return $ FreeT (go p'')
+{-# INLINABLE chunksOf #-}
+
+
+{-| Split a text stream into sub-streams delimited by characters that satisfy the
+ predicate
+-}
+splitsWith
+ :: (Monad m)
+ => (Char -> Bool)
+ -> Producer Text m r
+ -> FreeT (Producer Text m) m r
+splitsWith predicate p0 = FreeT (go0 p0)
+ where
+ go0 p = do
+ x <- next p
+ case x of
+ Left r -> return (Pure r)
+ Right (txt, p') ->
+ if (T.null txt)
+ then go0 p'
+ else return $ Free $ do
+ p'' <- (yield txt >> p') ^. span (not . predicate)
+ return $ FreeT (go1 p'')
+ go1 p = do
+ x <- nextChar p
+ return $ case x of
+ Left r -> Pure r
+ Right (_, p') -> Free $ do
+ p'' <- p' ^. span (not . predicate)
+ return $ FreeT (go1 p'')
+{-# INLINABLE splitsWith #-}
+
+-- | Split a text stream using the given 'Char' as the delimiter
+splits :: (Monad m)
+ => Char
+ -> Lens' (Producer Text m r)
+ (FreeT (Producer Text m) m r)
+splits c k p =
+ fmap (PG.intercalates (yield (T.singleton c))) (k (splitsWith (c ==) p))
+{-# INLINABLE splits #-}
+
+{-| Isomorphism between a stream of 'Text' and groups of equivalent 'Char's , using the
+ given equivalence relation
+-}
+groupsBy
+ :: Monad m
+ => (Char -> Char -> Bool)
+ -> Lens' (Producer Text m x) (FreeT (Producer Text m) m x)
+groupsBy equals k p0 = fmap concats (k (FreeT (go p0))) where
+ go p = do x <- next p
+ case x of Left r -> return (Pure r)
+ Right (bs, p') -> case T.uncons bs of
+ Nothing -> go p'
+ Just (c, _) -> do return $ Free $ do
+ p'' <- (yield bs >> p')^.span (equals c)
+ return $ FreeT (go p'')
+{-# INLINABLE groupsBy #-}
+
+
+-- | Like 'groupsBy', where the equality predicate is ('==')
+groups
+ :: Monad m
+ => Lens' (Producer Text m x) (FreeT (Producer Text m) m x)
+groups = groupsBy (==)
+{-# INLINABLE groups #-}
+
+
+
+{-| Split a text stream into 'FreeT'-delimited lines
+-}
+lines
+ :: (Monad m) => Iso' (Producer Text m r) (FreeT (Producer Text m) m r)
+lines = Data.Profunctor.dimap _lines (fmap _unlines)
+ where
+ _lines p0 = FreeT (go0 p0)
+ where
+ go0 p = do
+ x <- next p
+ case x of
+ Left r -> return (Pure r)
+ Right (txt, p') ->
+ if (T.null txt)
+ then go0 p'
+ else return $ Free $ go1 (yield txt >> p')
+ go1 p = do
+ p' <- p ^. break ('\n' ==)
+ return $ FreeT $ do
+ x <- nextChar p'
+ case x of
+ Left r -> return $ Pure r
+ Right (_, p'') -> go0 p''
+ -- _unlines
+ -- :: Monad m
+ -- => FreeT (Producer Text m) m x -> Producer Text m x
+ _unlines = concats . PG.maps (<* yield (T.singleton '\n'))
+
+
+{-# INLINABLE lines #-}
+
+
+-- | Split a text stream into 'FreeT'-delimited words
+words
+ :: (Monad m) => Iso' (Producer Text m r) (FreeT (Producer Text m) m r)
+words = Data.Profunctor.dimap go (fmap _unwords)
+ where
+ go p = FreeT $ do
+ x <- next (p >-> dropWhile isSpace)
+ return $ case x of
+ Left r -> Pure r
+ Right (bs, p') -> Free $ do
+ p'' <- (yield bs >> p') ^. break isSpace
+ return (go p'')
+ _unwords = PG.intercalates (yield $ T.singleton ' ')
+
+{-# INLINABLE words #-}
+
+
{-| 'intercalate' concatenates the 'FreeT'-delimited text streams after
interspersing a text stream in between them
-}
intercalate p0 = go0
where
go0 f = do
- x <- lift (PP.runFreeT f)
+ x <- lift (runFreeT f)
case x of
- PP.Pure r -> return r
- PP.Free p -> do
+ Pure r -> return r
+ Free p -> do
f' <- p
go1 f'
go1 f = do
- x <- lift (PP.runFreeT f)
+ x <- lift (runFreeT f)
case x of
- PP.Pure r -> return r
- PP.Free p -> do
+ Pure r -> return r
+ Free p -> do
p0
f' <- p
go1 f'
unlines = go
where
go f = do
- x <- lift (PP.runFreeT f)
+ x <- lift (runFreeT f)
case x of
- PP.Pure r -> return r
- PP.Free p -> do
+ Pure r -> return r
+ Free p -> do
f' <- p
yield $ T.singleton '\n'
go f'
-}
unwords
:: (Monad m) => FreeT (Producer Text m) m r -> Producer Text m r
-unwords = intercalate (yield $ T.pack " ")
+unwords = intercalate (yield $ T.singleton ' ')
{-# INLINABLE unwords #-}
{- $parse
-}
{- $reexports
- @Pipes.Text.Parse@ re-exports 'nextChar', 'drawChar', 'unDrawChar', 'peekChar', and 'isEndOfChars'.
@Data.Text@ re-exports the 'Text' type.
- @Pipes.Parse@ re-exports 'input', 'concat', and 'FreeT' (the type).
+ @Pipes.Parse@ re-exports 'input', 'concat', 'FreeT' (the type) and the 'Parse' synonym.
-}
-
-
-decode :: Monad m => PE.Decoding -> Producer ByteString m r -> Producer Text m (Producer ByteString m r)
--- decode codec = go B.empty where
--- go extra p0 =
--- do x <- lift (next p0)
--- case x of Right (chunk, p) ->
--- do let (text, stuff) = codecDecode codec (B.append extra chunk)
--- yield text
--- case stuff of Right extra' -> go extra' p
--- Left (exc,bs) -> do yield text
--- return (do yield bs
--- p)
--- Left r -> return (do yield extra
--- return r)
-
-decode d p0 = case d of
- PE.Other txt bad -> do yield txt
- return (do yield bad
- p0)
- PE.Some txt extra dec -> do yield txt
- x <- lift (next p0)
- case x of Left r -> return (do yield extra
- return r)
- Right (chunk,p1) -> decode (dec chunk) p1
-
--- go !carry dec0 p = do
--- x <- lift (next p)
--- case x of Left r -> if B.null carry
--- then return (return r) -- all bytestrinput was consumed
--- else return (do yield carry -- a potentially valid fragment remains
--- return r)
---
--- Right (chunk, p') -> case dec0 chunk of
--- PE.Some text carry2 dec -> do yield text
--- go carry2 dec p'
--- PE.Other text bs -> do yield text
--- return (do yield bs -- an invalid blob remains
--- p')
--- {-# INLINABLE decodeUtf8 #-}
+{- | Use a 'Codec' as a pipes-style 'Lens' into a byte stream; the available 'Codec' s are
+ 'utf8', 'utf16_le', 'utf16_be', 'utf32_le', 'utf32_be' . The 'Codec' concept and the
+ individual 'Codec' definitions follow the enumerator and conduit libraries.
+
+ Utf8 is handled differently in this library -- without the use of 'unsafePerformIO' &co
+ to catch 'Text' exceptions; but the same 'mypipe ^. codec utf8' interface can be used.
+ 'mypipe ^. decodeUtf8' should be the same, but has a somewhat more direct and thus perhaps
+ better implementation.
+
+ -}
+codec :: Monad m => Codec -> Lens' (Producer ByteString m r) (Producer Text m (Producer ByteString m r))
+codec (Codec _ enc dec) k p0 = fmap (\p -> join (for p (yield . fst . enc)))
+ (k (decoder (dec B.empty) p0) ) where
+ decoder :: Monad m => PI.Decoding -> Producer ByteString m r -> Producer Text m (Producer ByteString m r)
+ decoder !d p0 = case d of
+ PI.Other txt bad -> do yield txt
+ return (do yield bad
+ p0)
+ PI.Some txt extra dec -> do yield txt
+ x <- lift (next p0)
+ case x of Left r -> return (do yield extra
+ return r)
+ Right (chunk,p1) -> decoder (dec chunk) p1
+
+{- | ascii and latin encodings only represent a small fragment of 'Text'; thus we cannot
+ use the pipes 'Lens' style to work with them. Rather we simply define functions
+ each way.
+
+ 'encodeAscii' : Reduce as much of your stream of 'Text' actually is ascii to a byte stream,
+ returning the rest of the 'Text' at the first non-ascii 'Char'
+-}
+encodeAscii :: Monad m => Producer Text m r -> Producer ByteString m (Producer Text m r)
+encodeAscii = go where
+ go p = do echunk <- lift (next p)
+ case echunk of
+ Left r -> return (return r)
+ Right (chunk, p') ->
+ if T.null chunk
+ then go p'
+ else let (safe, unsafe) = T.span (\c -> ord c <= 0x7F) chunk
+ in do yield (B8.pack (T.unpack safe))
+ if T.null unsafe
+ then go p'
+ else return $ do yield unsafe
+ p'
+{- | Reduce as much of your stream of 'Text' actually is iso8859 or latin1 to a byte stream,
+ returning the rest of the 'Text' upon hitting any non-latin 'Char'
+ -}
+encodeIso8859_1 :: Monad m => Producer Text m r -> Producer ByteString m (Producer Text m r)
+encodeIso8859_1 = go where
+ go p = do etxt <- lift (next p)
+ case etxt of
+ Left r -> return (return r)
+ Right (txt, p') ->
+ if T.null txt
+ then go p'
+ else let (safe, unsafe) = T.span (\c -> ord c <= 0xFF) txt
+ in do yield (B8.pack (T.unpack safe))
+ if T.null unsafe
+ then go p'
+ else return $ do yield unsafe
+ p'
+
+{- | Reduce a byte stream to a corresponding stream of ascii chars, returning the
+ unused 'ByteString' upon hitting an un-ascii byte.
+ -}
+decodeAscii :: Monad m => Producer ByteString m r -> Producer Text m (Producer ByteString m r)
+decodeAscii = go where
+ go p = do echunk <- lift (next p)
+ case echunk of
+ Left r -> return (return r)
+ Right (chunk, p') ->
+ if B.null chunk
+ then go p'
+ else let (safe, unsafe) = B.span (<= 0x7F) chunk
+ in do yield (T.pack (B8.unpack safe))
+ if B.null unsafe
+ then go p'
+ else return $ do yield unsafe
+ p'
+
+{- | Reduce a byte stream to a corresponding stream of ascii chars, returning the
+ unused 'ByteString' upon hitting the rare un-latinizable byte.
+ -}
+decodeIso8859_1 :: Monad m => Producer ByteString m r -> Producer Text m (Producer ByteString m r)
+decodeIso8859_1 = go where
+ go p = do echunk <- lift (next p)
+ case echunk of
+ Left r -> return (return r)
+ Right (chunk, p') ->
+ if B.null chunk
+ then go p'
+ else let (safe, unsafe) = B.span (<= 0xFF) chunk
+ in do yield (T.pack (B8.unpack safe))
+ if B.null unsafe
+ then go p'
+ else return $ do yield unsafe
+ p'
+
+
+
+
+
\ No newline at end of file
projects / github / fretlink / text-pipes.git / blobdiff