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author | michaelt <what_is_it_to_do_anything@yahoo.com> | 2013-10-04 22:12:06 -0400 |
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committer | michaelt <what_is_it_to_do_anything@yahoo.com> | 2013-10-04 22:12:06 -0400 |
commit | 91727d110a2f2278d166786831d984b51d47ac15 (patch) | |
tree | 001b0212c42adf240adfd782bbb09d8052e90b6d | |
parent | f33dd2aba8b118404988e536381ab0c4f61281fb (diff) | |
download | text-pipes-91727d110a2f2278d166786831d984b51d47ac15.tar.gz text-pipes-91727d110a2f2278d166786831d984b51d47ac15.tar.zst text-pipes-91727d110a2f2278d166786831d984b51d47ac15.zip |
shabby medley of Pipes-Bytestring + Pipes.Prelude
-rw-r--r-- | Data/Text/Pipes.hs | 863 | ||||
-rw-r--r-- | LICENSE | 30 | ||||
-rw-r--r-- | Setup.hs | 2 | ||||
-rw-r--r-- | text-pipes.cabal | 33 |
4 files changed, 928 insertions, 0 deletions
diff --git a/Data/Text/Pipes.hs b/Data/Text/Pipes.hs new file mode 100644 index 0000000..e9b5488 --- /dev/null +++ b/Data/Text/Pipes.hs | |||
@@ -0,0 +1,863 @@ | |||
1 | {-# LANGUAGE RankNTypes, TypeFamilies #-} | ||
2 | |||
3 | {-| This module provides @pipes@ utilities for \"byte streams\", which are | ||
4 | streams of strict 'Text's chunks. Use byte streams to interact | ||
5 | with both 'IO.Handle's and lazy 'Text's. | ||
6 | |||
7 | To stream to or from 'IO.Handle's, use 'fromHandle' or 'toHandle'. For | ||
8 | example, the following program copies data from one file to another: | ||
9 | |||
10 | > import Pipes | ||
11 | > import qualified Pipes.Text as P | ||
12 | > import System.IO | ||
13 | > | ||
14 | > main = | ||
15 | > withFile "inFile.txt" ReadMode $ \hIn -> | ||
16 | > withFile "outFile.txt" WriteMode $ \hOut -> | ||
17 | > runEffect $ P.fromHandle hIn >-> P.toHandle hOut | ||
18 | |||
19 | You can stream to and from 'stdin' and 'stdout' using the predefined 'stdin' | ||
20 | and 'stdout' proxies, like in the following \"echo\" program: | ||
21 | |||
22 | > main = runEffect $ P.stdin >-> P.stdout | ||
23 | |||
24 | You can also translate pure lazy 'TL.Text's to and from proxies: | ||
25 | |||
26 | > import qualified Data.Text.Lazy as TL | ||
27 | > | ||
28 | > main = runEffect $ P.fromLazy (TL.pack "Hello, world!\n") >-> P.stdout | ||
29 | |||
30 | In addition, this module provides many functions equivalent to lazy | ||
31 | 'Text' functions so that you can transform or fold byte streams. For | ||
32 | example, to stream only the first three lines of 'stdin' to 'stdout' you | ||
33 | would write: | ||
34 | |||
35 | > import Pipes | ||
36 | > import qualified Pipes.Text as PT | ||
37 | > import qualified Pipes.Parse as PP | ||
38 | > | ||
39 | > main = runEffect $ takeLines 3 PB.stdin >-> PT.stdout | ||
40 | > where | ||
41 | > takeLines n = PB.unlines . PP.takeFree n . PT.lines | ||
42 | |||
43 | The above program will never bring more than one chunk (~ 32 KB) into | ||
44 | memory, no matter how long the lines are. | ||
45 | |||
46 | Note that functions in this library are designed to operate on streams that | ||
47 | are insensitive to chunk boundaries. This means that they may freely split | ||
48 | chunks into smaller chunks and /discard empty chunks/. However, they will | ||
49 | /never concatenate chunks/ in order to provide strict upper bounds on memory | ||
50 | usage. | ||
51 | -} | ||
52 | |||
53 | module Data.Text.Pipes ( | ||
54 | -- * Producers | ||
55 | fromLazy, | ||
56 | stdin, | ||
57 | fromHandle, | ||
58 | readFile, | ||
59 | stdinLn, | ||
60 | -- hGetSome, | ||
61 | -- hGet, | ||
62 | |||
63 | -- * Servers | ||
64 | -- hGetSomeN, | ||
65 | -- hGetN, | ||
66 | |||
67 | -- * Consumers | ||
68 | stdout, | ||
69 | stdoutLn, | ||
70 | toHandle, | ||
71 | writeFile, | ||
72 | |||
73 | -- * Pipes | ||
74 | map, | ||
75 | concatMap, | ||
76 | take, | ||
77 | drop, | ||
78 | takeWhile, | ||
79 | dropWhile, | ||
80 | filter, | ||
81 | -- elemIndices, | ||
82 | -- findIndices, | ||
83 | scan, | ||
84 | |||
85 | -- * Folds | ||
86 | toLazy, | ||
87 | toLazyM, | ||
88 | fold, | ||
89 | head, | ||
90 | last, | ||
91 | null, | ||
92 | length, | ||
93 | any, | ||
94 | all, | ||
95 | maximum, | ||
96 | minimum, | ||
97 | -- elem, | ||
98 | -- notElem, | ||
99 | find, | ||
100 | index, | ||
101 | -- elemIndex, | ||
102 | -- findIndex, | ||
103 | -- count, | ||
104 | |||
105 | -- * Splitters | ||
106 | splitAt, | ||
107 | chunksOf, | ||
108 | span, | ||
109 | break, | ||
110 | splitWith, | ||
111 | split, | ||
112 | groupBy, | ||
113 | group, | ||
114 | lines, | ||
115 | words, | ||
116 | |||
117 | -- * Transformations | ||
118 | intersperse, | ||
119 | |||
120 | -- * Joiners | ||
121 | intercalate, | ||
122 | unlines, | ||
123 | unwords, | ||
124 | |||
125 | -- * Low-level Parsers | ||
126 | -- $parse | ||
127 | nextByte, | ||
128 | drawByte, | ||
129 | unDrawByte, | ||
130 | peekByte, | ||
131 | isEndOfBytes, | ||
132 | -- takeWhile', | ||
133 | |||
134 | -- * Re-exports | ||
135 | -- $reexports | ||
136 | module Data.Text, | ||
137 | -- module Data.Word, | ||
138 | module Pipes.Parse | ||
139 | ) where | ||
140 | |||
141 | import Control.Exception (throwIO, try) | ||
142 | import Control.Monad (liftM, unless) | ||
143 | import Control.Monad.Trans.State.Strict (StateT) | ||
144 | import qualified Data.Text as T | ||
145 | import qualified Data.Text.IO as T | ||
146 | import Data.Text (Text) | ||
147 | import qualified Data.Text.Lazy as TL | ||
148 | import qualified Data.Text.Lazy.IO as TL | ||
149 | import Data.Text.Lazy.Internal (foldrChunks, defaultChunkSize) | ||
150 | import Data.ByteString.Unsafe (unsafeTake, unsafeDrop) | ||
151 | import Data.Char (ord) | ||
152 | import Data.Functor.Identity (Identity) | ||
153 | import qualified Data.List as List | ||
154 | import Foreign.C.Error (Errno(Errno), ePIPE) | ||
155 | import qualified GHC.IO.Exception as G | ||
156 | import Pipes | ||
157 | import qualified Pipes.ByteString.Parse as PBP | ||
158 | import Pipes.ByteString.Parse ( | ||
159 | nextByte, drawByte, unDrawByte, peekByte, isEndOfBytes ) | ||
160 | import Pipes.Core (respond, Server') | ||
161 | import qualified Pipes.Parse as PP | ||
162 | import Pipes.Parse (input, concat, FreeT) | ||
163 | import qualified Pipes.Safe.Prelude as Safe | ||
164 | import qualified Pipes.Safe as Safe | ||
165 | import Pipes.Safe (MonadSafe(..), Base(..)) | ||
166 | import qualified Pipes.Prelude as P | ||
167 | import qualified System.IO as IO | ||
168 | import Data.Char (isSpace) | ||
169 | import Prelude hiding ( | ||
170 | all, | ||
171 | any, | ||
172 | break, | ||
173 | concat, | ||
174 | concatMap, | ||
175 | drop, | ||
176 | dropWhile, | ||
177 | elem, | ||
178 | filter, | ||
179 | head, | ||
180 | last, | ||
181 | lines, | ||
182 | length, | ||
183 | map, | ||
184 | maximum, | ||
185 | minimum, | ||
186 | notElem, | ||
187 | null, | ||
188 | readFile, | ||
189 | span, | ||
190 | splitAt, | ||
191 | take, | ||
192 | takeWhile, | ||
193 | unlines, | ||
194 | unwords, | ||
195 | words, | ||
196 | writeFile ) | ||
197 | |||
198 | -- | Convert a lazy 'TL.Text' into a 'Producer' of strict 'Text's | ||
199 | fromLazy :: (Monad m) => TL.Text -> Producer' Text m () | ||
200 | fromLazy = foldrChunks (\e a -> yield e >> a) (return ()) | ||
201 | {-# INLINABLE fromLazy #-} | ||
202 | |||
203 | -- | Stream bytes from 'stdin' | ||
204 | stdin :: MonadIO m => Producer' Text m () | ||
205 | stdin = fromHandle IO.stdin | ||
206 | {-# INLINABLE stdin #-} | ||
207 | |||
208 | -- | Convert a 'IO.Handle' into a byte stream using a default chunk size | ||
209 | fromHandle :: MonadIO m => IO.Handle -> Producer' Text m () | ||
210 | fromHandle h = go where | ||
211 | go = do txt <- liftIO (T.hGetChunk h) | ||
212 | unless (T.null txt) $ do yield txt | ||
213 | go | ||
214 | {-# INLINABLE fromHandle#-} | ||
215 | |||
216 | readFile :: (MonadSafe m, Base m ~ IO) => FilePath -> Producer' Text m () | ||
217 | readFile file = Safe.withFile file IO.ReadMode fromHandle | ||
218 | {-# INLINABLE readFile #-} | ||
219 | |||
220 | stdinLn :: MonadIO m => Producer' Text m () | ||
221 | stdinLn = go | ||
222 | where | ||
223 | go = do | ||
224 | eof <- liftIO (IO.hIsEOF IO.stdin) | ||
225 | unless eof $ do | ||
226 | txt <- liftIO (T.hGetLine IO.stdin) | ||
227 | yield txt | ||
228 | go | ||
229 | |||
230 | {-| Convert a handle into a byte stream using a fixed chunk size | ||
231 | |||
232 | 'hGet' waits until exactly the requested number of bytes are available for | ||
233 | each chunk. | ||
234 | -} | ||
235 | -- hGet :: MonadIO m => Int -> IO.Handle -> Producer' Text m () | ||
236 | -- hGet size h = go where | ||
237 | -- go = do | ||
238 | -- eof <- liftIO (IO.hIsEOF h) | ||
239 | -- if eof | ||
240 | -- then return () | ||
241 | -- else do | ||
242 | -- bs <- liftIO (T.hGet h size) | ||
243 | -- yield bs | ||
244 | -- go | ||
245 | -- {-# INLINABLE hGet #-} | ||
246 | |||
247 | {-| Like 'hGetSome', except you can vary the maximum chunk size for each request | ||
248 | -} | ||
249 | -- hGetSomeN :: MonadIO m => IO.Handle -> Int -> Server' Int Text m () | ||
250 | -- hGetSomeN h = go where | ||
251 | -- go size = do | ||
252 | -- eof <- liftIO (IO.hIsEOF h) | ||
253 | -- if eof | ||
254 | -- then return () | ||
255 | -- else do | ||
256 | -- bs <- liftIO (T.hGetSome h size) | ||
257 | -- size2 <- respond bs | ||
258 | -- go size2 | ||
259 | -- {-# INLINABLE hGetSomeN #-} | ||
260 | -- | ||
261 | -- -- | Like 'hGet', except you can vary the chunk size for each request | ||
262 | -- hGetN :: MonadIO m => IO.Handle -> Int -> Server' Int Text m () | ||
263 | -- hGetN h = go where | ||
264 | -- go size = do | ||
265 | -- eof <- liftIO (IO.hIsEOF h) | ||
266 | -- if eof | ||
267 | -- then return () | ||
268 | -- else do | ||
269 | -- bs <- liftIO (T.hGet h size) | ||
270 | -- size2 <- respond bs | ||
271 | -- go size2 | ||
272 | -- {-# INLINABLE hGetN #-} | ||
273 | |||
274 | {-| Stream bytes to 'stdout' | ||
275 | |||
276 | Unlike 'toHandle', 'stdout' gracefully terminates on a broken output pipe. | ||
277 | |||
278 | Note: For best performance, use @(for source (liftIO . putStr))@ instead of | ||
279 | @(source >-> stdout)@. | ||
280 | -} | ||
281 | stdout :: MonadIO m => Consumer' Text m () | ||
282 | stdout = go | ||
283 | where | ||
284 | go = do | ||
285 | txt <- await | ||
286 | x <- liftIO $ try (T.putStr txt) | ||
287 | case x of | ||
288 | Left (G.IOError { G.ioe_type = G.ResourceVanished | ||
289 | , G.ioe_errno = Just ioe }) | ||
290 | | Errno ioe == ePIPE | ||
291 | -> return () | ||
292 | Left e -> liftIO (throwIO e) | ||
293 | Right () -> go | ||
294 | {-# INLINABLE stdout #-} | ||
295 | |||
296 | stdoutLn :: (MonadIO m) => Consumer' Text m () | ||
297 | stdoutLn = go | ||
298 | where | ||
299 | go = do | ||
300 | str <- await | ||
301 | x <- liftIO $ try (T.putStrLn str) | ||
302 | case x of | ||
303 | Left (G.IOError { G.ioe_type = G.ResourceVanished | ||
304 | , G.ioe_errno = Just ioe }) | ||
305 | | Errno ioe == ePIPE | ||
306 | -> return () | ||
307 | Left e -> liftIO (throwIO e) | ||
308 | Right () -> go | ||
309 | {-# INLINABLE stdoutLn #-} | ||
310 | |||
311 | {-| Convert a byte stream into a 'Handle' | ||
312 | |||
313 | Note: For best performance, use @(for source (liftIO . hPutStr handle))@ | ||
314 | instead of @(source >-> toHandle handle)@. | ||
315 | -} | ||
316 | toHandle :: MonadIO m => IO.Handle -> Consumer' Text m r | ||
317 | toHandle h = for cat (liftIO . T.hPutStr h) | ||
318 | {-# INLINABLE toHandle #-} | ||
319 | |||
320 | writeFile :: (MonadSafe m, Base m ~ IO) => FilePath -> Consumer' Text m () | ||
321 | writeFile file = Safe.withFile file IO.WriteMode toHandle | ||
322 | |||
323 | -- | Apply a transformation to each 'Char' in the stream | ||
324 | map :: (Monad m) => (Char -> Char) -> Pipe Text Text m r | ||
325 | map f = P.map (T.map f) | ||
326 | {-# INLINABLE map #-} | ||
327 | |||
328 | -- | Map a function over the byte stream and concatenate the results | ||
329 | concatMap | ||
330 | :: (Monad m) => (Char -> Text) -> Pipe Text Text m r | ||
331 | concatMap f = P.map (T.concatMap f) | ||
332 | {-# INLINABLE concatMap #-} | ||
333 | |||
334 | -- | @(take n)@ only allows @n@ bytes to pass | ||
335 | take :: (Monad m, Integral a) => a -> Pipe Text Text m () | ||
336 | take n0 = go n0 where | ||
337 | go n | ||
338 | | n <= 0 = return () | ||
339 | | otherwise = do | ||
340 | bs <- await | ||
341 | let len = fromIntegral (T.length bs) | ||
342 | if (len > n) | ||
343 | then yield (T.take (fromIntegral n) bs) | ||
344 | else do | ||
345 | yield bs | ||
346 | go (n - len) | ||
347 | {-# INLINABLE take #-} | ||
348 | |||
349 | -- | @(dropD n)@ drops the first @n@ bytes | ||
350 | drop :: (Monad m, Integral a) => a -> Pipe Text Text m r | ||
351 | drop n0 = go n0 where | ||
352 | go n | ||
353 | | n <= 0 = cat | ||
354 | | otherwise = do | ||
355 | bs <- await | ||
356 | let len = fromIntegral (T.length bs) | ||
357 | if (len >= n) | ||
358 | then do | ||
359 | yield (T.drop (fromIntegral n) bs) | ||
360 | cat | ||
361 | else go (n - len) | ||
362 | {-# INLINABLE drop #-} | ||
363 | |||
364 | -- | Take bytes until they fail the predicate | ||
365 | takeWhile :: (Monad m) => (Char -> Bool) -> Pipe Text Text m () | ||
366 | takeWhile predicate = go | ||
367 | where | ||
368 | go = do | ||
369 | bs <- await | ||
370 | let (prefix, suffix) = T.span predicate bs | ||
371 | if (T.null suffix) | ||
372 | then do | ||
373 | yield bs | ||
374 | go | ||
375 | else yield prefix | ||
376 | {-# INLINABLE takeWhile #-} | ||
377 | |||
378 | -- | Drop bytes until they fail the predicate | ||
379 | dropWhile :: (Monad m) => (Char -> Bool) -> Pipe Text Text m r | ||
380 | dropWhile predicate = go where | ||
381 | go = do | ||
382 | bs <- await | ||
383 | case T.findIndex (not . predicate) bs of | ||
384 | Nothing -> go | ||
385 | Just i -> do | ||
386 | yield (T.drop i bs) | ||
387 | cat | ||
388 | {-# INLINABLE dropWhile #-} | ||
389 | |||
390 | -- | Only allows 'Char's to pass if they satisfy the predicate | ||
391 | filter :: (Monad m) => (Char -> Bool) -> Pipe Text Text m r | ||
392 | filter predicate = P.map (T.filter predicate) | ||
393 | {-# INLINABLE filter #-} | ||
394 | |||
395 | -- | Stream all indices whose elements match the given 'Char' | ||
396 | -- elemIndices :: (Monad m, Num n) => Char -> Pipe Text n m r | ||
397 | -- elemIndices w8 = findIndices (w8 ==) | ||
398 | -- {-# INLINABLE elemIndices #-} | ||
399 | |||
400 | -- | Stream all indices whose elements satisfy the given predicate | ||
401 | -- findIndices :: (Monad m, Num n) => (Char -> Bool) -> Pipe Text n m r | ||
402 | -- findIndices predicate = go 0 | ||
403 | -- where | ||
404 | -- go n = do | ||
405 | -- bs <- await | ||
406 | -- each $ List.map (\i -> n + fromIntegral i) (T.findIndices predicate bs) | ||
407 | -- go $! n + fromIntegral (T.length bs) | ||
408 | -- {-# INLINABLE findIndices #-} | ||
409 | |||
410 | -- | Strict left scan over the bytes | ||
411 | scan | ||
412 | :: (Monad m) | ||
413 | => (Char -> Char -> Char) -> Char -> Pipe Text Text m r | ||
414 | scan step begin = go begin | ||
415 | where | ||
416 | go w8 = do | ||
417 | bs <- await | ||
418 | let bs' = T.scanl step w8 bs | ||
419 | w8' = T.last bs' | ||
420 | yield bs' | ||
421 | go w8' | ||
422 | {-# INLINABLE scan #-} | ||
423 | |||
424 | {-| Fold a pure 'Producer' of strict 'Text's into a lazy | ||
425 | 'TL.Text' | ||
426 | -} | ||
427 | toLazy :: Producer Text Identity () -> TL.Text | ||
428 | toLazy = TL.fromChunks . P.toList | ||
429 | {-# INLINABLE toLazy #-} | ||
430 | |||
431 | {-| Fold an effectful 'Producer' of strict 'Text's into a lazy | ||
432 | 'TL.Text' | ||
433 | |||
434 | Note: 'toLazyM' is not an idiomatic use of @pipes@, but I provide it for | ||
435 | simple testing purposes. Idiomatic @pipes@ style consumes the chunks | ||
436 | immediately as they are generated instead of loading them all into memory. | ||
437 | -} | ||
438 | toLazyM :: (Monad m) => Producer Text m () -> m TL.Text | ||
439 | toLazyM = liftM TL.fromChunks . P.toListM | ||
440 | {-# INLINABLE toLazyM #-} | ||
441 | |||
442 | -- | Reduce the stream of bytes using a strict left fold | ||
443 | fold | ||
444 | :: Monad m | ||
445 | => (x -> Char -> x) -> x -> (x -> r) -> Producer Text m () -> m r | ||
446 | fold step begin done = P.fold (\x bs -> T.foldl' step x bs) begin done | ||
447 | {-# INLINABLE fold #-} | ||
448 | |||
449 | -- | Retrieve the first 'Char' | ||
450 | head :: (Monad m) => Producer Text m () -> m (Maybe Char) | ||
451 | head = go | ||
452 | where | ||
453 | go p = do | ||
454 | x <- nextChar p | ||
455 | case x of | ||
456 | Left _ -> return Nothing | ||
457 | Right (w8, _) -> return (Just w8) | ||
458 | {-# INLINABLE head #-} | ||
459 | |||
460 | -- | Retrieve the last 'Char' | ||
461 | last :: (Monad m) => Producer Text m () -> m (Maybe Char) | ||
462 | last = go Nothing | ||
463 | where | ||
464 | go r p = do | ||
465 | x <- next p | ||
466 | case x of | ||
467 | Left () -> return r | ||
468 | Right (bs, p') -> | ||
469 | if (T.null bs) | ||
470 | then go r p' | ||
471 | else go (Just $ T.last bs) p' | ||
472 | -- TODO: Change this to 'unsafeLast' when bytestring-0.10.2.0 | ||
473 | -- becomes more widespread | ||
474 | {-# INLINABLE last #-} | ||
475 | |||
476 | -- | Determine if the stream is empty | ||
477 | null :: (Monad m) => Producer Text m () -> m Bool | ||
478 | null = P.all T.null | ||
479 | {-# INLINABLE null #-} | ||
480 | |||
481 | -- | Count the number of bytes | ||
482 | length :: (Monad m, Num n) => Producer Text m () -> m n | ||
483 | length = P.fold (\n bs -> n + fromIntegral (T.length bs)) 0 id | ||
484 | {-# INLINABLE length #-} | ||
485 | |||
486 | -- | Fold that returns whether 'M.Any' received 'Char's satisfy the predicate | ||
487 | any :: (Monad m) => (Char -> Bool) -> Producer Text m () -> m Bool | ||
488 | any predicate = P.any (T.any predicate) | ||
489 | {-# INLINABLE any #-} | ||
490 | |||
491 | -- | Fold that returns whether 'M.All' received 'Char's satisfy the predicate | ||
492 | all :: (Monad m) => (Char -> Bool) -> Producer Text m () -> m Bool | ||
493 | all predicate = P.all (T.all predicate) | ||
494 | {-# INLINABLE all #-} | ||
495 | |||
496 | -- | Return the maximum 'Char' within a byte stream | ||
497 | maximum :: (Monad m) => Producer Text m () -> m (Maybe Char) | ||
498 | maximum = P.fold step Nothing id | ||
499 | where | ||
500 | step mw8 bs = | ||
501 | if (T.null bs) | ||
502 | then mw8 | ||
503 | else Just $ case mw8 of | ||
504 | Nothing -> T.maximum bs | ||
505 | Just w8 -> max w8 (T.maximum bs) | ||
506 | {-# INLINABLE maximum #-} | ||
507 | |||
508 | -- | Return the minimum 'Char' within a byte stream | ||
509 | minimum :: (Monad m) => Producer Text m () -> m (Maybe Char) | ||
510 | minimum = P.fold step Nothing id | ||
511 | where | ||
512 | step mw8 bs = | ||
513 | if (T.null bs) | ||
514 | then mw8 | ||
515 | else case mw8 of | ||
516 | Nothing -> Just (T.minimum bs) | ||
517 | Just w8 -> Just (min w8 (T.minimum bs)) | ||
518 | {-# INLINABLE minimum #-} | ||
519 | |||
520 | -- | Determine whether any element in the byte stream matches the given 'Char' | ||
521 | -- elem :: (Monad m) => Char -> Producer Text m () -> m Bool | ||
522 | -- elem w8 = P.any (T.elem w8) | ||
523 | -- {-# INLINABLE elem #-} | ||
524 | -- | ||
525 | -- {-| Determine whether all elements in the byte stream do not match the given | ||
526 | -- 'Char' | ||
527 | -- -} | ||
528 | -- notElem :: (Monad m) => Char -> Producer Text m () -> m Bool | ||
529 | -- notElem w8 = P.all (T.notElem w8) | ||
530 | -- {-# INLINABLE notElem #-} | ||
531 | |||
532 | -- | Find the first element in the stream that matches the predicate | ||
533 | find | ||
534 | :: (Monad m) | ||
535 | => (Char -> Bool) -> Producer Text m () -> m (Maybe Char) | ||
536 | find predicate p = head (p >-> filter predicate) | ||
537 | {-# INLINABLE find #-} | ||
538 | |||
539 | -- | Index into a byte stream | ||
540 | index | ||
541 | :: (Monad m, Integral a) | ||
542 | => a-> Producer Text m () -> m (Maybe Char) | ||
543 | index n p = head (p >-> drop n) | ||
544 | {-# INLINABLE index #-} | ||
545 | |||
546 | -- | Find the index of an element that matches the given 'Char' | ||
547 | -- elemIndex | ||
548 | -- :: (Monad m, Num n) => Char -> Producer Text m () -> m (Maybe n) | ||
549 | -- elemIndex w8 = findIndex (w8 ==) | ||
550 | -- {-# INLINABLE elemIndex #-} | ||
551 | |||
552 | -- | Store the first index of an element that satisfies the predicate | ||
553 | -- findIndex | ||
554 | -- :: (Monad m, Num n) | ||
555 | -- => (Char -> Bool) -> Producer Text m () -> m (Maybe n) | ||
556 | -- findIndex predicate p = P.head (p >-> findIndices predicate) | ||
557 | -- {-# INLINABLE findIndex #-} | ||
558 | -- | ||
559 | -- -- | Store a tally of how many elements match the given 'Char' | ||
560 | -- count :: (Monad m, Num n) => Char -> Producer Text m () -> m n | ||
561 | -- count w8 p = P.fold (+) 0 id (p >-> P.map (fromIntegral . T.count w8)) | ||
562 | -- {-# INLINABLE count #-} | ||
563 | |||
564 | -- | Splits a 'Producer' after the given number of bytes | ||
565 | splitAt | ||
566 | :: (Monad m, Integral n) | ||
567 | => n | ||
568 | -> Producer Text m r | ||
569 | -> Producer' Text m (Producer Text m r) | ||
570 | splitAt = go | ||
571 | where | ||
572 | go 0 p = return p | ||
573 | go n p = do | ||
574 | x <- lift (next p) | ||
575 | case x of | ||
576 | Left r -> return (return r) | ||
577 | Right (bs, p') -> do | ||
578 | let len = fromIntegral (T.length bs) | ||
579 | if (len <= n) | ||
580 | then do | ||
581 | yield bs | ||
582 | go (n - len) p' | ||
583 | else do | ||
584 | let (prefix, suffix) = T.splitAt (fromIntegral n) bs | ||
585 | yield prefix | ||
586 | return (yield suffix >> p') | ||
587 | {-# INLINABLE splitAt #-} | ||
588 | |||
589 | -- | Split a byte stream into 'FreeT'-delimited byte streams of fixed size | ||
590 | chunksOf | ||
591 | :: (Monad m, Integral n) | ||
592 | => n -> Producer Text m r -> FreeT (Producer Text m) m r | ||
593 | chunksOf n p0 = PP.FreeT (go p0) | ||
594 | where | ||
595 | go p = do | ||
596 | x <- next p | ||
597 | return $ case x of | ||
598 | Left r -> PP.Pure r | ||
599 | Right (bs, p') -> PP.Free $ do | ||
600 | p'' <- splitAt n (yield bs >> p') | ||
601 | return $ PP.FreeT (go p'') | ||
602 | {-# INLINABLE chunksOf #-} | ||
603 | |||
604 | {-| Split a byte stream in two, where the first byte stream is the longest | ||
605 | consecutive group of bytes that satisfy the predicate | ||
606 | -} | ||
607 | span | ||
608 | :: (Monad m) | ||
609 | => (Char -> Bool) | ||
610 | -> Producer Text m r | ||
611 | -> Producer' Text m (Producer Text m r) | ||
612 | span predicate = go | ||
613 | where | ||
614 | go p = do | ||
615 | x <- lift (next p) | ||
616 | case x of | ||
617 | Left r -> return (return r) | ||
618 | Right (bs, p') -> do | ||
619 | let (prefix, suffix) = T.span predicate bs | ||
620 | if (T.null suffix) | ||
621 | then do | ||
622 | yield bs | ||
623 | go p' | ||
624 | else do | ||
625 | yield prefix | ||
626 | return (yield suffix >> p') | ||
627 | {-# INLINABLE span #-} | ||
628 | |||
629 | {-| Split a byte stream in two, where the first byte stream is the longest | ||
630 | consecutive group of bytes that don't satisfy the predicate | ||
631 | -} | ||
632 | break | ||
633 | :: (Monad m) | ||
634 | => (Char -> Bool) | ||
635 | -> Producer Text m r | ||
636 | -> Producer Text m (Producer Text m r) | ||
637 | break predicate = span (not . predicate) | ||
638 | {-# INLINABLE break #-} | ||
639 | |||
640 | {-| Split a byte stream into sub-streams delimited by bytes that satisfy the | ||
641 | predicate | ||
642 | -} | ||
643 | splitWith | ||
644 | :: (Monad m) | ||
645 | => (Char -> Bool) | ||
646 | -> Producer Text m r | ||
647 | -> PP.FreeT (Producer Text m) m r | ||
648 | splitWith predicate p0 = PP.FreeT (go0 p0) | ||
649 | where | ||
650 | go0 p = do | ||
651 | x <- next p | ||
652 | case x of | ||
653 | Left r -> return (PP.Pure r) | ||
654 | Right (bs, p') -> | ||
655 | if (T.null bs) | ||
656 | then go0 p' | ||
657 | else return $ PP.Free $ do | ||
658 | p'' <- span (not . predicate) (yield bs >> p') | ||
659 | return $ PP.FreeT (go1 p'') | ||
660 | go1 p = do | ||
661 | x <- nextChar p | ||
662 | return $ case x of | ||
663 | Left r -> PP.Pure r | ||
664 | Right (_, p') -> PP.Free $ do | ||
665 | p'' <- span (not . predicate) p' | ||
666 | return $ PP.FreeT (go1 p'') | ||
667 | {-# INLINABLE splitWith #-} | ||
668 | |||
669 | -- | Split a byte stream using the given 'Char' as the delimiter | ||
670 | split :: (Monad m) | ||
671 | => Char | ||
672 | -> Producer Text m r | ||
673 | -> FreeT (Producer Text m) m r | ||
674 | split w8 = splitWith (w8 ==) | ||
675 | {-# INLINABLE split #-} | ||
676 | |||
677 | {-| Group a byte stream into 'FreeT'-delimited byte streams using the supplied | ||
678 | equality predicate | ||
679 | -} | ||
680 | groupBy | ||
681 | :: (Monad m) | ||
682 | => (Char -> Char -> Bool) | ||
683 | -> Producer Text m r | ||
684 | -> FreeT (Producer Text m) m r | ||
685 | groupBy equal p0 = PP.FreeT (go p0) | ||
686 | where | ||
687 | go p = do | ||
688 | x <- next p | ||
689 | case x of | ||
690 | Left r -> return (PP.Pure r) | ||
691 | Right (bs, p') -> case (T.uncons bs) of | ||
692 | Nothing -> go p' | ||
693 | Just (w8, _) -> do | ||
694 | return $ PP.Free $ do | ||
695 | p'' <- span (equal w8) (yield bs >> p') | ||
696 | return $ PP.FreeT (go p'') | ||
697 | {-# INLINABLE groupBy #-} | ||
698 | |||
699 | -- | Group a byte stream into 'FreeT'-delimited byte streams of identical bytes | ||
700 | group | ||
701 | :: (Monad m) => Producer Text m r -> FreeT (Producer Text m) m r | ||
702 | group = groupBy (==) | ||
703 | {-# INLINABLE group #-} | ||
704 | |||
705 | {-| Split a byte stream into 'FreeT'-delimited lines | ||
706 | |||
707 | Note: This function is purely for demonstration purposes since it assumes a | ||
708 | particular encoding. You should prefer the 'Data.Text.Text' equivalent of | ||
709 | this function from the upcoming @pipes-text@ library. | ||
710 | -} | ||
711 | lines | ||
712 | :: (Monad m) => Producer Text m r -> FreeT (Producer Text m) m r | ||
713 | lines p0 = PP.FreeT (go0 p0) | ||
714 | where | ||
715 | go0 p = do | ||
716 | x <- next p | ||
717 | case x of | ||
718 | Left r -> return (PP.Pure r) | ||
719 | Right (bs, p') -> | ||
720 | if (T.null bs) | ||
721 | then go0 p' | ||
722 | else return $ PP.Free $ go1 (yield bs >> p') | ||
723 | go1 p = do | ||
724 | p' <- break ('\n' ==) p | ||
725 | return $ PP.FreeT (go2 p') | ||
726 | go2 p = do | ||
727 | x <- nextChar p | ||
728 | return $ case x of | ||
729 | Left r -> PP.Pure r | ||
730 | Right (_, p') -> PP.Free (go1 p') | ||
731 | {-# INLINABLE lines #-} | ||
732 | nextChar = undefined | ||
733 | {-| Split a byte stream into 'FreeT'-delimited words | ||
734 | |||
735 | Note: This function is purely for demonstration purposes since it assumes a | ||
736 | particular encoding. You should prefer the 'Data.Text.Text' equivalent of | ||
737 | this function from the upcoming @pipes-text@ library. | ||
738 | -} | ||
739 | words | ||
740 | :: (Monad m) => Producer Text m r -> FreeT (Producer Text m) m r | ||
741 | words p0 = removeEmpty (splitWith isSpace p0) | ||
742 | where | ||
743 | removeEmpty f = PP.FreeT $ do | ||
744 | x <- PP.runFreeT f | ||
745 | case x of | ||
746 | PP.Pure r -> return (PP.Pure r) | ||
747 | PP.Free p -> do | ||
748 | y <- next p | ||
749 | case y of | ||
750 | Left f' -> PP.runFreeT (removeEmpty f') | ||
751 | Right (bs, p') -> return $ PP.Free $ do | ||
752 | yield bs | ||
753 | f' <- p' | ||
754 | return (removeEmpty f') | ||
755 | {-# INLINABLE words #-} | ||
756 | |||
757 | -- | Intersperse a 'Char' in between the bytes of the byte stream | ||
758 | intersperse | ||
759 | :: (Monad m) => Char -> Producer Text m r -> Producer Text m r | ||
760 | intersperse w8 = go0 | ||
761 | where | ||
762 | go0 p = do | ||
763 | x <- lift (next p) | ||
764 | case x of | ||
765 | Left r -> return r | ||
766 | Right (bs, p') -> do | ||
767 | yield (T.intersperse w8 bs) | ||
768 | go1 p' | ||
769 | go1 p = do | ||
770 | x <- lift (next p) | ||
771 | case x of | ||
772 | Left r -> return r | ||
773 | Right (bs, p') -> do | ||
774 | yield (T.singleton w8) | ||
775 | yield (T.intersperse w8 bs) | ||
776 | go1 p' | ||
777 | {-# INLINABLE intersperse #-} | ||
778 | |||
779 | {-| 'intercalate' concatenates the 'FreeT'-delimited byte streams after | ||
780 | interspersing a byte stream in between them | ||
781 | -} | ||
782 | intercalate | ||
783 | :: (Monad m) | ||
784 | => Producer Text m () | ||
785 | -> FreeT (Producer Text m) m r | ||
786 | -> Producer Text m r | ||
787 | intercalate p0 = go0 | ||
788 | where | ||
789 | go0 f = do | ||
790 | x <- lift (PP.runFreeT f) | ||
791 | case x of | ||
792 | PP.Pure r -> return r | ||
793 | PP.Free p -> do | ||
794 | f' <- p | ||
795 | go1 f' | ||
796 | go1 f = do | ||
797 | x <- lift (PP.runFreeT f) | ||
798 | case x of | ||
799 | PP.Pure r -> return r | ||
800 | PP.Free p -> do | ||
801 | p0 | ||
802 | f' <- p | ||
803 | go1 f' | ||
804 | {-# INLINABLE intercalate #-} | ||
805 | |||
806 | {-| Join 'FreeT'-delimited lines into a byte stream | ||
807 | |||
808 | Note: This function is purely for demonstration purposes since it assumes a | ||
809 | particular encoding. You should prefer the 'Data.Text.Text' equivalent of | ||
810 | this function from the upcoming @pipes-text@ library. | ||
811 | -} | ||
812 | unlines | ||
813 | :: (Monad m) => FreeT (Producer Text m) m r -> Producer Text m r | ||
814 | unlines = go | ||
815 | where | ||
816 | go f = do | ||
817 | x <- lift (PP.runFreeT f) | ||
818 | case x of | ||
819 | PP.Pure r -> return r | ||
820 | PP.Free p -> do | ||
821 | f' <- p | ||
822 | yield $ T.singleton '\n' | ||
823 | go f' | ||
824 | {-# INLINABLE unlines #-} | ||
825 | |||
826 | {-| Join 'FreeT'-delimited words into a byte stream | ||
827 | |||
828 | Note: This function is purely for demonstration purposes since it assumes a | ||
829 | particular encoding. You should prefer the 'Data.Text.Text' equivalent of | ||
830 | this function from the upcoming @pipes-text@ library. | ||
831 | -} | ||
832 | unwords | ||
833 | :: (Monad m) => FreeT (Producer Text m) m r -> Producer Text m r | ||
834 | unwords = intercalate (yield $ T.pack " ") | ||
835 | {-# INLINABLE unwords #-} | ||
836 | |||
837 | {- $parse | ||
838 | The following parsing utilities are single-byte analogs of the ones found | ||
839 | in @pipes-parse@. | ||
840 | -} | ||
841 | |||
842 | {-| Take bytes until they fail the predicate | ||
843 | |||
844 | Unlike 'takeWhile', this 'PP.unDraw's unused bytes | ||
845 | -} | ||
846 | -- takeWhile' | ||
847 | -- :: (Monad m) | ||
848 | -- => (Char -> Bool) | ||
849 | -- -> Pipe Text Text (StateT (Producer Text m r) m) () | ||
850 | -- takeWhile' = PBP.takeWhile | ||
851 | -- {-# INLINABLE takeWhile' #-} | ||
852 | -- {-# DEPRECATED takeWhile' "Use Pipes.Text.Parse.takeWhile instead" #-} | ||
853 | |||
854 | {- $reexports | ||
855 | "Pipes.Text.Parse" re-exports 'nextByte', 'drawByte', 'unDrawByte', | ||
856 | 'peekByte', and 'isEndOfBytes'. | ||
857 | |||
858 | @Data.Text@ re-exports the 'Text' type. | ||
859 | |||
860 | @Data.Word@ re-exports the 'Char' type. | ||
861 | |||
862 | @Pipes.Parse@ re-exports 'input', 'concat', and 'FreeT' (the type). | ||
863 | -} \ No newline at end of file | ||
@@ -0,0 +1,30 @@ | |||
1 | Copyright (c) 2013, michaelt | ||
2 | |||
3 | All rights reserved. | ||
4 | |||
5 | Redistribution and use in source and binary forms, with or without | ||
6 | modification, are permitted provided that the following conditions are met: | ||
7 | |||
8 | * Redistributions of source code must retain the above copyright | ||
9 | notice, this list of conditions and the following disclaimer. | ||
10 | |||
11 | * Redistributions in binary form must reproduce the above | ||
12 | copyright notice, this list of conditions and the following | ||
13 | disclaimer in the documentation and/or other materials provided | ||
14 | with the distribution. | ||
15 | |||
16 | * Neither the name of michaelt nor the names of other | ||
17 | contributors may be used to endorse or promote products derived | ||
18 | from this software without specific prior written permission. | ||
19 | |||
20 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | ||
21 | "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | ||
22 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | ||
23 | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | ||
24 | OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | ||
25 | SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | ||
26 | LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | ||
27 | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | ||
28 | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
29 | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | ||
30 | OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
diff --git a/Setup.hs b/Setup.hs new file mode 100644 index 0000000..9a994af --- /dev/null +++ b/Setup.hs | |||
@@ -0,0 +1,2 @@ | |||
1 | import Distribution.Simple | ||
2 | main = defaultMain | ||
diff --git a/text-pipes.cabal b/text-pipes.cabal new file mode 100644 index 0000000..1d73a7b --- /dev/null +++ b/text-pipes.cabal | |||
@@ -0,0 +1,33 @@ | |||
1 | -- Initial text-pipes.cabal generated by cabal init. For further | ||
2 | -- documentation, see http://haskell.org/cabal/users-guide/ | ||
3 | |||
4 | name: text-pipes | ||
5 | version: 0.1.0.0 | ||
6 | synopsis: Text pipes. | ||
7 | -- description: | ||
8 | homepage: github.com/michaelt/text-pipes | ||
9 | license: BSD3 | ||
10 | license-file: LICENSE | ||
11 | author: michaelt | ||
12 | maintainer: what_is_it_to_do_anything@yahoo.com | ||
13 | -- copyright: | ||
14 | category: Text | ||
15 | build-type: Simple | ||
16 | -- extra-source-files: | ||
17 | cabal-version: >=1.10 | ||
18 | |||
19 | library | ||
20 | exposed-modules: Data.Text.Pipes | ||
21 | -- other-modules: | ||
22 | other-extensions: RankNTypes | ||
23 | build-depends: base >= 4 && < 5 , | ||
24 | transformers >= 0.2.0.0 && < 0.4, | ||
25 | pipes >=4.0 && < 4.2, | ||
26 | pipes-parse >=2.0 && < 2.1, | ||
27 | pipes-safe, | ||
28 | pipes-bytestring >= 1.0 && < 1.1, | ||
29 | transformers >= 0.3 && < 0.4, | ||
30 | text >=0.11 && < 0.12, | ||
31 | bytestring >=0.10 && < 0.11 | ||
32 | -- hs-source-dirs: | ||
33 | default-language: Haskell2010 \ No newline at end of file | ||