@@ -1,48 +1,29 @@
1−{-# LANGUAGE BangPatterns, CPP, MagicHash, Rank2Types, UnboxedTuples #-}
1+{-# LANGUAGE BangPatterns #-}
2{-# OPTIONS_GHC -fno-warn-orphans #-}
2{-# OPTIONS_GHC -fno-warn-orphans #-}
3−#if __GLASGOW_HASKELL__ >= 702
4−{-# LANGUAGE Trustworthy #-}
6−#if __GLASGOW_HASKELL__ >= 708
7−{-# LANGUAGE TypeFamilies #-}
11-- Module : Data.Text
5-- Module : Data.Text
6+-- Copyright : (c) Tom Harper 2008-2009,
12−-- Copyright : (c) 2009, 2010, 2011, 2012 Bryan O'Sullivan,
7+-- (c) Bryan O'Sullivan 2009,
13−-- (c) 2009 Duncan Coutts,
8+-- (c) Duncan Coutts 2009
14−-- (c) 2008, 2009 Tom Harper
16-- License : BSD-style
10-- License : BSD-style
17−-- Maintainer : bos@serpentine.com
11+-- Maintainer : rtharper@aftereternity.co.uk, bos@serpentine.com,
18-- Stability : experimental
13-- Stability : experimental
19-- Portability : GHC
14-- Portability : GHC
21−-- A time and space-efficient implementation of Unicode text.
16+-- A time and space-efficient implementation of Unicode text using
22−-- Suitable for performance critical use, both in terms of large data
17+-- packed Word16 arrays. Suitable for performance critical use, both
23−-- quantities and high speed.
18+-- in terms of large data quantities and high speed.
25−-- /Note/: Read below the synopsis for important notes on the use of
28-- This module is intended to be imported @qualified@, to avoid name
20-- This module is intended to be imported @qualified@, to avoid name
29-- clashes with "Prelude" functions, e.g.
21-- clashes with "Prelude" functions, e.g.
31-- > import qualified Data.Text as T
23-- > import qualified Data.Text as T
33−-- To use an extended and very rich family of functions for working
34−-- with Unicode text (including normalization, regular expressions,
35−-- non-standard encodings, text breaking, and locales), see
36−-- <http://hackage.haskell.org/package/text-icu the text-icu package >.
38module Data.Text
25module Data.Text
40− -- * Strict vs lazy types
46 -- * Fusion
27 -- * Fusion
47 -- $fusion
28 -- $fusion
@@ -66,7 +47,6 @@ module Data.Text
71 -- * Transformations
51 -- * Transformations
@@ -74,19 +54,6 @@ module Data.Text
74 , intersperse
54 , intersperse
75 , transpose
55 , transpose
79− -- ** Case conversion
91 -- * Folds
58 -- * Folds
@@ -108,13 +75,13 @@ module Data.Text
109 -- ** Scans
76 -- ** Scans
111− , scanl1
78+ -- , scanl1
112− , scanr
79+ -- , scanr
113− , scanr1
80+ -- , scanr1
115 -- ** Accumulating maps
82 -- ** Accumulating maps
116− , mapAccumL
83+ -- , mapAccumL
117− , mapAccumR
84+ -- , mapAccumR
119 -- ** Generation and unfolding
86 -- ** Generation and unfolding
120 , replicate
87 , replicate
@@ -125,348 +92,173 @@ module Data.Text
126 -- ** Breaking strings
93 -- ** Breaking strings
131 , takeWhile
96 , takeWhile
133 , dropWhile
97 , dropWhile
139− , splitAt
98+ -- , splitAt
140− , breakOn
99+ -- , span
142− , break
100+ -- , break
144− , group
101+ -- , group
145− , groupBy
102+ -- , groupBy
149 -- ** Breaking into many substrings
106 -- ** Breaking into many substrings
150− -- $split
107+ -- , split
151− , splitOn
108+ -- , splitWith
152− , split
109+ -- , breakSubstring
155 -- ** Breaking into lines and words
111 -- ** Breaking into lines and words
159 , unlines
114 , unlines
160 , unwords
115 , unwords
162 -- * Predicates
117 -- * Predicates
163− , isPrefixOf
118+ -- , isPrefixOf
164− , isSuffixOf
119+ -- , isSuffixOf
165− , isInfixOf
120+ -- , isInfixOf
172 -- * Searching
122 -- * Searching
176− , partition
126+ -- , partition
178 -- , findSubstring
128 -- , findSubstring
179−
129+ -- , findSubstrings
180 -- * Indexing
131 -- * Indexing
183 , findIndex
133 , findIndex
184− , count
137+ -- , count
186− -- * Zipping
139+ -- * Zipping and unzipping
188 , zipWith
140 , zipWith
190− -- -* Ordered text
142+ -- * Ordered ByteStrings
191− -- , sort
143+ , -- sort
193− -- * Low level operations
198−import Prelude (Char, Bool(..), Int, Maybe(..), String,
146+import Prelude (Char, Bool, Functor(..), Int, Maybe(..), String,
199− Eq(..), Ord(..), Ordering(..), (++),
147+ Eq, (==), (++), error,
200− Read(..),
149+ Read, readsPrec,
201− (&&), (||), (+), (-), (.), ($), ($!), (>>),
150+ (&&), (||), (+), (-), (<), (>), (<=), (>=), (.),
202− not, return, otherwise, quot)
151+ return, otherwise)
203−#if defined(HAVE_DEEPSEQ)
204−import Control.DeepSeq (NFData(rnf))
207−import Control.Exception (assert)
209import Data.Char (isSpace)
152import Data.Char (isSpace)
210−import Data.Data (Data(gfoldl, toConstr, gunfold, dataTypeOf), constrIndex,
211− Constr, mkConstr, DataType, mkDataType, Fixity(Prefix))
212−import Control.Monad (foldM)
213import Control.Monad.ST (ST)
153import Control.Monad.ST (ST)
214import qualified Data.Text.Array as A
154import qualified Data.Text.Array as A
215import qualified Data.List as L
155import qualified Data.List as L
216−import Data.Binary (Binary(get, put))
217import Data.Monoid (Monoid(..))
156import Data.Monoid (Monoid(..))
218−#if MIN_VERSION_base(4,9,0)
219−import Data.Semigroup (Semigroup(..))
157+import Data.Word (Word16)
221import Data.String (IsString(..))
158import Data.String (IsString(..))
222−import qualified Data.Text.Internal.Fusion as S
223−import qualified Data.Text.Internal.Fusion.Common as S
224−import Data.Text.Encoding (decodeUtf8', encodeUtf8)
225−import Data.Text.Internal.Fusion (stream, reverseStream, unstream)
226−import Data.Text.Internal.Private (span_)
227−import Data.Text.Internal (Text(..), empty, firstf, mul, safe, text)
228−import Data.Text.Show (singleton, unpack, unpackCString#)
229−import qualified Prelude as P
230−import Data.Text.Unsafe (Iter(..), iter, iter_, lengthWord16, reverseIter,
231− reverseIter_, unsafeHead, unsafeTail)
232−import Data.Text.Internal.Unsafe.Char (unsafeChr)
233−import qualified Data.Text.Internal.Functions as F
234−import qualified Data.Text.Internal.Encoding.Utf16 as U16
235−import Data.Text.Internal.Search (indices)
236−#if defined(__HADDOCK__)
237−import Data.ByteString (ByteString)
238−import qualified Data.Text.Lazy as L
239−import Data.Int (Int64)
241−import GHC.Base (eqInt, neInt, gtInt, geInt, ltInt, leInt)
242−#if __GLASGOW_HASKELL__ >= 708
243−import qualified GHC.Exts as Exts
245−#if MIN_VERSION_base(4,7,0)
246−import Text.Printf (PrintfArg, formatArg, formatString)
251−-- This package provides both strict and lazy 'Text' types. The
252−-- strict type is provided by the "Data.Text" module, while the lazy
253−-- type is provided by the "Data.Text.Lazy" module. Internally, the
254−-- lazy @Text@ type consists of a list of strict chunks.
256−-- The strict 'Text' type requires that an entire string fit into
257−-- memory at once. The lazy 'Data.Text.Lazy.Text' type is capable of
258−-- streaming strings that are larger than memory using a small memory
259−-- footprint. In many cases, the overhead of chunked streaming makes
260−-- the lazy 'Data.Text.Lazy.Text' type slower than its strict
261−-- counterpart, but this is not always the case. Sometimes, the time
262−-- complexity of a function in one module may be different from the
263−-- other, due to their differing internal structures.
265−-- Each module provides an almost identical API, with the main
266−-- difference being that the strict module uses 'Int' values for
267−-- lengths and counts, while the lazy module uses 'Data.Int.Int64'
270−-- $replacement
160+import qualified Data.Text.Fusion as S
271−--
161+import Data.Text.Fusion (Stream(..), Step(..), stream, unstream)
272−-- A 'Text' value is a sequence of Unicode scalar values, as defined
162+import Data.Text.Internal (Text(..), empty)
273−-- in
163+import qualified Prelude as P
274−-- <http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#page=35 §3.9, definition D76 of the Unicode 5.2 standard >.
164+import Data.Text.UnsafeChar (unsafeChr)
275−-- As such, a 'Text' cannot contain values in the range U+D800 to
165+import qualified Data.Text.Utf16 as U16
276−-- U+DFFF inclusive. Haskell implementations admit all Unicode code
278−-- (<http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#page=13 §3.4, definition D10 >)
279−-- as 'Char' values, including code points from this invalid range.
280−-- This means that there are some 'Char' values that are not valid
281−-- Unicode scalar values, and the functions in this module must handle
284−-- Within this module, many functions construct a 'Text' from one or
285−-- more 'Char' values. Those functions will substitute 'Char' values
286−-- that are not valid Unicode scalar values with the replacement
287−-- character \"�\" (U+FFFD). Functions that perform this
288−-- inspection and replacement are documented with the phrase
289−-- \"Performs replacement on invalid scalar values\".
291−-- (One reason for this policy of replacement is that internally, a
292−-- 'Text' value is represented as packed UTF-16 data. Values in the
293−-- range U+D800 through U+DFFF are used by UTF-16 to denote surrogate
294−-- code points, and so cannot be represented. The functions replace
295−-- invalid scalar values, instead of dropping them, as a security
296−-- measure. For details, see
297−-- <http://unicode.org/reports/tr36/#Deletion_of_Noncharacters Unicode Technical Report 36, §3.5 >.)
299-- $fusion
167-- $fusion
301−-- Most of the functions in this module are subject to /fusion/,
169+-- Most of the functions in this module are subject to /array fusion/,
302−-- meaning that a pipeline of such functions will usually allocate at
170+-- meaning that a pipeline of functions will usually allocate at most
303−-- most one 'Text' value.
171+-- one 'Text' value.
305−-- As an example, consider the following pipeline:
307−-- > import Data.Text as T
308−-- > import Data.Text.Encoding as E
309−-- > import Data.ByteString (ByteString)
311−-- > countChars :: ByteString -> Int
312−-- > countChars = T.length . T.toUpper . E.decodeUtf8
314−-- From the type signatures involved, this looks like it should
315−-- allocate one 'Data.ByteString.ByteString' value, and two 'Text'
316−-- values. However, when a module is compiled with optimisation
317−-- enabled under GHC, the two intermediate 'Text' values will be
318−-- optimised away, and the function will be compiled down to a single
319−-- loop over the source 'Data.ByteString.ByteString'.
321−-- Functions that can be fused by the compiler are documented with the
322−-- phrase \"Subject to fusion\".
324instance Eq Text where
173instance Eq Text where
325− Text arrA offA lenA == Text arrB offB lenB
174+ t1 == t2 = (stream t1) `S.eq` (stream t2)
326− | lenA == lenB = A.equal arrA offA arrB offB lenA
330−instance Ord Text where
176+instance Show Text where
331− compare = compareText
177+ showsPrec p ps r = showsPrec p (unpack ps) r
333instance Read Text where
179instance Read Text where
334 readsPrec p str = [(pack x,y) | (x,y) <- readsPrec p str]
180 readsPrec p str = [(pack x,y) | (x,y) <- readsPrec p str]
336−#if MIN_VERSION_base(4,9,0)
337−-- Semigroup orphan instances for older GHCs are provided by
338−-- 'semigroups` package
340−instance Semigroup Text where
344instance Monoid Text where
182instance Monoid Text where
345 mempty = empty
183 mempty = empty
346−#if MIN_VERSION_base(4,9,0)
347− mappend = (<>) -- future-proof definition
349 mappend = append
184 mappend = append
351 mconcat = concat
185 mconcat = concat
353instance IsString Text where
187instance IsString Text where
354 fromString = pack
188 fromString = pack
356−#if __GLASGOW_HASKELL__ >= 708
357−instance Exts.IsList Text where
358− type Item Text = Char
363−#if defined(HAVE_DEEPSEQ)
364−instance NFData Text where rnf !_ = ()
367−instance Binary Text where
368− put t = put (encodeUtf8 t)
371− case decodeUtf8' bs of
372− P.Left exn -> P.fail (P.show exn)
373− P.Right a -> P.return a
375−-- | This instance preserves data abstraction at the cost of inefficiency.
376−-- We omit reflection services for the sake of data abstraction.
378−-- This instance was created by copying the updated behavior of
379−-- @"Data.Set".@'Data.Set.Set' and @"Data.Map".@'Data.Map.Map'. If you
380−-- feel a mistake has been made, please feel free to submit
383−-- The original discussion is archived here:
384−-- <http://groups.google.com/group/haskell-cafe/browse_thread/thread/b5bbb1b28a7e525d/0639d46852575b93 could we get a Data instance for Data.Text.Text? >
386−-- The followup discussion that changed the behavior of 'Data.Set.Set'
387−-- and 'Data.Map.Map' is archived here:
388−-- <http://markmail.org/message/trovdc6zkphyi3cr#query:+page:1+mid:a46der3iacwjcf6n+state:results Proposal: Allow gunfold for Data.Map, ... >
390−instance Data Text where
391− gfoldl f z txt = z pack `f` (unpack txt)
392− toConstr _ = packConstr
393− gunfold k z c = case constrIndex c of
395− _ -> P.error "gunfold"
396− dataTypeOf _ = textDataType
398−#if MIN_VERSION_base(4,7,0)
399−-- | Only defined for @base-4.7.0.0@ and later
400−instance PrintfArg Text where
401− formatArg txt = formatString $ unpack txt
405−packConstr = mkConstr textDataType "pack" [] Prefix
407−textDataType :: DataType
408−textDataType = mkDataType "Data.Text.Text" [packConstr]
410−-- | /O(n)/ Compare two 'Text' values lexicographically.
411−compareText :: Text -> Text -> Ordering
412−compareText ta@(Text _arrA _offA lenA) tb@(Text _arrB _offB lenB)
413− | lenA == 0 && lenB == 0 = EQ
414− | otherwise = go 0 0
417− | i >= lenA || j >= lenB = compare lenA lenB
420− | otherwise = go (i+di) (j+dj)
421− where Iter a di = iter ta i
422− Iter b dj = iter tb j
424-- -----------------------------------------------------------------------------
190-- -----------------------------------------------------------------------------
425-- * Conversion to/from 'Text'
191-- * Conversion to/from 'Text'
427−-- | /O(n)/ Convert a 'String' into a 'Text'. Subject to
193+-- | /O(n)/ Convert a 'String' into a 'Text'.
428−-- fusion. Performs replacement on invalid scalar values.
194+--
195+-- This function is subject to array fusion.
429pack :: String -> Text
196pack :: String -> Text
430−pack = unstream . S.map safe . S.streamList
197+pack str = (unstream (stream_list str))
199+ stream_list s0 = S.Stream next s0 (P.length s0) -- total guess
202+ next (x:xs) = S.Yield x xs
431{-# INLINE [1] pack #-}
203{-# INLINE [1] pack #-}
204+-- TODO: Has to do validation! -- No, it doesn't, the
206+-- | /O(n)/ Convert a Text into a String.
207+-- Subject to array fusion.
208+unpack :: Text -> String
209+unpack txt = (unstream_list (stream txt))
211+ unstream_list (S.Stream next s0 _len) = unfold s0
213+ unfold !s = case next s of
215+ S.Skip s' -> unfold s'
216+ S.Yield x s' -> x : unfold s'
217+{-# INLINE [1] unpack #-}
219+-- | /O(1)/ Convert a character into a Text.
220+-- Subject to array fusion.
221+singleton :: Char -> Text
222+singleton c = unstream (Stream next (c:[]) 1)
225+ next (k:ks) = Yield k ks
227+{-# INLINE [1] singleton #-}
433-- -----------------------------------------------------------------------------
229-- -----------------------------------------------------------------------------
434-- * Basic functions
230-- * Basic functions
436-- | /O(n)/ Adds a character to the front of a 'Text'. This function
232-- | /O(n)/ Adds a character to the front of a 'Text'. This function
437-- is more costly than its 'List' counterpart because it requires
233-- is more costly than its 'List' counterpart because it requires
438−-- copying a new array. Subject to fusion. Performs replacement on
234+-- copying a new array. Subject to array fusion.
439−-- invalid scalar values.
440cons :: Char -> Text -> Text
235cons :: Char -> Text -> Text
441−cons c t = unstream (S.cons (safe c) (stream t))
236+cons c t = unstream (S.cons c (stream t))
442{-# INLINE cons #-}
237{-# INLINE cons #-}
446-- | /O(n)/ Adds a character to the end of a 'Text'. This copies the
239-- | /O(n)/ Adds a character to the end of a 'Text'. This copies the
447−-- entire array in the process, unless fused. Subject to fusion.
240+-- entire array in the process. Subject to array fusion.
448−-- Performs replacement on invalid scalar values.
449snoc :: Text -> Char -> Text
241snoc :: Text -> Char -> Text
450−snoc t c = unstream (S.snoc (stream t) (safe c))
242+snoc t c = unstream (S.snoc (stream t) c)
451{-# INLINE snoc #-}
243{-# INLINE snoc #-}
453-- | /O(n)/ Appends one 'Text' to the other by copying both of them
245-- | /O(n)/ Appends one 'Text' to the other by copying both of them
454−-- into a new 'Text'. Subject to fusion.
246+-- into a new 'Text'. Subject to array fusion.
455append :: Text -> Text -> Text
247append :: Text -> Text -> Text
456−append a@(Text arr1 off1 len1) b@(Text arr2 off2 len2)
248+append (Text arr1 off1 len1) (Text arr2 off2 len2) = Text (A.run x) 0 len
459− | len > 0 = Text (A.run x) 0 len
460− | otherwise = overflowError "append"
462 len = len1+len2
250 len = len1+len2
463− x :: ST s (A.MArray s)
465− arr <- A.new len
252+ arr <- A.unsafeNew len :: ST s (A.MArray s Word16)
466− A.copyI arr 0 arr1 off1 len1
253+ copy arr1 off1 (len1+off1) arr 0
467− A.copyI arr len1 arr2 off2 len
254+ copy arr2 off2 (len2+off2) arr len1
468 return arr
255 return arr
257+ copy arr i max arr' j
258+ | i >= max = return ()
259+ | otherwise = do A.unsafeWrite arr' j (arr `A.unsafeIndex` i)
260+ copy arr (i+1) max arr' (j+1)
469−{-# NOINLINE append #-}
261+{-# INLINE append #-}
472"TEXT append -> fused" [~1] forall t1 t2.
264"TEXT append -> fused" [~1] forall t1 t2.
@@ -476,33 +268,46 @@ append a@(Text arr1 off1 len1) b@(Text arr2 off2 len2)
478-- | /O(1)/ Returns the first character of a 'Text', which must be
270-- | /O(1)/ Returns the first character of a 'Text', which must be
479−-- non-empty. Subject to fusion.
271+-- non-empty. Subject to array fusion.
480head :: Text -> Char
272head :: Text -> Char
481head t = S.head (stream t)
273head t = S.head (stream t)
482{-# INLINE head #-}
274{-# INLINE head #-}
484-- | /O(1)/ Returns the first character and rest of a 'Text', or
276-- | /O(1)/ Returns the first character and rest of a 'Text', or
485−-- 'Nothing' if empty. Subject to fusion.
277+-- 'Nothing' if empty. Subject to array fusion.
486uncons :: Text -> Maybe (Char, Text)
278uncons :: Text -> Maybe (Char, Text)
487−uncons t@(Text arr off len)
279+uncons (Text arr off len)
488 | len <= 0 = Nothing
280 | len <= 0 = Nothing
489− | otherwise = Just $ let !(Iter c d) = iter t 0
281+ | otherwise = Just (c, Text arr (off+k) (len-k))
490− in (c, text arr (off+d) (len-d))
282+ where c | single = unsafeChr m
283+ | otherwise = U16.chr2 m n
286+ single = m < 0xD800 || m > 0xDBFF
287+ m = A.unsafeIndex arr off
288+ n = A.unsafeIndex arr (off+1)
491−{-# INLINE [1] uncons #-}
289+{-# INLINE uncons #-}
493−-- | Lifted from Control.Arrow and specialized.
494second :: (b -> c) -> (a,b) -> (a,c)
291second :: (b -> c) -> (a,b) -> (a,c)
495second f (a, b) = (a, f b)
292second f (a, b) = (a, f b)
295+"TEXT uncons -> fused" [~1] forall t.
296+ uncons t = fmap (second unstream) (S.uncons (stream t))
297+"TEXT uncons -> unfused" [1] forall t.
298+ fmap (second unstream) (S.uncons (stream t)) = uncons t
497-- | /O(1)/ Returns the last character of a 'Text', which must be
301-- | /O(1)/ Returns the last character of a 'Text', which must be
498−-- non-empty. Subject to fusion.
302+-- non-empty. Subject to array fusion.
499last :: Text -> Char
303last :: Text -> Char
500last (Text arr off len)
304last (Text arr off len)
501− | len <= 0 = emptyError "last"
305+ | len <= 0 = errorEmptyList "last"
502 | n < 0xDC00 || n > 0xDFFF = unsafeChr n
306 | n < 0xDC00 || n > 0xDFFF = unsafeChr n
503 | otherwise = U16.chr2 n0 n
307 | otherwise = U16.chr2 n0 n
504− where n = A.unsafeIndex arr (off+len-1)
309+ n = A.unsafeIndex arr (off+len-1)
505− n0 = A.unsafeIndex arr (off+len-2)
310+ n0 = A.unsafeIndex arr (off+len-2)
506{-# INLINE [1] last #-}
311{-# INLINE [1] last #-}
@@ -512,28 +317,26 @@ last (Text arr off len)
512 S.last (stream t) = last t
317 S.last (stream t) = last t
515-- | /O(1)/ Returns all characters after the head of a 'Text', which
321-- | /O(1)/ Returns all characters after the head of a 'Text', which
516−-- must be non-empty. Subject to fusion.
322+-- must be non-empty. Subject to array fusion.
517tail :: Text -> Text
323tail :: Text -> Text
518−tail t@(Text arr off len)
324+tail (Text arr off len)
519− | len <= 0 = emptyError "tail"
325+ | len <= 0 = errorEmptyList "tail"
326+ | n >= 0xD800 && n <= 0xDBFF = Text arr (off+2) (len-2)
520− | otherwise = text arr (off+d) (len-d)
327+ | otherwise = Text arr (off+1) (len-1)
521− where d = iter_ t 0
328+ where
329+ n = A.unsafeIndex arr off
522{-# INLINE [1] tail #-}
330{-# INLINE [1] tail #-}
525−"TEXT tail -> fused" [~1] forall t.
526− tail t = unstream (S.tail (stream t))
527−"TEXT tail -> unfused" [1] forall t.
528− unstream (S.tail (stream t)) = tail t
531-- | /O(1)/ Returns all but the last character of a 'Text', which must
334-- | /O(1)/ Returns all but the last character of a 'Text', which must
532−-- be non-empty. Subject to fusion.
335+-- be non-empty. Subject to array fusion.
533init :: Text -> Text
336init :: Text -> Text
534−init (Text arr off len) | len <= 0 = emptyError "init"
337+init (Text arr off len) | len <= 0 = errorEmptyList "init"
535− | n >= 0xDC00 && n <= 0xDFFF = text arr off (len-2)
338+ | n >= 0xDC00 && n <= 0xDFFF = Text arr off (len-2)
536− | otherwise = text arr off (len-1)
339+ | otherwise = Text arr off (len-1)
538 n = A.unsafeIndex arr (off+len-1)
341 n = A.unsafeIndex arr (off+len-1)
539{-# INLINE [1] init #-}
342{-# INLINE [1] init #-}
@@ -545,304 +348,47 @@ init (Text arr off len) | len <= 0 = emptyError "init"
545 unstream (S.init (stream t)) = init t
348 unstream (S.init (stream t)) = init t
548−-- | /O(1)/ Tests whether a 'Text' is empty or not. Subject to
351+-- | /O(1)/ Tests whether a 'Text' is empty or not. Subject to array
549-- fusion.
352-- fusion.
550null :: Text -> Bool
353null :: Text -> Bool
551−null (Text _arr _off len) =
556−{-# INLINE [1] null #-}
559−"TEXT null -> fused" [~1] forall t.
560− null t = S.null (stream t)
354+null t = S.null (stream t)
561−"TEXT null -> unfused" [1] forall t.
562− S.null (stream t) = null t
565−-- | /O(1)/ Tests whether a 'Text' contains exactly one character.
566−-- Subject to fusion.
567−isSingleton :: Text -> Bool
568−isSingleton = S.isSingleton . stream
569−{-# INLINE isSingleton #-}
355+{-# INLINE null #-}
571-- | /O(n)/ Returns the number of characters in a 'Text'.
357-- | /O(n)/ Returns the number of characters in a 'Text'.
572−-- Subject to fusion.
358+-- Subject to array fusion.
573length :: Text -> Int
359length :: Text -> Int
574length t = S.length (stream t)
360length t = S.length (stream t)
575−{-# INLINE [0] length #-}
361+{-# INLINE length #-}
576−-- length needs to be phased after the compareN/length rules otherwise
577−-- it may inline before the rules have an opportunity to fire.
579−-- | /O(n)/ Compare the count of characters in a 'Text' to a number.
580−-- Subject to fusion.
582−-- This function gives the same answer as comparing against the result
583−-- of 'length', but can short circuit if the count of characters is
584−-- greater than the number, and hence be more efficient.
585−compareLength :: Text -> Int -> Ordering
586−compareLength t n = S.compareLengthI (stream t) n
587−{-# INLINE [1] compareLength #-}
590−"TEXT compareN/length -> compareLength" [~1] forall t n.
591− compare (length t) n = compareLength t n
595−"TEXT ==N/length -> compareLength/==EQ" [~1] forall t n.
596− eqInt (length t) n = compareLength t n == EQ
600−"TEXT /=N/length -> compareLength//=EQ" [~1] forall t n.
601− neInt (length t) n = compareLength t n /= EQ
605−"TEXT <N/length -> compareLength/==LT" [~1] forall t n.
606− ltInt (length t) n = compareLength t n == LT
610−"TEXT <=N/length -> compareLength//=GT" [~1] forall t n.
611− leInt (length t) n = compareLength t n /= GT
615−"TEXT >N/length -> compareLength/==GT" [~1] forall t n.
616− gtInt (length t) n = compareLength t n == GT
620−"TEXT >=N/length -> compareLength//=LT" [~1] forall t n.
621− geInt (length t) n = compareLength t n /= LT
624-- -----------------------------------------------------------------------------
363-- -----------------------------------------------------------------------------
625-- * Transformations
364-- * Transformations
626−-- | /O(n)/ 'map' @f@ @t@ is the 'Text' obtained by applying @f@ to
365+-- | /O(n)/ 'map' @f @xs is the 'Text' obtained by applying @f@ to
627−-- each element of @t@. Subject to fusion. Performs replacement on
366+-- each element of @xs@. Subject to array fusion.
628−-- invalid scalar values.
629map :: (Char -> Char) -> Text -> Text
367map :: (Char -> Char) -> Text -> Text
630−map f t = unstream (S.map (safe . f) (stream t))
368+map f t = unstream (S.map f (stream t))
631{-# INLINE [1] map #-}
369{-# INLINE [1] map #-}
633-- | /O(n)/ The 'intercalate' function takes a 'Text' and a list of
371-- | /O(n)/ The 'intercalate' function takes a 'Text' and a list of
634-- 'Text's and concatenates the list after interspersing the first
372-- 'Text's and concatenates the list after interspersing the first
635-- argument between each element of the list.
373-- argument between each element of the list.
636intercalate :: Text -> [Text] -> Text
374intercalate :: Text -> [Text] -> Text
637−intercalate t = concat . (F.intersperse t)
375+intercalate t ts = unstream (S.intercalate (stream t) (L.map stream ts))
638{-# INLINE intercalate #-}
376{-# INLINE intercalate #-}
640-- | /O(n)/ The 'intersperse' function takes a character and places it
378-- | /O(n)/ The 'intersperse' function takes a character and places it
641−-- between the characters of a 'Text'. Subject to fusion. Performs
379+-- between the characters of a 'Text'. Subject to array fusion.
642−-- replacement on invalid scalar values.
643intersperse :: Char -> Text -> Text
380intersperse :: Char -> Text -> Text
644−intersperse c t = unstream (S.intersperse (safe c) (stream t))
381+intersperse c t = unstream (S.intersperse c (stream t))
645{-# INLINE intersperse #-}
382{-# INLINE intersperse #-}
647−-- | /O(n)/ Reverse the characters of a string. Subject to fusion.
384+-- | /O(n)/ Reverse the characters of a string. Subject to array fusion.
648reverse :: Text -> Text
385reverse :: Text -> Text
649reverse t = S.reverse (stream t)
386reverse t = S.reverse (stream t)
650{-# INLINE reverse #-}
387{-# INLINE reverse #-}
652−-- | /O(m+n)/ Replace every non-overlapping occurrence of @needle@ in
653−-- @haystack@ with @replacement@.
655−-- This function behaves as though it was defined as follows:
658−-- replace needle replacement haystack =
659−-- 'intercalate' replacement ('splitOn' needle haystack)
662−-- As this suggests, each occurrence is replaced exactly once. So if
663−-- @needle@ occurs in @replacement@, that occurrence will /not/ itself
664−-- be replaced recursively:
666−-- > replace "oo" "foo" "oo" == "foo"
668−-- In cases where several instances of @needle@ overlap, only the
669−-- first one will be replaced:
671−-- > replace "ofo" "bar" "ofofo" == "barfo"
673−-- In (unlikely) bad cases, this function's time complexity degrades
676− -- ^ @needle@ to search for. If this string is empty, an
677− -- error will occur.
679− -- ^ @replacement@ to replace @needle@ with.
681− -- ^ @haystack@ in which to search.
683−replace needle@(Text _ _ neeLen)
684− (Text repArr repOff repLen)
685− haystack@(Text hayArr hayOff hayLen)
686− | neeLen == 0 = emptyError "replace"
687− | L.null ixs = haystack
688− | len > 0 = Text (A.run x) 0 len
691− ixs = indices needle haystack
692− len = hayLen - (neeLen - repLen) `mul` L.length ixs
693− x :: ST s (A.MArray s)
696− let loop (i:is) o d = do
699− A.copyI marr d hayArr (hayOff+o) d0
700− A.copyI marr d0 repArr repOff d1
701− loop is (i + neeLen) d1
702− loop [] o d = A.copyI marr d hayArr (hayOff+o) len
706−-- ----------------------------------------------------------------------------
707−-- ** Case conversions (folds)
711−-- When case converting 'Text' values, do not use combinators like
712−-- @map toUpper@ to case convert each character of a string
713−-- individually, as this gives incorrect results according to the
714−-- rules of some writing systems. The whole-string case conversion
715−-- functions from this module, such as @toUpper@, obey the correct
716−-- case conversion rules. As a result, these functions may map one
717−-- input character to two or three output characters. For examples,
718−-- see the documentation of each function.
720−-- /Note/: In some languages, case conversion is a locale- and
721−-- context-dependent operation. The case conversion functions in this
722−-- module are /not/ locale sensitive. Programs that require locale
723−-- sensitivity should use appropriate versions of the
724−-- <http://hackage.haskell.org/package/text-icu-0.6.3.7/docs/Data-Text-ICU.html#g:4 case mapping functions from the text-icu package >.
726−-- | /O(n)/ Convert a string to folded case. Subject to fusion.
728−-- This function is mainly useful for performing caseless (also known
729−-- as case insensitive) string comparisons.
731−-- A string @x@ is a caseless match for a string @y@ if and only if:
733−-- @toCaseFold x == toCaseFold y@
735−-- The result string may be longer than the input string, and may
736−-- differ from applying 'toLower' to the input string. For instance,
737−-- the Armenian small ligature \"ﬓ\" (men now, U+FB13) is case
738−-- folded to the sequence \"մ\" (men, U+0574) followed by
739−-- \"ն\" (now, U+0576), while the Greek \"µ\" (micro sign,
740−-- U+00B5) is case folded to \"μ\" (small letter mu, U+03BC)
741−-- instead of itself.
742−toCaseFold :: Text -> Text
743−toCaseFold t = unstream (S.toCaseFold (stream t))
744−{-# INLINE toCaseFold #-}
746−-- | /O(n)/ Convert a string to lower case, using simple case
747−-- conversion. Subject to fusion.
749−-- The result string may be longer than the input string. For
750−-- instance, \"İ\" (Latin capital letter I with dot above,
751−-- U+0130) maps to the sequence \"i\" (Latin small letter i, U+0069)
752−-- followed by \" ̇\" (combining dot above, U+0307).
753−toLower :: Text -> Text
754−toLower t = unstream (S.toLower (stream t))
755−{-# INLINE toLower #-}
757−-- | /O(n)/ Convert a string to upper case, using simple case
758−-- conversion. Subject to fusion.
760−-- The result string may be longer than the input string. For
761−-- instance, the German \"ß\" (eszett, U+00DF) maps to the
762−-- two-letter sequence \"SS\".
763−toUpper :: Text -> Text
764−toUpper t = unstream (S.toUpper (stream t))
765−{-# INLINE toUpper #-}
767−-- | /O(n)/ Convert a string to title case, using simple case
768−-- conversion. Subject to fusion.
770−-- The first letter of the input is converted to title case, as is
771−-- every subsequent letter that immediately follows a non-letter.
772−-- Every letter that immediately follows another letter is converted
775−-- The result string may be longer than the input string. For example,
776−-- the Latin small ligature fl (U+FB02) is converted to the
777−-- sequence Latin capital letter F (U+0046) followed by Latin small
778−-- letter l (U+006C).
780−-- /Note/: this function does not take language or culture specific
781−-- rules into account. For instance, in English, different style
782−-- guides disagree on whether the book name \"The Hill of the Red
783−-- Fox\" is correctly title cased—but this function will
784−-- capitalize /every/ word.
785−toTitle :: Text -> Text
786−toTitle t = unstream (S.toTitle (stream t))
787−{-# INLINE toTitle #-}
789−-- | /O(n)/ Left-justify a string to the given length, using the
790−-- specified fill character on the right. Subject to fusion.
791−-- Performs replacement on invalid scalar values.
795−-- > justifyLeft 7 'x' "foo" == "fooxxxx"
796−-- > justifyLeft 3 'x' "foobar" == "foobar"
797−justifyLeft :: Int -> Char -> Text -> Text
800− | otherwise = t `append` replicateChar (k-len) c
801− where len = length t
802−{-# INLINE [1] justifyLeft #-}
805−"TEXT justifyLeft -> fused" [~1] forall k c t.
806− justifyLeft k c t = unstream (S.justifyLeftI k c (stream t))
807−"TEXT justifyLeft -> unfused" [1] forall k c t.
808− unstream (S.justifyLeftI k c (stream t)) = justifyLeft k c t
811−-- | /O(n)/ Right-justify a string to the given length, using the
812−-- specified fill character on the left. Performs replacement on
813−-- invalid scalar values.
817−-- > justifyRight 7 'x' "bar" == "xxxxbar"
818−-- > justifyRight 3 'x' "foobar" == "foobar"
819−justifyRight :: Int -> Char -> Text -> Text
822− | otherwise = replicateChar (k-len) c `append` t
823− where len = length t
824−{-# INLINE justifyRight #-}
826−-- | /O(n)/ Center a string to the given length, using the specified
827−-- fill character on either side. Performs replacement on invalid
832−-- > center 8 'x' "HS" = "xxxHSxxx"
833−center :: Int -> Char -> Text -> Text
836− | otherwise = replicateChar l c `append` t `append` replicateChar r c
837− where len = length t
841−{-# INLINE center #-}
843-- | /O(n)/ The 'transpose' function transposes the rows and columns
389-- | /O(n)/ The 'transpose' function transposes the rows and columns
844-- of its 'Text' argument. Note that this function uses 'pack',
390-- of its 'Text' argument. Note that this function uses 'pack',
845−-- 'unpack', and the list version of transpose, and is thus not very
391+-- 'unpack', and the 'List' version of transpose and is thus not very
846-- efficient.
392-- efficient.
847transpose :: [Text] -> [Text]
393transpose :: [Text] -> [Text]
848transpose ts = P.map pack (L.transpose (P.map unpack ts))
394transpose ts = P.map pack (L.transpose (P.map unpack ts))
@@ -850,40 +396,43 @@ transpose ts = P.map pack (L.transpose (P.map unpack ts))
850-- -----------------------------------------------------------------------------
396-- -----------------------------------------------------------------------------
851-- * Reducing 'Text's (folds)
397-- * Reducing 'Text's (folds)
853−-- | /O(n)/ 'foldl', applied to a binary operator, a starting value
399+-- | 'foldl', applied to a binary operator, a starting value
854-- (typically the left-identity of the operator), and a 'Text',
400-- (typically the left-identity of the operator), and a 'Text',
855-- reduces the 'Text' using the binary operator, from left to right.
401-- reduces the 'Text' using the binary operator, from left to right.
856−-- Subject to fusion.
402+-- Subject to array fusion.
857−foldl :: (a -> Char -> a) -> a -> Text -> a
403+foldl :: (b -> Char -> b) -> b -> Text -> b
858foldl f z t = S.foldl f z (stream t)
404foldl f z t = S.foldl f z (stream t)
859{-# INLINE foldl #-}
405{-# INLINE foldl #-}
861−-- | /O(n)/ A strict version of 'foldl'. Subject to fusion.
407+-- | A strict version of 'foldl'.
408+-- Subject to array fusion.
862−foldl' :: (a -> Char -> a) -> a -> Text -> a
409+foldl' :: (b -> Char -> b) -> b -> Text -> b
863foldl' f z t = S.foldl' f z (stream t)
410foldl' f z t = S.foldl' f z (stream t)
864{-# INLINE foldl' #-}
411{-# INLINE foldl' #-}
866−-- | /O(n)/ A variant of 'foldl' that has no starting value argument,
413+-- | A variant of 'foldl' that has no starting value argument, and
867−-- and thus must be applied to a non-empty 'Text'. Subject to fusion.
414+-- thus must be applied to a non-empty 'Text'. Subject to array
868foldl1 :: (Char -> Char -> Char) -> Text -> Char
416foldl1 :: (Char -> Char -> Char) -> Text -> Char
869foldl1 f t = S.foldl1 f (stream t)
417foldl1 f t = S.foldl1 f (stream t)
870{-# INLINE foldl1 #-}
418{-# INLINE foldl1 #-}
872−-- | /O(n)/ A strict version of 'foldl1'. Subject to fusion.
420+-- | A strict version of 'foldl1'.
421+-- Subject to array fusion.
873foldl1' :: (Char -> Char -> Char) -> Text -> Char
422foldl1' :: (Char -> Char -> Char) -> Text -> Char
874foldl1' f t = S.foldl1' f (stream t)
423foldl1' f t = S.foldl1' f (stream t)
875{-# INLINE foldl1' #-}
424{-# INLINE foldl1' #-}
877−-- | /O(n)/ 'foldr', applied to a binary operator, a starting value
426+-- | 'foldr', applied to a binary operator, a starting value
878-- (typically the right-identity of the operator), and a 'Text',
427-- (typically the right-identity of the operator), and a 'Text',
879-- reduces the 'Text' using the binary operator, from right to left.
428-- reduces the 'Text' using the binary operator, from right to left.
880−-- Subject to fusion.
429+-- Subject to array fusion.
881−foldr :: (Char -> a -> a) -> a -> Text -> a
430+foldr :: (Char -> b -> b) -> b -> Text -> b
882foldr f z t = S.foldr f z (stream t)
431foldr f z t = S.foldr f z (stream t)
883{-# INLINE foldr #-}
432{-# INLINE foldr #-}
885−-- | /O(n)/ A variant of 'foldr' that has no starting value argument,
434+-- | A variant of 'foldr' that has no starting value argument, and
886−-- and thus must be applied to a non-empty 'Text'. Subject to
435+-- thust must be applied to a non-empty 'Text'. Subject to array
887-- fusion.
436-- fusion.
888foldr1 :: (Char -> Char -> Char) -> Text -> Char
437foldr1 :: (Char -> Char -> Char) -> Text -> Char
889foldr1 f t = S.foldr1 f (stream t)
438foldr1 f t = S.foldr1 f (stream t)
@@ -892,48 +441,40 @@ foldr1 f t = S.foldr1 f (stream t)
892-- -----------------------------------------------------------------------------
441-- -----------------------------------------------------------------------------
893-- ** Special folds
442-- ** Special folds
895−-- | /O(n)/ Concatenate a list of 'Text's.
444+-- | /O(n)/ Concatenate a list of 'Text's. Subject to array fusion.
896concat :: [Text] -> Text
445concat :: [Text] -> Text
897−concat ts = case ts' of
446+concat ts = unstream (S.concat (L.map stream ts))
898− [] -> empty
447+{-# INLINE concat #-}
900− _ -> Text (A.run go) 0 len
902− ts' = L.filter (not . null) ts
903− len = sumP "concat" $ L.map lengthWord16 ts'
904− go :: ST s (A.MArray s)
907− let step i (Text a o l) =
908− let !j = i + l in A.copyI arr i a o j >> return j
909− foldM step 0 ts' >> return arr
911−-- | /O(n)/ Map a function over a 'Text' that results in a 'Text', and
449+-- | Map a function over a 'Text' that results in a 'Text', and concatenate the
912−-- concatenate the results.
450+-- results. This function is subject to array fusion.
452+-- Note: if in 'concatMap' @f @xs, @f@ is defined in terms of fusible
453+-- functions, it will also be fusible.
913concatMap :: (Char -> Text) -> Text -> Text
454concatMap :: (Char -> Text) -> Text -> Text
914−concatMap f = concat . foldr ((:) . f) []
455+concatMap f t = unstream (S.concatMap (stream . f) (stream t))
915{-# INLINE concatMap #-}
456{-# INLINE concatMap #-}
917−-- | /O(n)/ 'any' @p@ @t@ determines whether any character in the
458+-- | 'any' @p @xs determines whether any character in the 'Text' @xs@
918−-- 'Text' @t@ satisfies the predicate @p@. Subject to fusion.
459+-- satisifes the predicate @p@. Subject to array fusion.
919any :: (Char -> Bool) -> Text -> Bool
460any :: (Char -> Bool) -> Text -> Bool
920any p t = S.any p (stream t)
461any p t = S.any p (stream t)
921{-# INLINE any #-}
462{-# INLINE any #-}
923−-- | /O(n)/ 'all' @p@ @t@ determines whether all characters in the
464+-- | 'all' @p @xs determines whether all characters in the 'Text' @xs@
924−-- 'Text' @t@ satisfy the predicate @p@. Subject to fusion.
465+-- satisify the predicate @p@. Subject to array fusion.
925all :: (Char -> Bool) -> Text -> Bool
466all :: (Char -> Bool) -> Text -> Bool
926all p t = S.all p (stream t)
467all p t = S.all p (stream t)
927{-# INLINE all #-}
468{-# INLINE all #-}
929-- | /O(n)/ 'maximum' returns the maximum value from a 'Text', which
470-- | /O(n)/ 'maximum' returns the maximum value from a 'Text', which
930−-- must be non-empty. Subject to fusion.
471+-- must be non-empty. Subject to array fusion.
931maximum :: Text -> Char
472maximum :: Text -> Char
932maximum t = S.maximum (stream t)
473maximum t = S.maximum (stream t)
933{-# INLINE maximum #-}
474{-# INLINE maximum #-}
935-- | /O(n)/ 'minimum' returns the minimum value from a 'Text', which
476-- | /O(n)/ 'minimum' returns the minimum value from a 'Text', which
936−-- must be non-empty. Subject to fusion.
477+-- must be non-empty. Subject to array fusion.
937minimum :: Text -> Char
478minimum :: Text -> Char
938minimum t = S.minimum (stream t)
479minimum t = S.minimum (stream t)
939{-# INLINE minimum #-}
480{-# INLINE minimum #-}
@@ -941,141 +482,57 @@ minimum t = S.minimum (stream t)
941-- -----------------------------------------------------------------------------
482-- -----------------------------------------------------------------------------
942-- * Building 'Text's
483-- * Building 'Text's
944−-- | /O(n)/ 'scanl' is similar to 'foldl', but returns a list of
945−-- successive reduced values from the left. Subject to fusion.
946−-- Performs replacement on invalid scalar values.
948−-- > scanl f z [x1, x2, ...] == [z, z `f` x1, (z `f` x1) `f` x2, ...]
952−-- > last (scanl f z xs) == foldl f z xs.
953scanl :: (Char -> Char -> Char) -> Char -> Text -> Text
485scanl :: (Char -> Char -> Char) -> Char -> Text -> Text
954−scanl f z t = unstream (S.scanl g z (stream t))
486+scanl f z t = unstream (S.scanl f z (stream t))
955− where g a b = safe (f a b)
956{-# INLINE scanl #-}
487{-# INLINE scanl #-}
958−-- | /O(n)/ 'scanl1' is a variant of 'scanl' that has no starting
959−-- value argument. Subject to fusion. Performs replacement on
960−-- invalid scalar values.
962−-- > scanl1 f [x1, x2, ...] == [x1, x1 `f` x2, ...]
963−scanl1 :: (Char -> Char -> Char) -> Text -> Text
964−scanl1 f t | null t = empty
965− | otherwise = scanl f (unsafeHead t) (unsafeTail t)
966−{-# INLINE scanl1 #-}
968−-- | /O(n)/ 'scanr' is the right-to-left dual of 'scanl'. Performs
969−-- replacement on invalid scalar values.
971−-- > scanr f v == reverse . scanl (flip f) v . reverse
972−scanr :: (Char -> Char -> Char) -> Char -> Text -> Text
973−scanr f z = S.reverse . S.reverseScanr g z . reverseStream
974− where g a b = safe (f a b)
977−-- | /O(n)/ 'scanr1' is a variant of 'scanr' that has no starting
978−-- value argument. Subject to fusion. Performs replacement on
979−-- invalid scalar values.
980−scanr1 :: (Char -> Char -> Char) -> Text -> Text
981−scanr1 f t | null t = empty
982− | otherwise = scanr f (last t) (init t)
983−{-# INLINE scanr1 #-}
985−-- | /O(n)/ Like a combination of 'map' and 'foldl''. Applies a
986−-- function to each element of a 'Text', passing an accumulating
987−-- parameter from left to right, and returns a final 'Text'. Performs
988−-- replacement on invalid scalar values.
989−mapAccumL :: (a -> Char -> (a,Char)) -> a -> Text -> (a, Text)
990−mapAccumL f z0 = S.mapAccumL g z0 . stream
991− where g a b = second safe (f a b)
992−{-# INLINE mapAccumL #-}
994−-- | The 'mapAccumR' function behaves like a combination of 'map' and
995−-- a strict 'foldr'; it applies a function to each element of a
996−-- 'Text', passing an accumulating parameter from right to left, and
997−-- returning a final value of this accumulator together with the new
999−-- Performs replacement on invalid scalar values.
1000−mapAccumR :: (a -> Char -> (a,Char)) -> a -> Text -> (a, Text)
1001−mapAccumR f z0 = second reverse . S.mapAccumL g z0 . reverseStream
1002− where g a b = second safe (f a b)
1003−{-# INLINE mapAccumR #-}
1005-- -----------------------------------------------------------------------------
489-- -----------------------------------------------------------------------------
1006-- ** Generating and unfolding 'Text's
490-- ** Generating and unfolding 'Text's
1008−-- | /O(n*m)/ 'replicate' @n@ @t@ is a 'Text' consisting of the input
1009−-- @t@ repeated @n@ times.
1010−replicate :: Int -> Text -> Text
1011−replicate n t@(Text a o l)
1012− | n <= 0 || l <= 0 = empty
1014− | isSingleton t = replicateChar n (unsafeHead t)
1015− | otherwise = Text (A.run x) 0 len
1018− x :: ST s (A.MArray s)
1021− let loop !d !i | i >= n = return arr
1022− | otherwise = let m = d + l
1023− in A.copyI arr d a o m >> loop m (i+1)
1025−{-# INLINE [1] replicate #-}
1028−"TEXT replicate/singleton -> replicateChar" [~1] forall n c.
1029− replicate n (singleton c) = replicateChar n c
1032−-- | /O(n)/ 'replicateChar' @n@ @c@ is a 'Text' of length @n@ with @c@ the
1033−-- value of every element. Subject to fusion.
1034−replicateChar :: Int -> Char -> Text
492+replicate :: Int -> Char -> Text
1035−replicateChar n c = unstream (S.replicateCharI n (safe c))
493+replicate n c = unstream (S.replicate n c)
1036−{-# INLINE replicateChar #-}
494+{-# INLINE replicate #-}
1038-- | /O(n)/, where @n@ is the length of the result. The 'unfoldr'
496-- | /O(n)/, where @n@ is the length of the result. The 'unfoldr'
1039-- function is analogous to the List 'L.unfoldr'. 'unfoldr' builds a
497-- function is analogous to the List 'L.unfoldr'. 'unfoldr' builds a
1040-- 'Text' from a seed value. The function takes the element and
498-- 'Text' from a seed value. The function takes the element and
1041-- returns 'Nothing' if it is done producing the 'Text', otherwise
499-- returns 'Nothing' if it is done producing the 'Text', otherwise
1042-- 'Just' @(a,b)@. In this case, @a@ is the next 'Char' in the
500-- 'Just' @(a,b)@. In this case, @a@ is the next 'Char' in the
1043−-- string, and @b@ is the seed value for further production. Subject
501+-- string, and @b@ is the seed value for further production.
1044−-- to fusion. Performs replacement on invalid scalar values.
1045unfoldr :: (a -> Maybe (Char,a)) -> a -> Text
502unfoldr :: (a -> Maybe (Char,a)) -> a -> Text
1046−unfoldr f s = unstream (S.unfoldr (firstf safe . f) s)
503+unfoldr f s = unstream (S.unfoldr f s)
1047{-# INLINE unfoldr #-}
504{-# INLINE unfoldr #-}
1049-- | /O(n)/ Like 'unfoldr', 'unfoldrN' builds a 'Text' from a seed
506-- | /O(n)/ Like 'unfoldr', 'unfoldrN' builds a 'Text' from a seed
1050-- value. However, the length of the result should be limited by the
507-- value. However, the length of the result should be limited by the
1051-- first argument to 'unfoldrN'. This function is more efficient than
508-- first argument to 'unfoldrN'. This function is more efficient than
1052-- 'unfoldr' when the maximum length of the result is known and
509-- 'unfoldr' when the maximum length of the result is known and
1053−-- correct, otherwise its performance is similar to 'unfoldr'. Subject
510+-- correct, otherwise its performance is similar to 'unfoldr'.
1054−-- to fusion. Performs replacement on invalid scalar values.
1055unfoldrN :: Int -> (a -> Maybe (Char,a)) -> a -> Text
511unfoldrN :: Int -> (a -> Maybe (Char,a)) -> a -> Text
1056−unfoldrN n f s = unstream (S.unfoldrN n (firstf safe . f) s)
512+unfoldrN n f s = unstream (S.unfoldrN n f s)
1057{-# INLINE unfoldrN #-}
513{-# INLINE unfoldrN #-}
1059-- -----------------------------------------------------------------------------
515-- -----------------------------------------------------------------------------
1060-- * Substrings
516-- * Substrings
1062−-- | /O(n)/ 'take' @n@, applied to a 'Text', returns the prefix of the
518+-- /O(n) 'take' @n@, applied to a 'Text', returns the prefix of the
1063-- 'Text' of length @n@, or the 'Text' itself if @n@ is greater than
519-- 'Text' of length @n@, or the 'Text' itself if @n@ is greater than
1064−-- the length of the Text. Subject to fusion.
520+-- the length of the Text.
1065take :: Int -> Text -> Text
521take :: Int -> Text -> Text
1066take n t@(Text arr off len)
522take n t@(Text arr off len)
1067 | n <= 0 = empty
523 | n <= 0 = empty
1068 | n >= len = t
524 | n >= len = t
1069− | otherwise = text arr off (iterN n t)
525+ | otherwise = Text arr off (loop off 0)
529+ | i >= end || count >= n = i - off
530+ | c < 0xD800 || c > 0xDBFF = loop (i+1) (count+1)
531+ | otherwise = loop (i+2) (count+1)
533+ c = arr `A.unsafeIndex` i
1070{-# INLINE [1] take #-}
534{-# INLINE [1] take #-}
1072−iterN :: Int -> Text -> Int
1073−iterN n t@(Text _arr _off len) = loop 0 0
1075− | i >= len || cnt >= n = i
1076− | otherwise = loop (i+d) (cnt+1)
1077− where d = iter_ t i
1079{-# RULES
536{-# RULES
1080"TEXT take -> fused" [~1] forall n t.
537"TEXT take -> fused" [~1] forall n t.
1081 take n t = unstream (S.take n (stream t))
538 take n t = unstream (S.take n (stream t))
@@ -1083,36 +540,23 @@ iterN n t@(Text _arr _off len) = loop 0 0
1083 unstream (S.take n (stream t)) = take n t
540 unstream (S.take n (stream t)) = take n t
1086−-- | /O(n)/ 'takeEnd' @n@ @t@ returns the suffix remaining after
1087−-- taking @n@ characters from the end of @t@.
1091−-- > takeEnd 3 "foobar" == "bar"
1092−takeEnd :: Int -> Text -> Text
1093−takeEnd n t@(Text arr off len)
1096− | otherwise = text arr (off+i) (len-i)
1097− where i = iterNEnd n t
1099−iterNEnd :: Int -> Text -> Int
1100−iterNEnd n t@(Text _arr _off len) = loop (len-1) n
1104− | otherwise = loop (i+d) (m-1)
1105− where d = reverseIter_ t i
1107-- | /O(n)/ 'drop' @n@, applied to a 'Text', returns the suffix of the
543-- | /O(n)/ 'drop' @n@, applied to a 'Text', returns the suffix of the
1108−-- 'Text' after the first @n@ characters, or the empty 'Text' if @n@
544+-- 'Text' of length @n@, or the empty 'Text' if @n@ is greater than the
1109−-- is greater than the length of the 'Text'. Subject to fusion.
545+-- length of the 'Text'.
1110drop :: Int -> Text -> Text
546drop :: Int -> Text -> Text
1111drop n t@(Text arr off len)
547drop n t@(Text arr off len)
1112 | n <= 0 = t
548 | n <= 0 = t
1113 | n >= len = empty
549 | n >= len = empty
1114− | otherwise = text arr (off+i) (len-i)
550+ | otherwise = Text arr newOff newLen
1115− where i = iterN n t
551+ where
552+ (newOff, newLen) = loop off 0 len
555+ | i >= end || count >= n = (i,l)
556+ | c < 0xD800 || c > 0xDBFF = loop (i+1) (count+1) (l-1)
557+ | otherwise = loop (i+2) (count+1) (l-2)
559+ c = arr `A.unsafeIndex` i
1116{-# INLINE [1] drop #-}
560{-# INLINE [1] drop #-}
1118{-# RULES
562{-# RULES
@@ -1122,282 +566,55 @@ drop n t@(Text arr off len)
1122 unstream (S.drop n (stream t)) = drop n t
566 unstream (S.drop n (stream t)) = drop n t
1125−-- | /O(n)/ 'dropEnd' @n@ @t@ returns the prefix remaining after
1126−-- dropping @n@ characters from the end of @t@.
1130−-- > dropEnd 3 "foobar" == "foo"
1131−dropEnd :: Int -> Text -> Text
1132−dropEnd n t@(Text arr off len)
1135− | otherwise = text arr off (iterNEnd n t)
1137−-- | /O(n)/ 'takeWhile', applied to a predicate @p@ and a 'Text',
569+-- | /O(n)/ 'takeWhile', applied to a predicate @p@ and a 'Text', returns the
1138−-- returns the longest prefix (possibly empty) of elements that
570+-- longest prefix (possibly empty) of elements that satisfy @p@.
1139−-- satisfy @p@. Subject to fusion.
1140takeWhile :: (Char -> Bool) -> Text -> Text
571takeWhile :: (Char -> Bool) -> Text -> Text
1141−takeWhile p t@(Text arr off len) = loop 0
572+takeWhile p t = unstream (S.takeWhile p (stream t))
1142− where loop !i | i >= len = t
1144− | otherwise = text arr off i
1145− where Iter c d = iter t i
1146−{-# INLINE [1] takeWhile #-}
573+{-# INLINE takeWhile #-}
1149−"TEXT takeWhile -> fused" [~1] forall p t.
1150− takeWhile p t = unstream (S.takeWhile p (stream t))
1151−"TEXT takeWhile -> unfused" [1] forall p t.
1152− unstream (S.takeWhile p (stream t)) = takeWhile p t
1155−-- | /O(n)/ 'takeWhileEnd', applied to a predicate @p@ and a 'Text',
1156−-- returns the longest suffix (possibly empty) of elements that
1157−-- satisfy @p@. Subject to fusion.
1160−-- > takeWhileEnd (=='o') "foo" == "oo"
1161−takeWhileEnd :: (Char -> Bool) -> Text -> Text
1162−takeWhileEnd p t@(Text arr off len) = loop (len-1) len
1163− where loop !i !l | l <= 0 = t
1164− | p c = loop (i+d) (l+d)
1165− | otherwise = text arr (off+l) (len-l)
1166− where (c,d) = reverseIter t i
1167−{-# INLINE [1] takeWhileEnd #-}
1170−"TEXT takeWhileEnd -> fused" [~1] forall p t.
1171− takeWhileEnd p t = S.reverse (S.takeWhile p (S.reverseStream t))
1172−"TEXT takeWhileEnd -> unfused" [1] forall p t.
1173− S.reverse (S.takeWhile p (S.reverseStream t)) = takeWhileEnd p t
1176−-- | /O(n)/ 'dropWhile' @p@ @t@ returns the suffix remaining after
575+-- | /O(n)/ 'dropWhile' @p@ @xs@ returns the suffix remaining after
1177−-- 'takeWhile' @p@ @t@. Subject to fusion.
576+-- 'takeWhile' @p@ @xs@.
1178dropWhile :: (Char -> Bool) -> Text -> Text
577dropWhile :: (Char -> Bool) -> Text -> Text
1179−dropWhile p t@(Text arr off len) = loop 0 0
1180− where loop !i !l | l >= len = empty
1181− | p c = loop (i+d) (l+d)
1182− | otherwise = Text arr (off+i) (len-l)
1183− where Iter c d = iter t i
1184−{-# INLINE [1] dropWhile #-}
1187−"TEXT dropWhile -> fused" [~1] forall p t.
1188− dropWhile p t = unstream (S.dropWhile p (stream t))
578+dropWhile p t = unstream (S.dropWhile p (stream t))
1189−"TEXT dropWhile -> unfused" [1] forall p t.
579+{-# INLINE dropWhile #-}
1190− unstream (S.dropWhile p (stream t)) = dropWhile p t
1193−-- | /O(n)/ 'dropWhileEnd' @p@ @t@ returns the prefix remaining after
1194−-- dropping characters that satisfy the predicate @p@ from the end of
1195−-- @t@. Subject to fusion.
1199−-- > dropWhileEnd (=='.') "foo..." == "foo"
1200−dropWhileEnd :: (Char -> Bool) -> Text -> Text
1201−dropWhileEnd p t@(Text arr off len) = loop (len-1) len
1202− where loop !i !l | l <= 0 = empty
1203− | p c = loop (i+d) (l+d)
1204− | otherwise = Text arr off l
1205− where (c,d) = reverseIter t i
1206−{-# INLINE [1] dropWhileEnd #-}
1209−"TEXT dropWhileEnd -> fused" [~1] forall p t.
1210− dropWhileEnd p t = S.reverse (S.dropWhile p (S.reverseStream t))
1211−"TEXT dropWhileEnd -> unfused" [1] forall p t.
1212− S.reverse (S.dropWhile p (S.reverseStream t)) = dropWhileEnd p t
1215−-- | /O(n)/ 'dropAround' @p@ @t@ returns the substring remaining after
1216−-- dropping characters that satisfy the predicate @p@ from both the
1217−-- beginning and end of @t@. Subject to fusion.
1218−dropAround :: (Char -> Bool) -> Text -> Text
1219−dropAround p = dropWhile p . dropWhileEnd p
1220−{-# INLINE [1] dropAround #-}
1222−-- | /O(n)/ Remove leading white space from a string. Equivalent to:
1224−-- > dropWhile isSpace
1225−stripStart :: Text -> Text
1226−stripStart = dropWhile isSpace
1227−{-# INLINE [1] stripStart #-}
1229−-- | /O(n)/ Remove trailing white space from a string. Equivalent to:
1231−-- > dropWhileEnd isSpace
1232−stripEnd :: Text -> Text
1233−stripEnd = dropWhileEnd isSpace
1234−{-# INLINE [1] stripEnd #-}
1236−-- | /O(n)/ Remove leading and trailing white space from a string.
1239−-- > dropAround isSpace
1240−strip :: Text -> Text
1241−strip = dropAround isSpace
1242−{-# INLINE [1] strip #-}
1244−-- | /O(n)/ 'splitAt' @n t@ returns a pair whose first element is a
1245−-- prefix of @t@ of length @n@, and whose second is the remainder of
1246−-- the string. It is equivalent to @('take' n t, 'drop' n t)@.
1247−splitAt :: Int -> Text -> (Text, Text)
1248−splitAt n t@(Text arr off len)
1249− | n <= 0 = (empty, t)
1250− | n >= len = (t, empty)
1251− | otherwise = let k = iterN n t
1252− in (text arr off k, text arr (off+k) (len-k))
1254−-- | /O(n)/ 'span', applied to a predicate @p@ and text @t@, returns
1255−-- a pair whose first element is the longest prefix (possibly empty)
1256−-- of @t@ of elements that satisfy @p@, and whose second is the
1257−-- remainder of the list.
1258−span :: (Char -> Bool) -> Text -> (Text, Text)
1259−span p t = case span_ p t of
1260− (# hd,tl #) -> (hd,tl)
1263−-- | /O(n)/ 'break' is like 'span', but the prefix returned is
1264−-- over elements that fail the predicate @p@.
1265−break :: (Char -> Bool) -> Text -> (Text, Text)
1266−break p = span (not . p)
1267−{-# INLINE break #-}
1269−-- | /O(n)/ Group characters in a string according to a predicate.
1270−groupBy :: (Char -> Char -> Bool) -> Text -> [Text]
1273− loop t@(Text arr off len)
1275− | otherwise = text arr off n : loop (text arr (off+n) (len-n))
1276− where Iter c d = iter t 0
1277− n = d + findAIndexOrEnd (not . p c) (Text arr (off+d) (len-d))
1279−-- | Returns the /array/ index (in units of 'Word16') at which a
1280−-- character may be found. This is /not/ the same as the logical
1281−-- index returned by e.g. 'findIndex'.
1282−findAIndexOrEnd :: (Char -> Bool) -> Text -> Int
1283−findAIndexOrEnd q t@(Text _arr _off len) = go 0
1284− where go !i | i >= len || q c = i
1285− | otherwise = go (i+d)
1286− where Iter c d = iter t i
1288−-- | /O(n)/ Group characters in a string by equality.
1289−group :: Text -> [Text]
1290−group = groupBy (==)
1292-- | /O(n)/ Return all initial segments of the given 'Text', shortest
581-- | /O(n)/ Return all initial segments of the given 'Text', shortest
1293-- first.
582-- first.
1294inits :: Text -> [Text]
583inits :: Text -> [Text]
1295−inits t@(Text arr off len) = loop 0
584+inits t@(Text arr off len) = loop off
1296 where loop i | i >= len = [t]
585 where loop i | i >= len = [t]
1297− | otherwise = Text arr off i : loop (i + iter_ t i)
586+ | otherwise = Text arr off i : loop j
587+ where j | n < 0xDC00 || n > 0xDFFF = i + 1
589+ n = A.unsafeIndex arr i
1299-- | /O(n)/ Return all final segments of the given 'Text', longest
591-- | /O(n)/ Return all final segments of the given 'Text', longest
1300-- first.
592-- first.
1301tails :: Text -> [Text]
593tails :: Text -> [Text]
1302tails t | null t = [empty]
594tails t | null t = [empty]
1303− | otherwise = t : tails (unsafeTail t)
595+ | otherwise = t : tails (tail t)
1307−-- Splitting functions in this library do not perform character-wise
1308−-- copies to create substrings; they just construct new 'Text's that
1309−-- are slices of the original.
1311−-- | /O(m+n)/ Break a 'Text' into pieces separated by the first 'Text'
1312−-- argument (which cannot be empty), consuming the delimiter. An empty
1313−-- delimiter is invalid, and will cause an error to be raised.
1317−-- > splitOn "\r\n" "a\r\nb\r\nd\r\ne" == ["a","b","d","e"]
1318−-- > splitOn "aaa" "aaaXaaaXaaaXaaa" == ["","X","X","X",""]
1319−-- > splitOn "x" "x" == ["",""]
1323−-- > intercalate s . splitOn s == id
1324−-- > splitOn (singleton c) == split (==c)
1326−-- (Note: the string @s@ to split on above cannot be empty.)
1328−-- In (unlikely) bad cases, this function's time complexity degrades
1329−-- towards /O(n*m)/.
1331− -- ^ String to split on. If this string is empty, an error
1336−splitOn pat@(Text _ _ l) src@(Text arr off len)
1337− | l <= 0 = emptyError "splitOn"
1338− | isSingleton pat = split (== unsafeHead pat) src
1339− | otherwise = go 0 (indices pat src)
1341− go !s (x:xs) = text arr (s+off) (x-s) : go (x+l) xs
1342− go s _ = [text arr (s+off) (len-s)]
1343−{-# INLINE [1] splitOn #-}
1346−"TEXT splitOn/singleton -> split/==" [~1] forall c t.
1347− splitOn (singleton c) t = split (==c) t
1350−-- | /O(n)/ Splits a 'Text' into components delimited by separators,
1351−-- where the predicate returns True for a separator element. The
1352−-- resulting components do not contain the separators. Two adjacent
1353−-- separators result in an empty component in the output. eg.
1355−-- > split (=='a') "aabbaca" == ["","","bb","c",""]
1356−-- > split (=='a') "" == [""]
1357−split :: (Char -> Bool) -> Text -> [Text]
1358−split _ t@(Text _off _arr 0) = [t]
1360− where loop s | null s' = [l]
1361− | otherwise = l : loop (unsafeTail s')
1362− where (# l, s' #) = span_ (not . p) s
1363−{-# INLINE split #-}
1365−-- | /O(n)/ Splits a 'Text' into components of length @k@. The last
1366−-- element may be shorter than the other chunks, depending on the
1367−-- length of the input. Examples:
1369−-- > chunksOf 3 "foobarbaz" == ["foo","bar","baz"]
1370−-- > chunksOf 4 "haskell.org" == ["hask","ell.","org"]
1371−chunksOf :: Int -> Text -> [Text]
1374− go t = case splitAt k t of
1375− (a,b) | null a -> []
1376− | otherwise -> a : go b
1377−{-# INLINE chunksOf #-}
1379-- ----------------------------------------------------------------------------
597-- ----------------------------------------------------------------------------
1380-- * Searching
598-- * Searching
600+-------------------------------------------------------------------------------
601+-- ** Searching by equality
603+-- | /O(n)/ 'elem' is the 'Text' membership predicate.
604+elem :: Char -> Text -> Bool
605+elem c t = S.elem c (stream t)
1382-------------------------------------------------------------------------------
608-------------------------------------------------------------------------------
1383-- ** Searching with a predicate
609-- ** Searching with a predicate
1385−-- | /O(n)/ The 'find' function takes a predicate and a 'Text', and
611+-- | /O(n)/ The 'find' function takes a predicate and a 'Text',
1386−-- returns the first element matching the predicate, or 'Nothing' if
612+-- and returns the first element in matching the predicate, or 'Nothing'
1387−-- there is no such element.
613+-- if there is no such element.
1388find :: (Char -> Bool) -> Text -> Maybe Char
614find :: (Char -> Bool) -> Text -> Maybe Char
1389−find p t = S.findBy p (stream t)
615+find p t = S.find p (stream t)
1390{-# INLINE find #-}
616{-# INLINE find #-}
1392−-- | /O(n)/ The 'partition' function takes a predicate and a 'Text',
1393−-- and returns the pair of 'Text's with elements which do and do not
1394−-- satisfy the predicate, respectively; i.e.
1396−-- > partition p t == (filter p t, filter (not . p) t)
1397−partition :: (Char -> Bool) -> Text -> (Text, Text)
1398−partition p t = (filter p t, filter (not . p) t)
1399−{-# INLINE partition #-}
1401-- | /O(n)/ 'filter', applied to a predicate and a 'Text',
618-- | /O(n)/ 'filter', applied to a predicate and a 'Text',
1402-- returns a 'Text' containing those characters that satisfy the
619-- returns a 'Text' containing those characters that satisfy the
1403-- predicate.
620-- predicate.
@@ -1405,200 +622,65 @@ filter :: (Char -> Bool) -> Text -> Text
1405filter p t = unstream (S.filter p (stream t))
622filter p t = unstream (S.filter p (stream t))
1406{-# INLINE filter #-}
623{-# INLINE filter #-}
1408−-- | /O(n+m)/ Find the first instance of @needle@ (which must be
1409−-- non-'null') in @haystack@. The first element of the returned tuple
1410−-- is the prefix of @haystack@ before @needle@ is matched. The second
1411−-- is the remainder of @haystack@, starting with the match.
1415−-- > breakOn "::" "a::b::c" ==> ("a", "::b::c")
1416−-- > breakOn "/" "foobar" ==> ("foobar", "")
1420−-- > append prefix match == haystack
1421−-- > where (prefix, match) = breakOn needle haystack
1423−-- If you need to break a string by a substring repeatedly (e.g. you
1424−-- want to break on every instance of a substring), use 'breakOnAll'
1425−-- instead, as it has lower startup overhead.
1427−-- In (unlikely) bad cases, this function's time complexity degrades
1428−-- towards /O(n*m)/.
1429−breakOn :: Text -> Text -> (Text, Text)
1430−breakOn pat src@(Text arr off len)
1431− | null pat = emptyError "breakOn"
1432− | otherwise = case indices pat src of
1434− (x:_) -> (text arr off x, text arr (off+x) (len-x))
1435−{-# INLINE breakOn #-}
1437−-- | /O(n+m)/ Similar to 'breakOn', but searches from the end of the
1440−-- The first element of the returned tuple is the prefix of @haystack@
1441−-- up to and including the last match of @needle@. The second is the
1442−-- remainder of @haystack@, following the match.
1444−-- > breakOnEnd "::" "a::b::c" ==> ("a::b::", "c")
1445−breakOnEnd :: Text -> Text -> (Text, Text)
1446−breakOnEnd pat src = (reverse b, reverse a)
1447− where (a,b) = breakOn (reverse pat) (reverse src)
1448−{-# INLINE breakOnEnd #-}
1450−-- | /O(n+m)/ Find all non-overlapping instances of @needle@ in
1451−-- @haystack@. Each element of the returned list consists of a pair:
1453−-- * The entire string prior to the /k/th match (i.e. the prefix)
1455−-- * The /k/th match, followed by the remainder of the string
1459−-- > breakOnAll "::" ""
1461−-- > breakOnAll "/" "a/b/c/"
1462−-- > ==> [("a", "/b/c/"), ("a/b", "/c/"), ("a/b/c", "/")]
1464−-- In (unlikely) bad cases, this function's time complexity degrades
1465−-- towards /O(n*m)/.
1467−-- The @needle@ parameter may not be empty.
1468−breakOnAll :: Text -- ^ @needle@ to search for
1469− -> Text -- ^ @haystack@ in which to search
1471−breakOnAll pat src@(Text arr off slen)
1472− | null pat = emptyError "breakOnAll"
1473− | otherwise = L.map step (indices pat src)
1475− step x = (chunk 0 x, chunk x (slen-x))
1476− chunk !n !l = text arr (n+off) l
1477−{-# INLINE breakOnAll #-}
1479-------------------------------------------------------------------------------
626-------------------------------------------------------------------------------
1480-- ** Indexing 'Text's
627-- ** Indexing 'Text's
1484−-- If you think of a 'Text' value as an array of 'Char' values (which
1485−-- it is not), you run the risk of writing inefficient code.
1487−-- An idiom that is common in some languages is to find the numeric
1488−-- offset of a character or substring, then use that number to split
1489−-- or trim the searched string. With a 'Text' value, this approach
1490−-- would require two /O(n)/ operations: one to perform the search, and
1491−-- one to operate from wherever the search ended.
1493−-- For example, suppose you have a string that you want to split on
1494−-- the substring @\"::\"@, such as @\"foo::bar::quux\"@. Instead of
1495−-- searching for the index of @\"::\"@ and taking the substrings
1496−-- before and after that index, you would instead use @breakOnAll \"::\"@.
1498−-- | /O(n)/ 'Text' index (subscript) operator, starting from 0.
629+-- | /O(1)/ 'Text' index (subscript) operator, starting from 0.
1499index :: Text -> Int -> Char
630index :: Text -> Int -> Char
1500index t n = S.index (stream t) n
631index t n = S.index (stream t) n
1501{-# INLINE index #-}
632{-# INLINE index #-}
1503−-- | /O(n)/ The 'findIndex' function takes a predicate and a 'Text'
634+-- | The 'findIndex' function takes a predicate and a 'Text' and
1504−-- and returns the index of the first element in the 'Text' satisfying
635+-- returns the index of the first element in the 'Text'
1505−-- the predicate. Subject to fusion.
636+-- satisfying the predicate.
1506findIndex :: (Char -> Bool) -> Text -> Maybe Int
637findIndex :: (Char -> Bool) -> Text -> Maybe Int
1507findIndex p t = S.findIndex p (stream t)
638findIndex p t = S.findIndex p (stream t)
1508{-# INLINE findIndex #-}
639{-# INLINE findIndex #-}
1510−-- | /O(n+m)/ The 'count' function returns the number of times the
641+-- | /O(n)/ The 'elemIndex' function returns the index of the first
1511−-- query string appears in the given 'Text'. An empty query string is
642+-- element in the given 'Text' which is equal to the query element, or
1512−-- invalid, and will cause an error to be raised.
643+-- 'Nothing' if there is no such element.
1514−-- In (unlikely) bad cases, this function's time complexity degrades
1515−-- towards /O(n*m)/.
1516−count :: Text -> Text -> Int
1518− | null pat = emptyError "count"
1519− | isSingleton pat = countChar (unsafeHead pat) src
1520− | otherwise = L.length (indices pat src)
1521−{-# INLINE [1] count #-}
1524−"TEXT count/singleton -> countChar" [~1] forall c t.
1525− count (singleton c) t = countChar c t
1528−-- | /O(n)/ The 'countChar' function returns the number of times the
1529−-- query element appears in the given 'Text'. Subject to fusion.
1530−countChar :: Char -> Text -> Int
644+elemIndex :: Char -> Text -> Maybe Int
1531−countChar c t = S.countChar c (stream t)
645+elemIndex c t = S.elemIndex c (stream t)
1532−{-# INLINE countChar #-}
1534-------------------------------------------------------------------------------
647-------------------------------------------------------------------------------
1535-- * Zipping
648-- * Zipping
1537−-- | /O(n)/ 'zip' takes two 'Text's and returns a list of
1538−-- corresponding pairs of bytes. If one input 'Text' is short,
1539−-- excess elements of the longer 'Text' are discarded. This is
1540−-- equivalent to a pair of 'unpack' operations.
1541−zip :: Text -> Text -> [(Char,Char)]
1542−zip a b = S.unstreamList $ S.zipWith (,) (stream a) (stream b)
1545-- | /O(n)/ 'zipWith' generalises 'zip' by zipping with the function
650-- | /O(n)/ 'zipWith' generalises 'zip' by zipping with the function
1546-- given as the first argument, instead of a tupling function.
651-- given as the first argument, instead of a tupling function.
1547−-- Performs replacement on invalid scalar values.
1548zipWith :: (Char -> Char -> Char) -> Text -> Text -> Text
652zipWith :: (Char -> Char -> Char) -> Text -> Text -> Text
1549−zipWith f t1 t2 = unstream (S.zipWith g (stream t1) (stream t2))
653+zipWith f t1 t2 = unstream (S.zipWith f (stream t1) (stream t2))
1550− where g a b = safe (f a b)
1551−{-# INLINE zipWith #-}
1553-- | /O(n)/ Breaks a 'Text' up into a list of words, delimited by 'Char's
655-- | /O(n)/ Breaks a 'Text' up into a list of words, delimited by 'Char's
1554-- representing white space.
656-- representing white space.
1555words :: Text -> [Text]
657words :: Text -> [Text]
1556−words t@(Text arr off len) = loop 0 0
658+words (Text arr off len) = loop0 off off
1558− loop !start !n
660+ loop0 start n
1559− | n >= len = if start == n
1561− else [Text arr (start+off) (n-start)]
1562− | isSpace c =
661+ | isSpace (unsafeChr c) = if start == n
1564− then loop (start+1) (start+1)
662+ then loop0 (start+1) (start+1)
1565− else Text arr (start+off) (n-start) : loop (n+d) (n+d)
663+ else (Text arr start (n-start)):loop0 (n+1) (n+1)
664+ | n < (off+len) = loop0 start (n+1)
1566− | otherwise = loop start (n+d)
665+ | otherwise = if start == n
667+ else [(Text arr start (n-start))]
1567− where Iter c d = iter t n
668+ where
669+ c = arr `A.unsafeIndex` n
1568{-# INLINE words #-}
670{-# INLINE words #-}
1570-- | /O(n)/ Breaks a 'Text' up into a list of 'Text's at
672-- | /O(n)/ Breaks a 'Text' up into a list of 'Text's at
1571-- newline 'Char's. The resulting strings do not contain newlines.
673-- newline 'Char's. The resulting strings do not contain newlines.
1572lines :: Text -> [Text]
675lines :: Text -> [Text]
1573−lines ps | null ps = []
676+lines ps
1574− | otherwise = h : if null t
678+ | otherwise = case search ps of
1575− then []
679+ Nothing -> [ps]
1576− else lines (unsafeTail t)
680+ Just n -> take n ps : lines (drop (n+1) ps)
1577− where (# h,t #) = span_ (/= '\n') ps
681+ where search = elemIndex '\n'
1578{-# INLINE lines #-}
682{-# INLINE lines #-}
1581−-- | /O(n)/ Portably breaks a 'Text' up into a list of 'Text's at line
1584−-- A line boundary is considered to be either a line feed, a carriage
1585−-- return immediately followed by a line feed, or a carriage return.
1586−-- This accounts for both Unix and Windows line ending conventions,
1587−-- and for the old convention used on Mac OS 9 and earlier.
1588−lines' :: Text -> [Text]
1589−lines' ps | null ps = []
1590− | otherwise = h : case uncons t of
1593− | c == '\n' -> lines t'
1594− | c == '\r' -> case uncons t' of
1595− Just ('\n',t'') -> lines t''
1597− where (h,t) = span notEOL ps
1598− notEOL c = c /= '\n' && c /= '\r'
1599−{-# INLINE lines' #-}
1602-- | /O(n)/ Joins lines, after appending a terminating newline to
684-- | /O(n)/ Joins lines, after appending a terminating newline to
1604unlines :: [Text] -> Text
686unlines :: [Text] -> Text
@@ -1610,146 +692,5 @@ unwords :: [Text] -> Text
1610unwords = intercalate (singleton ' ')
692unwords = intercalate (singleton ' ')
1611{-# INLINE unwords #-}
693{-# INLINE unwords #-}
1613−-- | /O(n)/ The 'isPrefixOf' function takes two 'Text's and returns
695+errorEmptyList :: String -> a
1614−-- 'True' iff the first is a prefix of the second. Subject to fusion.
696+errorEmptyList fun = error ("Data.Text." ++ fun ++ ": empty list")
1615−isPrefixOf :: Text -> Text -> Bool
1616−isPrefixOf a@(Text _ _ alen) b@(Text _ _ blen) =
1617− alen <= blen && S.isPrefixOf (stream a) (stream b)
1618−{-# INLINE [1] isPrefixOf #-}
1621−"TEXT isPrefixOf -> fused" [~1] forall s t.
1622− isPrefixOf s t = S.isPrefixOf (stream s) (stream t)
1625−-- | /O(n)/ The 'isSuffixOf' function takes two 'Text's and returns
1626−-- 'True' iff the first is a suffix of the second.
1627−isSuffixOf :: Text -> Text -> Bool
1628−isSuffixOf a@(Text _aarr _aoff alen) b@(Text barr boff blen) =
1630− where d = blen - alen
1632− | otherwise = Text barr (boff+d) alen
1633−{-# INLINE isSuffixOf #-}
1635−-- | /O(n+m)/ The 'isInfixOf' function takes two 'Text's and returns
1636−-- 'True' iff the first is contained, wholly and intact, anywhere
1637−-- within the second.
1639−-- In (unlikely) bad cases, this function's time complexity degrades
1640−-- towards /O(n*m)/.
1641−isInfixOf :: Text -> Text -> Bool
1642−isInfixOf needle haystack
1643− | null needle = True
1644− | isSingleton needle = S.elem (unsafeHead needle) . S.stream $ haystack
1645− | otherwise = not . L.null . indices needle $ haystack
1646−{-# INLINE [1] isInfixOf #-}
1649−"TEXT isInfixOf/singleton -> S.elem/S.stream" [~1] forall n h.
1650− isInfixOf (singleton n) h = S.elem n (S.stream h)
1653−-------------------------------------------------------------------------------
1656−-- | /O(n)/ Return the suffix of the second string if its prefix
1657−-- matches the entire first string.
1661−-- > stripPrefix "foo" "foobar" == Just "bar"
1662−-- > stripPrefix "" "baz" == Just "baz"
1663−-- > stripPrefix "foo" "quux" == Nothing
1665−-- This is particularly useful with the @ViewPatterns@ extension to
1668−-- > {-# LANGUAGE ViewPatterns #-}
1669−-- > import Data.Text as T
1671−-- > fnordLength :: Text -> Int
1672−-- > fnordLength (stripPrefix "fnord" -> Just suf) = T.length suf
1673−-- > fnordLength _ = -1
1674−stripPrefix :: Text -> Text -> Maybe Text
1675−stripPrefix p@(Text _arr _off plen) t@(Text arr off len)
1676− | p `isPrefixOf` t = Just $! text arr (off+plen) (len-plen)
1677− | otherwise = Nothing
1679−-- | /O(n)/ Find the longest non-empty common prefix of two strings
1680−-- and return it, along with the suffixes of each string at which they
1683−-- If the strings do not have a common prefix or either one is empty,
1684−-- this function returns 'Nothing'.
1688−-- > commonPrefixes "foobar" "fooquux" == Just ("foo","bar","quux")
1689−-- > commonPrefixes "veeble" "fetzer" == Nothing
1690−-- > commonPrefixes "" "baz" == Nothing
1691−commonPrefixes :: Text -> Text -> Maybe (Text,Text,Text)
1692−commonPrefixes t0@(Text arr0 off0 len0) t1@(Text arr1 off1 len1) = go 0 0
1694− go !i !j | i < len0 && j < len1 && a == b = go (i+d0) (j+d1)
1695− | i > 0 = Just (Text arr0 off0 i,
1696− text arr0 (off0+i) (len0-i),
1697− text arr1 (off1+j) (len1-j))
1698− | otherwise = Nothing
1699− where Iter a d0 = iter t0 i
1700− Iter b d1 = iter t1 j
1702−-- | /O(n)/ Return the prefix of the second string if its suffix
1703−-- matches the entire first string.
1707−-- > stripSuffix "bar" "foobar" == Just "foo"
1708−-- > stripSuffix "" "baz" == Just "baz"
1709−-- > stripSuffix "foo" "quux" == Nothing
1711−-- This is particularly useful with the @ViewPatterns@ extension to
1714−-- > {-# LANGUAGE ViewPatterns #-}
1715−-- > import Data.Text as T
1717−-- > quuxLength :: Text -> Int
1718−-- > quuxLength (stripSuffix "quux" -> Just pre) = T.length pre
1719−-- > quuxLength _ = -1
1720−stripSuffix :: Text -> Text -> Maybe Text
1721−stripSuffix p@(Text _arr _off plen) t@(Text arr off len)
1722− | p `isSuffixOf` t = Just $! text arr off (len-plen)
1723− | otherwise = Nothing
1725−-- | Add a list of non-negative numbers. Errors out on overflow.
1726−sumP :: String -> [Int] -> Int
1729− | ax >= 0 = go ax xs
1730− | otherwise = overflowError fun
1734−emptyError :: String -> a
1735−emptyError fun = P.error $ "Data.Text." ++ fun ++ ": empty input"
1737−overflowError :: String -> a
1738−overflowError fun = P.error $ "Data.Text." ++ fun ++ ": size overflow"
1740−-- | /O(n)/ Make a distinct copy of the given string, sharing no
1741−-- storage with the original string.
1743−-- As an example, suppose you read a large string, of which you need
1744−-- only a small portion. If you do not use 'copy', the entire original
1745−-- array will be kept alive in memory by the smaller string. Making a
1746−-- copy \"breaks the link\" to the original array, allowing it to be
1747−-- garbage collected if there are no other live references to it.
1748−copy :: Text -> Text
1749−copy (Text arr off len) = Text (A.run go) 0 len
1751− go :: ST s (A.MArray s)
1754− A.copyI marr 0 arr off len