@@ -1,29 +1,48 @@
1−{-# LANGUAGE BangPatterns, CPP, Rank2Types #-}
1+{-# LANGUAGE BangPatterns, CPP, MagicHash, Rank2Types, UnboxedTuples #-}
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 #-}
5-- Module : Data.Text
11-- Module : Data.Text
6−-- Copyright : (c) 2008, 2009 Tom Harper,
7−-- (c) 2009, 2010 Bryan O'Sullivan,
12+-- Copyright : (c) 2009, 2010, 2011, 2012 Bryan O'Sullivan,
8−-- (c) 2009 Duncan Coutts
13+-- (c) 2009 Duncan Coutts,
14+-- (c) 2008, 2009 Tom Harper
10-- License : BSD-style
16-- License : BSD-style
11−-- Maintainer : bos@serpentine.com, rtomharper@googlemail.com,
17+-- Maintainer : bos@serpentine.com
13-- Stability : experimental
18-- Stability : experimental
14-- Portability : GHC
19-- Portability : GHC
16−-- A time and space-efficient implementation of Unicode text using
21+-- A time and space-efficient implementation of Unicode text.
17−-- packed Word16 arrays. Suitable for performance critical use, both
22+-- Suitable for performance critical use, both in terms of large data
18−-- in terms of large data quantities and high speed.
23+-- quantities and high speed.
25+-- /Note/: Read below the synopsis for important notes on the use of
20-- This module is intended to be imported @qualified@, to avoid name
28-- This module is intended to be imported @qualified@, to avoid name
21-- clashes with "Prelude" functions, e.g.
29-- clashes with "Prelude" functions, e.g.
23-- > import qualified Data.Text as T
31-- > 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 >.
25module Data.Text
38module Data.Text
40+ -- * Strict vs lazy types
27 -- * Fusion
46 -- * Fusion
28 -- $fusion
47 -- $fusion
@@ -62,6 +81,7 @@ module Data.Text
62 , toCaseFold
81 , toCaseFold
66 -- ** Justification
86 -- ** Justification
67 , justifyLeft
87 , justifyLeft
@@ -105,8 +125,11 @@ module Data.Text
106 -- ** Breaking strings
126 -- ** Breaking strings
109 , takeWhile
131 , takeWhile
110 , dropWhile
133 , dropWhile
111 , dropWhileEnd
134 , dropWhileEnd
112 , dropAround
135 , dropAround
@@ -114,10 +137,10 @@ module Data.Text
114 , stripStart
137 , stripStart
115 , stripEnd
138 , stripEnd
116 , splitAt
139 , splitAt
117− , spanBy
140+ , breakOn
119− , breakEnd
143+ , span
122 , groupBy
145 , groupBy
@@ -125,8 +148,8 @@ module Data.Text
126 -- ** Breaking into many substrings
149 -- ** Breaking into many substrings
127 -- $split
150 -- $split
130 , chunksOf
153 , chunksOf
132 -- ** Breaking into lines and words
155 -- ** Breaking into lines and words
@@ -142,165 +165,308 @@ module Data.Text
142 , isInfixOf
165 , isInfixOf
144 -- ** View patterns
167 -- ** View patterns
145− , prefixed
168+ , stripPrefix
146− , suffixed
169+ , stripSuffix
148 -- * Searching
172 -- * Searching
151− , findBy
176+ , partition
154 -- , findSubstring
178 -- , findSubstring
156 -- * Indexing
180 -- * Indexing
157 -- $index
181 -- $index
159 , findIndex
183 , findIndex
162− -- * Zipping and unzipping
186+ -- * Zipping
164 , zipWith
188 , zipWith
166 -- -* Ordered text
190 -- -* Ordered text
167 -- , sort
191 -- , sort
193+ -- * Low level operations
170−import Prelude (Char, Bool(..), Functor(..), Int, Maybe(..), String,
198+import Prelude (Char, Bool(..), Int, Maybe(..), String,
171 Eq(..), Ord(..), Ordering(..), (++),
199 Eq(..), Ord(..), Ordering(..), (++),
172− Read(..), Show(..),
200+ Read(..),
173− (&&), (||), (+), (-), (.), ($), ($!), (>>), (*),
201+ (&&), (||), (+), (-), (.), ($), ($!), (>>),
174− div, error, not, return, otherwise)
202+ not, return, otherwise, quot)
175#if defined(HAVE_DEEPSEQ)
203#if defined(HAVE_DEEPSEQ)
176−import Control.DeepSeq (NFData)
204+import Control.DeepSeq (NFData(rnf))
178#if defined(ASSERTS)
206#if defined(ASSERTS)
179import Control.Exception (assert)
207import Control.Exception (assert)
181import Data.Char (isSpace)
209import Data.Char (isSpace)
182−import Data.Data (Data(gfoldl, toConstr, gunfold, dataTypeOf))
210+import Data.Data (Data(gfoldl, toConstr, gunfold, dataTypeOf), constrIndex,
183−#if __GLASGOW_HASKELL__ >= 612
211+ Constr, mkConstr, DataType, mkDataType, Fixity(Prefix))
184−import Data.Data (mkNoRepType)
186−import Data.Data (mkNorepType)
188import Control.Monad (foldM)
212import Control.Monad (foldM)
213+import Control.Monad.ST (ST)
189import qualified Data.Text.Array as A
214import qualified Data.Text.Array as A
190import qualified Data.List as L
215import qualified Data.List as L
216+import Data.Binary (Binary(get, put))
191import Data.Monoid (Monoid(..))
217import Data.Monoid (Monoid(..))
218+#if MIN_VERSION_base(4,9,0)
219+import Data.Semigroup (Semigroup(..))
192import Data.String (IsString(..))
221import Data.String (IsString(..))
193−import qualified Data.Text.Fusion as S
222+import qualified Data.Text.Internal.Fusion as S
194−import qualified Data.Text.Fusion.Common as S
223+import qualified Data.Text.Internal.Fusion.Common as S
224+import Data.Text.Encoding (decodeUtf8', encodeUtf8)
195−import Data.Text.Fusion (stream, reverseStream, unstream)
225+import Data.Text.Internal.Fusion (stream, reverseStream, unstream)
196−import Data.Text.Internal (Text(..), empty, text, textP)
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#)
197import qualified Prelude as P
229import qualified Prelude as P
198−import Data.Text.Unsafe (Iter(..), iter, iter_, reverseIter, unsafeHead, unsafeTail)
230+import Data.Text.Unsafe (Iter(..), iter, iter_, lengthWord16, reverseIter,
231+ reverseIter_, unsafeHead, unsafeTail)
199−import Data.Text.UnsafeChar (unsafeChr)
232+import Data.Text.Internal.Unsafe.Char (unsafeChr)
200−import qualified Data.Text.Encoding.Utf16 as U16
233+import qualified Data.Text.Internal.Functions as F
234+import qualified Data.Text.Internal.Encoding.Utf16 as U16
201−import Data.Text.Search (indices)
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'
272+-- A 'Text' value is a sequence of Unicode scalar values, as defined
274+-- <http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#page=35 §3.9, definition D76 of the Unicode 5.2 standard >.
275+-- As such, a 'Text' cannot contain values in the range U+D800 to
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 >.)
203-- $fusion
299-- $fusion
205-- Most of the functions in this module are subject to /fusion/,
301-- Most of the functions in this module are subject to /fusion/,
206-- meaning that a pipeline of such functions will usually allocate at
302-- meaning that a pipeline of such functions will usually allocate at
207-- most one 'Text' value.
303-- most 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\".
209instance Eq Text where
324instance Eq Text where
210− t1 == t2 = stream t1 == stream t2
325+ Text arrA offA lenA == Text arrB offB lenB
326+ | lenA == lenB = A.equal arrA offA arrB offB lenA
211 {-# INLINE (==) #-}
328 {-# INLINE (==) #-}
213instance Ord Text where
330instance Ord Text where
214− compare t1 t2 = compare (stream t1) (stream t2)
331+ compare = compareText
215− {-# INLINE compare #-}
217−instance Show Text where
218− showsPrec p ps r = showsPrec p (unpack ps) r
220instance Read Text where
333instance Read Text where
221 readsPrec p str = [(pack x,y) | (x,y) <- readsPrec p str]
334 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
223instance Monoid Text where
344instance Monoid Text where
224 mempty = empty
345 mempty = empty
346+#if MIN_VERSION_base(4,9,0)
347+ mappend = (<>) -- future-proof definition
225 mappend = append
349 mappend = append
226 mconcat = concat
351 mconcat = concat
228instance IsString Text where
353instance IsString Text where
229 fromString = pack
354 fromString = pack
356+#if __GLASGOW_HASKELL__ >= 708
357+instance Exts.IsList Text where
358+ type Item Text = Char
231#if defined(HAVE_DEEPSEQ)
363#if defined(HAVE_DEEPSEQ)
232−instance NFData Text
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
235−-- This instance preserves data abstraction at the cost of inefficiency.
375+-- | This instance preserves data abstraction at the cost of inefficiency.
236-- We omit reflection services for the sake of data abstraction.
376-- We omit reflection services for the sake of data abstraction.
238−-- This instance was created by copying the behavior of Data.Set and
239−-- Data.Map. If you feel a mistake has been made, please feel free to
240−-- submit improvements.
242−-- Original discussion is archived here:
378+-- This instance was created by copying the updated behavior of
243−
379+-- @"Data.Set".@'Data.Set.Set' and @"Data.Map".@'Data.Map.Map'. If you
244−-- "could we get a Data instance for Data.Text.Text?"
380+-- feel a mistake has been made, please feel free to submit
383+-- The original discussion is archived here:
245−-- http://groups.google.com/group/haskell-cafe/browse_thread/thread/b5bbb1b28a7e525d/0639d46852575b93
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, ... >
247instance Data Text where
390instance Data Text where
248 gfoldl f z txt = z pack `f` (unpack txt)
391 gfoldl f z txt = z pack `f` (unpack txt)
249− toConstr _ = error "Data.Text.Text.toConstr"
392+ toConstr _ = packConstr
393+ gunfold k z c = case constrIndex c of
250− gunfold _ _ = error "Data.Text.Text.gunfold"
395+ _ -> P.error "gunfold"
251−#if __GLASGOW_HASKELL__ >= 612
396+ dataTypeOf _ = textDataType
252− dataTypeOf _ = mkNoRepType "Data.Text.Text"
397+
253−#else
398+#if MIN_VERSION_base(4,7,0)
254− dataTypeOf _ = mkNorepType "Data.Text.Text"
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
257-- -----------------------------------------------------------------------------
424-- -----------------------------------------------------------------------------
258-- * Conversion to/from 'Text'
425-- * Conversion to/from 'Text'
260−-- | /O(n)/ Convert a 'String' into a 'Text'. Subject to fusion.
427+-- | /O(n)/ Convert a 'String' into a 'Text'. Subject to
428+-- fusion. Performs replacement on invalid scalar values.
261pack :: String -> Text
429pack :: String -> Text
262−pack = unstream . S.streamList
430+pack = unstream . S.map safe . S.streamList
263{-# INLINE [1] pack #-}
431{-# INLINE [1] pack #-}
265−-- | /O(n)/ Convert a Text into a String. Subject to fusion.
266−unpack :: Text -> String
267−unpack = S.unstreamList . stream
268−{-# INLINE [1] unpack #-}
270−-- | /O(1)/ Convert a character into a Text.
271−-- Subject to fusion.
272−singleton :: Char -> Text
273−singleton = unstream . S.singleton
274−{-# INLINE [1] singleton #-}
276-- -----------------------------------------------------------------------------
433-- -----------------------------------------------------------------------------
277-- * Basic functions
434-- * Basic functions
279-- | /O(n)/ Adds a character to the front of a 'Text'. This function
436-- | /O(n)/ Adds a character to the front of a 'Text'. This function
280-- is more costly than its 'List' counterpart because it requires
437-- is more costly than its 'List' counterpart because it requires
281−-- copying a new array. Subject to fusion.
438+-- copying a new array. Subject to fusion. Performs replacement on
439+-- invalid scalar values.
282cons :: Char -> Text -> Text
440cons :: Char -> Text -> Text
283−cons c t = unstream (S.cons c (stream t))
441+cons c t = unstream (S.cons (safe c) (stream t))
284{-# INLINE cons #-}
442{-# INLINE cons #-}
286-- | /O(n)/ Adds a character to the end of a 'Text'. This copies the
446-- | /O(n)/ Adds a character to the end of a 'Text'. This copies the
287-- entire array in the process, unless fused. Subject to fusion.
447-- entire array in the process, unless fused. Subject to fusion.
448+-- Performs replacement on invalid scalar values.
288snoc :: Text -> Char -> Text
449snoc :: Text -> Char -> Text
289−snoc t c = unstream (S.snoc (stream t) c)
450+snoc t c = unstream (S.snoc (stream t) (safe c))
290{-# INLINE snoc #-}
451{-# INLINE snoc #-}
292-- | /O(n)/ Appends one 'Text' to the other by copying both of them
453-- | /O(n)/ Appends one 'Text' to the other by copying both of them
293-- into a new 'Text'. Subject to fusion.
454-- into a new 'Text'. Subject to fusion.
294append :: Text -> Text -> Text
455append :: Text -> Text -> Text
295−append (Text arr1 off1 len1) (Text arr2 off2 len2) = Text (A.run x) 0 len
456+append a@(Text arr1 off1 len1) b@(Text arr2 off2 len2)
459+ | len > 0 = Text (A.run x) 0 len
460+ | otherwise = overflowError "append"
297 len = len1+len2
462 len = len1+len2
463+ x :: ST s (A.MArray s)
299− arr <- A.unsafeNew len
465+ arr <- A.new len
300− A.partialCopyI arr 0 arr1 off1 len1
466+ A.copyI arr 0 arr1 off1 len1
301− A.partialCopyI arr len1 arr2 off2 (len1+len2)
467+ A.copyI arr len1 arr2 off2 len
302 return arr
468 return arr
303−{-# INLINE append #-}
469+{-# NOINLINE append #-}
306"TEXT append -> fused" [~1] forall t1 t2.
472"TEXT append -> fused" [~1] forall t1 t2.
@@ -320,21 +486,14 @@ head t = S.head (stream t)
320uncons :: Text -> Maybe (Char, Text)
486uncons :: Text -> Maybe (Char, Text)
321uncons t@(Text arr off len)
487uncons t@(Text arr off len)
322 | len <= 0 = Nothing
488 | len <= 0 = Nothing
489+ | otherwise = Just $ let !(Iter c d) = iter t 0
323− | otherwise = Just (c, textP arr (off+d) (len-d))
490+ in (c, text arr (off+d) (len-d))
324− where Iter c d = iter t 0
325{-# INLINE [1] uncons #-}
491{-# INLINE [1] uncons #-}
327-- | Lifted from Control.Arrow and specialized.
493-- | Lifted from Control.Arrow and specialized.
328second :: (b -> c) -> (a,b) -> (a,c)
494second :: (b -> c) -> (a,b) -> (a,c)
329second f (a, b) = (a, f b)
495second f (a, b) = (a, f b)
332−"TEXT uncons -> fused" [~1] forall t.
333− uncons t = fmap (second unstream) (S.uncons (stream t))
334−"TEXT uncons -> unfused" [1] forall t.
335− fmap (second unstream) (S.uncons (stream t)) = uncons t
338-- | /O(1)/ Returns the last character of a 'Text', which must be
497-- | /O(1)/ Returns the last character of a 'Text', which must be
339-- non-empty. Subject to fusion.
498-- non-empty. Subject to fusion.
340last :: Text -> Char
499last :: Text -> Char
@@ -358,7 +517,7 @@ last (Text arr off len)
358tail :: Text -> Text
517tail :: Text -> Text
359tail t@(Text arr off len)
518tail t@(Text arr off len)
360 | len <= 0 = emptyError "tail"
519 | len <= 0 = emptyError "tail"
361− | otherwise = textP arr (off+d) (len-d)
520+ | otherwise = text arr (off+d) (len-d)
362 where d = iter_ t 0
521 where d = iter_ t 0
363{-# INLINE [1] tail #-}
522{-# INLINE [1] tail #-}
@@ -373,8 +532,8 @@ tail t@(Text arr off len)
373-- be non-empty. Subject to fusion.
532-- be non-empty. Subject to fusion.
374init :: Text -> Text
533init :: Text -> Text
375init (Text arr off len) | len <= 0 = emptyError "init"
534init (Text arr off len) | len <= 0 = emptyError "init"
376− | n >= 0xDC00 && n <= 0xDFFF = textP arr off (len-2)
535+ | n >= 0xDC00 && n <= 0xDFFF = text arr off (len-2)
377− | otherwise = textP arr off (len-1)
536+ | otherwise = text arr off (len-1)
379 n = A.unsafeIndex arr (off+len-1)
538 n = A.unsafeIndex arr (off+len-1)
380{-# INLINE [1] init #-}
539{-# INLINE [1] init #-}
@@ -413,7 +572,9 @@ isSingleton = S.isSingleton . stream
413-- Subject to fusion.
572-- Subject to fusion.
414length :: Text -> Int
573length :: Text -> Int
415length t = S.length (stream t)
574length t = S.length (stream t)
416−{-# INLINE length #-}
575+{-# INLINE [0] 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.
418-- | /O(n)/ Compare the count of characters in a 'Text' to a number.
579-- | /O(n)/ Compare the count of characters in a 'Text' to a number.
419-- Subject to fusion.
580-- Subject to fusion.
@@ -432,53 +593,55 @@ compareLength t n = S.compareLengthI (stream t) n
434"TEXT ==N/length -> compareLength/==EQ" [~1] forall t n.
595"TEXT ==N/length -> compareLength/==EQ" [~1] forall t n.
435− (==) (length t) n = compareLength t n == EQ
596+ eqInt (length t) n = compareLength t n == EQ
439"TEXT /=N/length -> compareLength//=EQ" [~1] forall t n.
600"TEXT /=N/length -> compareLength//=EQ" [~1] forall t n.
440− (/=) (length t) n = compareLength t n /= EQ
601+ neInt (length t) n = compareLength t n /= EQ
444"TEXT <N/length -> compareLength/==LT" [~1] forall t n.
605"TEXT <N/length -> compareLength/==LT" [~1] forall t n.
445− (<) (length t) n = compareLength t n == LT
606+ ltInt (length t) n = compareLength t n == LT
449"TEXT <=N/length -> compareLength//=GT" [~1] forall t n.
610"TEXT <=N/length -> compareLength//=GT" [~1] forall t n.
450− (<=) (length t) n = compareLength t n /= GT
611+ leInt (length t) n = compareLength t n /= GT
454"TEXT >N/length -> compareLength/==GT" [~1] forall t n.
615"TEXT >N/length -> compareLength/==GT" [~1] forall t n.
455− (>) (length t) n = compareLength t n == GT
616+ gtInt (length t) n = compareLength t n == GT
459"TEXT >=N/length -> compareLength//=LT" [~1] forall t n.
620"TEXT >=N/length -> compareLength//=LT" [~1] forall t n.
460− (>=) (length t) n = compareLength t n /= LT
621+ geInt (length t) n = compareLength t n /= LT
463-- -----------------------------------------------------------------------------
624-- -----------------------------------------------------------------------------
464-- * Transformations
625-- * Transformations
465-- | /O(n)/ 'map' @f@ @t@ is the 'Text' obtained by applying @f@ to
626-- | /O(n)/ 'map' @f@ @t@ is the 'Text' obtained by applying @f@ to
466−-- each element of @t@. Subject to fusion.
627+-- each element of @t@. Subject to fusion. Performs replacement on
628+-- invalid scalar values.
467map :: (Char -> Char) -> Text -> Text
629map :: (Char -> Char) -> Text -> Text
468−map f t = unstream (S.map f (stream t))
630+map f t = unstream (S.map (safe . f) (stream t))
469{-# INLINE [1] map #-}
631{-# INLINE [1] map #-}
471-- | /O(n)/ The 'intercalate' function takes a 'Text' and a list of
633-- | /O(n)/ The 'intercalate' function takes a 'Text' and a list of
472-- 'Text's and concatenates the list after interspersing the first
634-- 'Text's and concatenates the list after interspersing the first
473-- argument between each element of the list.
635-- argument between each element of the list.
474intercalate :: Text -> [Text] -> Text
636intercalate :: Text -> [Text] -> Text
475−intercalate t = concat . (L.intersperse t)
637+intercalate t = concat . (F.intersperse t)
476{-# INLINE intercalate #-}
638{-# INLINE intercalate #-}
478-- | /O(n)/ The 'intersperse' function takes a character and places it
640-- | /O(n)/ The 'intersperse' function takes a character and places it
479−-- between the characters of a 'Text'. Subject to fusion.
641+-- between the characters of a 'Text'. Subject to fusion. Performs
642+-- replacement on invalid scalar values.
480intersperse :: Char -> Text -> Text
643intersperse :: Char -> Text -> Text
481−intersperse c t = unstream (S.intersperse c (stream t))
644+intersperse c t = unstream (S.intersperse (safe c) (stream t))
482{-# INLINE intersperse #-}
645{-# INLINE intersperse #-}
484-- | /O(n)/ Reverse the characters of a string. Subject to fusion.
647-- | /O(n)/ Reverse the characters of a string. Subject to fusion.
@@ -486,13 +649,59 @@ reverse :: Text -> Text
486reverse t = S.reverse (stream t)
649reverse t = S.reverse (stream t)
487{-# INLINE reverse #-}
650{-# INLINE reverse #-}
489−-- | /O(m+n)/ Replace every occurrence of one substring with another.
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
490−replace :: Text -- ^ Text to search for
675+replace :: Text
491− -> Text -- ^ Replacement text
676+ -- ^ @needle@ to search for. If this string is empty, an
492− -> Text -- ^ Input text
677+ -- error will occur.
494−replace s d = intercalate d . split s
679+ -- ^ @replacement@ to replace @needle@ with.
495−{-# INLINE replace #-}
680+ -> Text
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
497-- ----------------------------------------------------------------------------
706-- ----------------------------------------------------------------------------
498-- ** Case conversions (folds)
707-- ** Case conversions (folds)
@@ -511,12 +720,13 @@ replace s d = intercalate d . split s
511-- /Note/: In some languages, case conversion is a locale- and
720-- /Note/: In some languages, case conversion is a locale- and
512-- context-dependent operation. The case conversion functions in this
721-- context-dependent operation. The case conversion functions in this
513-- module are /not/ locale sensitive. Programs that require locale
722-- module are /not/ locale sensitive. Programs that require locale
514−-- sensitivity should use appropriate versions of the case mapping
723+-- sensitivity should use appropriate versions of the
515−-- functions from the @text-icu@ package.
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 >.
517−-- | /O(n)/ Convert a string to folded case. This function is mainly
726+-- | /O(n)/ Convert a string to folded case. Subject to fusion.
518−-- useful for performing caseless (also known as case insensitive)
728+-- This function is mainly useful for performing caseless (also known
519−-- string comparisons.
729+-- as case insensitive) string comparisons.
521-- A string @x@ is a caseless match for a string @y@ if and only if:
731-- A string @x@ is a caseless match for a string @y@ if and only if:
@@ -531,27 +741,56 @@ replace s d = intercalate d . split s
531-- instead of itself.
741-- instead of itself.
532toCaseFold :: Text -> Text
742toCaseFold :: Text -> Text
533toCaseFold t = unstream (S.toCaseFold (stream t))
743toCaseFold t = unstream (S.toCaseFold (stream t))
534−{-# INLINE [0] toCaseFold #-}
744+{-# INLINE toCaseFold #-}
536-- | /O(n)/ Convert a string to lower case, using simple case
746-- | /O(n)/ Convert a string to lower case, using simple case
747+-- conversion. Subject to fusion.
537−-- conversion. The result string may be longer than the input string.
749+-- The result string may be longer than the input string. For
538−-- For instance, \"İ\" (Latin capital letter I with dot above,
750+-- instance, \"İ\" (Latin capital letter I with dot above,
539−-- U+0130) maps to the sequence \"i\" (Latin small letter i, U+0069) followed
751+-- U+0130) maps to the sequence \"i\" (Latin small letter i, U+0069)
540−-- by \" ̇\" (combining dot above, U+0307).
752+-- followed by \" ̇\" (combining dot above, U+0307).
541toLower :: Text -> Text
753toLower :: Text -> Text
542toLower t = unstream (S.toLower (stream t))
754toLower t = unstream (S.toLower (stream t))
543{-# INLINE toLower #-}
755{-# INLINE toLower #-}
545-- | /O(n)/ Convert a string to upper case, using simple case
757-- | /O(n)/ Convert a string to upper case, using simple case
758+-- conversion. Subject to fusion.
546−-- conversion. The result string may be longer than the input string.
760+-- The result string may be longer than the input string. For
547−-- For instance, the German \"ß\" (eszett, U+00DF) maps to the
761+-- instance, the German \"ß\" (eszett, U+00DF) maps to the
548-- two-letter sequence \"SS\".
762-- two-letter sequence \"SS\".
549toUpper :: Text -> Text
763toUpper :: Text -> Text
550toUpper t = unstream (S.toUpper (stream t))
764toUpper t = unstream (S.toUpper (stream t))
551{-# INLINE toUpper #-}
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 #-}
553-- | /O(n)/ Left-justify a string to the given length, using the
789-- | /O(n)/ Left-justify a string to the given length, using the
554−-- specified fill character on the right. Subject to fusion. Examples:
790+-- specified fill character on the right. Subject to fusion.
791+-- Performs replacement on invalid scalar values.
556-- > justifyLeft 7 'x' "foo" == "fooxxxx"
795-- > justifyLeft 7 'x' "foo" == "fooxxxx"
557-- > justifyLeft 3 'x' "foobar" == "foobar"
796-- > justifyLeft 3 'x' "foobar" == "foobar"
@@ -570,7 +809,10 @@ justifyLeft k c t
572-- | /O(n)/ Right-justify a string to the given length, using the
811-- | /O(n)/ Right-justify a string to the given length, using the
573−-- specified fill character on the left. Examples:
812+-- specified fill character on the left. Performs replacement on
813+-- invalid scalar values.
575-- > justifyRight 7 'x' "bar" == "xxxxbar"
817-- > justifyRight 7 'x' "bar" == "xxxxbar"
576-- > justifyRight 3 'x' "foobar" == "foobar"
818-- > justifyRight 3 'x' "foobar" == "foobar"
@@ -581,8 +823,11 @@ justifyRight k c t
581 where len = length t
823 where len = length t
582{-# INLINE justifyRight #-}
824{-# INLINE justifyRight #-}
584−-- | /O(n)/ Center a string to the given length, using the
826+-- | /O(n)/ Center a string to the given length, using the specified
585−-- specified fill character on either side. Examples:
827+-- fill character on either side. Performs replacement on invalid
587-- > center 8 'x' "HS" = "xxxHSxxx"
832-- > center 8 'x' "HS" = "xxxHSxxx"
588center :: Int -> Char -> Text -> Text
833center :: Int -> Char -> Text -> Text
@@ -591,7 +836,7 @@ center k c t
591 | otherwise = replicateChar l c `append` t `append` replicateChar r c
836 | otherwise = replicateChar l c `append` t `append` replicateChar r c
592 where len = length t
837 where len = length t
593 d = k - len
838 d = k - len
594− r = d `div` 2
839+ r = d `quot` 2
595 l = d - r
840 l = d - r
596{-# INLINE center #-}
841{-# INLINE center #-}
@@ -609,12 +854,12 @@ transpose ts = P.map pack (L.transpose (P.map unpack ts))
609-- (typically the left-identity of the operator), and a 'Text',
854-- (typically the left-identity of the operator), and a 'Text',
610-- reduces the 'Text' using the binary operator, from left to right.
855-- reduces the 'Text' using the binary operator, from left to right.
611-- Subject to fusion.
856-- Subject to fusion.
612−foldl :: (b -> Char -> b) -> b -> Text -> b
857+foldl :: (a -> Char -> a) -> a -> Text -> a
613foldl f z t = S.foldl f z (stream t)
858foldl f z t = S.foldl f z (stream t)
614{-# INLINE foldl #-}
859{-# INLINE foldl #-}
616-- | /O(n)/ A strict version of 'foldl'. Subject to fusion.
861-- | /O(n)/ A strict version of 'foldl'. Subject to fusion.
617−foldl' :: (b -> Char -> b) -> b -> Text -> b
862+foldl' :: (a -> Char -> a) -> a -> Text -> a
618foldl' f z t = S.foldl' f z (stream t)
863foldl' f z t = S.foldl' f z (stream t)
619{-# INLINE foldl' #-}
864{-# INLINE foldl' #-}
@@ -633,12 +878,12 @@ foldl1' f t = S.foldl1' f (stream t)
633-- (typically the right-identity of the operator), and a 'Text',
878-- (typically the right-identity of the operator), and a 'Text',
634-- reduces the 'Text' using the binary operator, from right to left.
879-- reduces the 'Text' using the binary operator, from right to left.
635-- Subject to fusion.
880-- Subject to fusion.
636−foldr :: (Char -> b -> b) -> b -> Text -> b
881+foldr :: (Char -> a -> a) -> a -> Text -> a
637foldr f z t = S.foldr f z (stream t)
882foldr f z t = S.foldr f z (stream t)
638{-# INLINE foldr #-}
883{-# INLINE foldr #-}
640-- | /O(n)/ A variant of 'foldr' that has no starting value argument,
885-- | /O(n)/ A variant of 'foldr' that has no starting value argument,
641−-- and thust must be applied to a non-empty 'Text'. Subject to
886+-- and thus must be applied to a non-empty 'Text'. Subject to
642-- fusion.
887-- fusion.
643foldr1 :: (Char -> Char -> Char) -> Text -> Char
888foldr1 :: (Char -> Char -> Char) -> Text -> Char
644foldr1 f t = S.foldr1 f (stream t)
889foldr1 f t = S.foldr1 f (stream t)
@@ -649,14 +894,19 @@ foldr1 f t = S.foldr1 f (stream t)
650-- | /O(n)/ Concatenate a list of 'Text's.
895-- | /O(n)/ Concatenate a list of 'Text's.
651concat :: [Text] -> Text
896concat :: [Text] -> Text
897+concat ts = case ts' of
652−concat ts = Text (A.run go) 0 len
900+ _ -> Text (A.run go) 0 len
654− len = L.sum (L.map (\(Text _ _ l) -> l) ts)
902+ ts' = L.filter (not . null) ts
903+ len = sumP "concat" $ L.map lengthWord16 ts'
904+ go :: ST s (A.MArray s)
656− arr <- A.unsafeNew len
906+ arr <- A.new len
907+ let step i (Text a o l) =
657− let step i (Text a o l) = let j = i + l in A.partialCopyI arr i a o j >> return j
908+ let !j = i + l in A.copyI arr i a o j >> return j
658− foldM step 0 ts >> return arr
909+ foldM step 0 ts' >> return arr
659−{-# INLINE concat #-}
661-- | /O(n)/ Map a function over a 'Text' that results in a 'Text', and
911-- | /O(n)/ Map a function over a 'Text' that results in a 'Text', and
662-- concatenate the results.
912-- concatenate the results.
@@ -665,13 +915,13 @@ concatMap f = concat . foldr ((:) . f) []
665{-# INLINE concatMap #-}
915{-# INLINE concatMap #-}
667-- | /O(n)/ 'any' @p@ @t@ determines whether any character in the
917-- | /O(n)/ 'any' @p@ @t@ determines whether any character in the
668−-- 'Text' @t@ satisifes the predicate @p@. Subject to fusion.
918+-- 'Text' @t@ satisfies the predicate @p@. Subject to fusion.
669any :: (Char -> Bool) -> Text -> Bool
919any :: (Char -> Bool) -> Text -> Bool
670any p t = S.any p (stream t)
920any p t = S.any p (stream t)
671{-# INLINE any #-}
921{-# INLINE any #-}
673-- | /O(n)/ 'all' @p@ @t@ determines whether all characters in the
923-- | /O(n)/ 'all' @p@ @t@ determines whether all characters in the
674−-- 'Text' @t@ satisify the predicate @p@. Subject to fusion.
924+-- 'Text' @t@ satisfy the predicate @p@. Subject to fusion.
675all :: (Char -> Bool) -> Text -> Bool
925all :: (Char -> Bool) -> Text -> Bool
676all p t = S.all p (stream t)
926all p t = S.all p (stream t)
677{-# INLINE all #-}
927{-# INLINE all #-}
@@ -693,6 +943,7 @@ minimum t = S.minimum (stream t)
694-- | /O(n)/ 'scanl' is similar to 'foldl', but returns a list of
944-- | /O(n)/ 'scanl' is similar to 'foldl', but returns a list of
695-- successive reduced values from the left. Subject to fusion.
945-- successive reduced values from the left. Subject to fusion.
946+-- Performs replacement on invalid scalar values.
697-- > scanl f z [x1, x2, ...] == [z, z `f` x1, (z `f` x1) `f` x2, ...]
948-- > scanl f z [x1, x2, ...] == [z, z `f` x1, (z `f` x1) `f` x2, ...]
@@ -700,11 +951,13 @@ minimum t = S.minimum (stream t)
701-- > last (scanl f z xs) == foldl f z xs.
952-- > last (scanl f z xs) == foldl f z xs.
702scanl :: (Char -> Char -> Char) -> Char -> Text -> Text
953scanl :: (Char -> Char -> Char) -> Char -> Text -> Text
703−scanl f z t = unstream (S.scanl f z (stream t))
954+scanl f z t = unstream (S.scanl g z (stream t))
955+ where g a b = safe (f a b)
704{-# INLINE scanl #-}
956{-# INLINE scanl #-}
706-- | /O(n)/ 'scanl1' is a variant of 'scanl' that has no starting
958-- | /O(n)/ 'scanl1' is a variant of 'scanl' that has no starting
707−-- value argument. Subject to fusion.
959+-- value argument. Subject to fusion. Performs replacement on
960+-- invalid scalar values.
709-- > scanl1 f [x1, x2, ...] == [x1, x1 `f` x2, ...]
962-- > scanl1 f [x1, x2, ...] == [x1, x1 `f` x2, ...]
710scanl1 :: (Char -> Char -> Char) -> Text -> Text
963scanl1 :: (Char -> Char -> Char) -> Text -> Text
@@ -712,40 +965,42 @@ scanl1 f t | null t = empty
712 | otherwise = scanl f (unsafeHead t) (unsafeTail t)
965 | otherwise = scanl f (unsafeHead t) (unsafeTail t)
713{-# INLINE scanl1 #-}
966{-# INLINE scanl1 #-}
715−-- | /O(n)/ 'scanr' is the right-to-left dual of 'scanl'.
968+-- | /O(n)/ 'scanr' is the right-to-left dual of 'scanl'. Performs
969+-- replacement on invalid scalar values.
717-- > scanr f v == reverse . scanl (flip f) v . reverse
971-- > scanr f v == reverse . scanl (flip f) v . reverse
718scanr :: (Char -> Char -> Char) -> Char -> Text -> Text
972scanr :: (Char -> Char -> Char) -> Char -> Text -> Text
719−scanr f z = S.reverse . S.reverseScanr f z . reverseStream
973+scanr f z = S.reverse . S.reverseScanr g z . reverseStream
974+ where g a b = safe (f a b)
720{-# INLINE scanr #-}
975{-# INLINE scanr #-}
722-- | /O(n)/ 'scanr1' is a variant of 'scanr' that has no starting
977-- | /O(n)/ 'scanr1' is a variant of 'scanr' that has no starting
723−-- value argument. Subject to fusion.
978+-- value argument. Subject to fusion. Performs replacement on
979+-- invalid scalar values.
724scanr1 :: (Char -> Char -> Char) -> Text -> Text
980scanr1 :: (Char -> Char -> Char) -> Text -> Text
725scanr1 f t | null t = empty
981scanr1 f t | null t = empty
726 | otherwise = scanr f (last t) (init t)
982 | otherwise = scanr f (last t) (init t)
727{-# INLINE scanr1 #-}
983{-# INLINE scanr1 #-}
729−-- | /O(n)/ Like a combination of 'map' and 'foldl'. Applies a
985+-- | /O(n)/ Like a combination of 'map' and 'foldl''. Applies a
730-- function to each element of a 'Text', passing an accumulating
986-- function to each element of a 'Text', passing an accumulating
731−-- parameter from left to right, and returns a final 'Text'.
987+-- parameter from left to right, and returns a final 'Text'. Performs
988+-- replacement on invalid scalar values.
732mapAccumL :: (a -> Char -> (a,Char)) -> a -> Text -> (a, Text)
989mapAccumL :: (a -> Char -> (a,Char)) -> a -> Text -> (a, Text)
733−mapAccumL f s t = case uncons t of
990+mapAccumL f z0 = S.mapAccumL g z0 . stream
734− Nothing -> (s, empty)
991+ where g a b = second safe (f a b)
735− Just (x, xs) -> (s'', cons y ys)
736− where (s', y ) = f s x
737− (s'',ys) = mapAccumL f s' xs
992+{-# INLINE mapAccumL #-}
739-- | The 'mapAccumR' function behaves like a combination of 'map' and
994-- | The 'mapAccumR' function behaves like a combination of 'map' and
740−-- 'foldr'; it applies a function to each element of a 'Text', passing
995+-- a strict 'foldr'; it applies a function to each element of a
741−-- an accumulating parameter from right to left, and returning a final
996+-- 'Text', passing an accumulating parameter from right to left, and
742−-- value of this accumulator together with the new 'Text'.
997+-- returning a final value of this accumulator together with the new
999+-- Performs replacement on invalid scalar values.
743mapAccumR :: (a -> Char -> (a,Char)) -> a -> Text -> (a, Text)
1000mapAccumR :: (a -> Char -> (a,Char)) -> a -> Text -> (a, Text)
744−mapAccumR f s t = case uncons t of
1001+mapAccumR f z0 = second reverse . S.mapAccumL g z0 . reverseStream
745− Nothing -> (s, empty)
1002+ where g a b = second safe (f a b)
746− Just (x, xs) -> (s'', cons y ys)
747− where (s'',y ) = f s' x
748− (s', ys) = mapAccumR f s xs
1003+{-# INLINE mapAccumR #-}
750-- -----------------------------------------------------------------------------
1005-- -----------------------------------------------------------------------------
751-- ** Generating and unfolding 'Text's
1006-- ** Generating and unfolding 'Text's
@@ -754,17 +1009,18 @@ mapAccumR f s t = case uncons t of
754-- @t@ repeated @n@ times.
1009-- @t@ repeated @n@ times.
755replicate :: Int -> Text -> Text
1010replicate :: Int -> Text -> Text
756replicate n t@(Text a o l)
1011replicate n t@(Text a o l)
757− | n <= 0 || l <= 0 = empty
1012+ | n <= 0 || l <= 0 = empty
758− | n == 1 = t
1013+ | n == 1 = t
759− | isSingleton t = replicateChar n (unsafeHead t)
1014+ | isSingleton t = replicateChar n (unsafeHead t)
760− | otherwise = Text (A.run x) 0 len
1015+ | otherwise = Text (A.run x) 0 len
762− len = l * n
1017+ len = l `mul` n
1018+ x :: ST s (A.MArray s)
764− arr <- A.unsafeNew len
1020+ arr <- A.new len
765 let loop !d !i | i >= n = return arr
1021 let loop !d !i | i >= n = return arr
766 | otherwise = let m = d + l
1022 | otherwise = let m = d + l
767− in A.partialCopyI arr d a o m >> loop m (i+1)
1023+ in A.copyI arr d a o m >> loop m (i+1)
768 loop 0 0
1024 loop 0 0
769{-# INLINE [1] replicate #-}
1025{-# INLINE [1] replicate #-}
@@ -776,7 +1032,7 @@ replicate n t@(Text a o l)
776-- | /O(n)/ 'replicateChar' @n@ @c@ is a 'Text' of length @n@ with @c@ the
1032-- | /O(n)/ 'replicateChar' @n@ @c@ is a 'Text' of length @n@ with @c@ the
777-- value of every element. Subject to fusion.
1033-- value of every element. Subject to fusion.
778replicateChar :: Int -> Char -> Text
1034replicateChar :: Int -> Char -> Text
779−replicateChar n c = unstream (S.replicateCharI n c)
1035+replicateChar n c = unstream (S.replicateCharI n (safe c))
780{-# INLINE replicateChar #-}
1036{-# INLINE replicateChar #-}
782-- | /O(n)/, where @n@ is the length of the result. The 'unfoldr'
1038-- | /O(n)/, where @n@ is the length of the result. The 'unfoldr'
@@ -785,9 +1041,9 @@ replicateChar n c = unstream (S.replicateCharI n c)
785-- returns 'Nothing' if it is done producing the 'Text', otherwise
1041-- returns 'Nothing' if it is done producing the 'Text', otherwise
786-- 'Just' @(a,b)@. In this case, @a@ is the next 'Char' in the
1042-- 'Just' @(a,b)@. In this case, @a@ is the next 'Char' in the
787-- string, and @b@ is the seed value for further production. Subject
1043-- string, and @b@ is the seed value for further production. Subject
788−-- to fusion.
1044+-- to fusion. Performs replacement on invalid scalar values.
789unfoldr :: (a -> Maybe (Char,a)) -> a -> Text
1045unfoldr :: (a -> Maybe (Char,a)) -> a -> Text
790−unfoldr f s = unstream (S.unfoldr f s)
1046+unfoldr f s = unstream (S.unfoldr (firstf safe . f) s)
791{-# INLINE unfoldr #-}
1047{-# INLINE unfoldr #-}
793-- | /O(n)/ Like 'unfoldr', 'unfoldrN' builds a 'Text' from a seed
1049-- | /O(n)/ Like 'unfoldr', 'unfoldrN' builds a 'Text' from a seed
@@ -795,9 +1051,9 @@ unfoldr f s = unstream (S.unfoldr f s)
795-- first argument to 'unfoldrN'. This function is more efficient than
1051-- first argument to 'unfoldrN'. This function is more efficient than
796-- 'unfoldr' when the maximum length of the result is known and
1052-- 'unfoldr' when the maximum length of the result is known and
797-- correct, otherwise its performance is similar to 'unfoldr'. Subject
1053-- correct, otherwise its performance is similar to 'unfoldr'. Subject
798−-- to fusion.
1054+-- to fusion. Performs replacement on invalid scalar values.
799unfoldrN :: Int -> (a -> Maybe (Char,a)) -> a -> Text
1055unfoldrN :: Int -> (a -> Maybe (Char,a)) -> a -> Text
800−unfoldrN n f s = unstream (S.unfoldrN n f s)
1056+unfoldrN n f s = unstream (S.unfoldrN n (firstf safe . f) s)
801{-# INLINE unfoldrN #-}
1057{-# INLINE unfoldrN #-}
803-- -----------------------------------------------------------------------------
1059-- -----------------------------------------------------------------------------
@@ -810,14 +1066,16 @@ take :: Int -> Text -> Text
810take n t@(Text arr off len)
1066take n t@(Text arr off len)
811 | n <= 0 = empty
1067 | n <= 0 = empty
812 | n >= len = t
1068 | n >= len = t
813− | otherwise = Text arr off (loop 0 0)
1069+ | otherwise = text arr off (iterN n t)
816− | i >= len || cnt >= n = i
817− | otherwise = loop (i+d) (cnt+1)
819{-# INLINE [1] take #-}
1070{-# 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
821{-# RULES
1079{-# RULES
822"TEXT take -> fused" [~1] forall n t.
1080"TEXT take -> fused" [~1] forall n t.
823 take n t = unstream (S.take n (stream t))
1081 take n t = unstream (S.take n (stream t))
@@ -825,6 +1083,27 @@ take n t@(Text arr off len)
825 unstream (S.take n (stream t)) = take n t
1083 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
828-- | /O(n)/ 'drop' @n@, applied to a 'Text', returns the suffix of the
1107-- | /O(n)/ 'drop' @n@, applied to a 'Text', returns the suffix of the
829-- 'Text' after the first @n@ characters, or the empty 'Text' if @n@
1108-- 'Text' after the first @n@ characters, or the empty 'Text' if @n@
830-- is greater than the length of the 'Text'. Subject to fusion.
1109-- is greater than the length of the 'Text'. Subject to fusion.
@@ -832,11 +1111,8 @@ drop :: Int -> Text -> Text
832drop n t@(Text arr off len)
1111drop n t@(Text arr off len)
833 | n <= 0 = t
1112 | n <= 0 = t
834 | n >= len = empty
1113 | n >= len = empty
835− | otherwise = loop 0 0
1114+ | otherwise = text arr (off+i) (len-i)
837− | i >= len || cnt >= n = Text arr (off+i) (len-i)
838− | otherwise = loop (i+d) (cnt+1)
839− where d = iter_ t i
1115+ where i = iterN n t
840{-# INLINE [1] drop #-}
1116{-# INLINE [1] drop #-}
842{-# RULES
1118{-# RULES
@@ -846,6 +1122,18 @@ drop n t@(Text arr off len)
846 unstream (S.drop n (stream t)) = drop n t
1122 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)
849-- | /O(n)/ 'takeWhile', applied to a predicate @p@ and a 'Text',
1137-- | /O(n)/ 'takeWhile', applied to a predicate @p@ and a 'Text',
850-- returns the longest prefix (possibly empty) of elements that
1138-- returns the longest prefix (possibly empty) of elements that
851-- satisfy @p@. Subject to fusion.
1139-- satisfy @p@. Subject to fusion.
@@ -853,7 +1141,7 @@ takeWhile :: (Char -> Bool) -> Text -> Text
853takeWhile p t@(Text arr off len) = loop 0
1141takeWhile p t@(Text arr off len) = loop 0
854 where loop !i | i >= len = t
1142 where loop !i | i >= len = t
855 | p c = loop (i+d)
1143 | p c = loop (i+d)
856− | otherwise = textP arr off i
1144+ | otherwise = text arr off i
857 where Iter c d = iter t i
1145 where Iter c d = iter t i
858{-# INLINE [1] takeWhile #-}
1146{-# INLINE [1] takeWhile #-}
@@ -864,6 +1152,27 @@ takeWhile p t@(Text arr off len) = loop 0
864 unstream (S.takeWhile p (stream t)) = takeWhile 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
867-- | /O(n)/ 'dropWhile' @p@ @t@ returns the suffix remaining after
1176-- | /O(n)/ 'dropWhile' @p@ @t@ returns the suffix remaining after
868-- 'takeWhile' @p@ @t@. Subject to fusion.
1177-- 'takeWhile' @p@ @t@. Subject to fusion.
869dropWhile :: (Char -> Bool) -> Text -> Text
1178dropWhile :: (Char -> Bool) -> Text -> Text
@@ -882,8 +1191,9 @@ dropWhile p t@(Text arr off len) = loop 0 0
884-- | /O(n)/ 'dropWhileEnd' @p@ @t@ returns the prefix remaining after
1193-- | /O(n)/ 'dropWhileEnd' @p@ @t@ returns the prefix remaining after
885−-- dropping characters that fail the predicate @p@ from the end of
1194+-- dropping characters that satisfy the predicate @p@ from the end of
886-- @t@. Subject to fusion.
1195-- @t@. Subject to fusion.
887-- Examples:
1197-- Examples:
889-- > dropWhileEnd (=='.') "foo..." == "foo"
1199-- > dropWhileEnd (=='.') "foo..." == "foo"
@@ -903,7 +1213,7 @@ dropWhileEnd p t@(Text arr off len) = loop (len-1) len
905-- | /O(n)/ 'dropAround' @p@ @t@ returns the substring remaining after
1215-- | /O(n)/ 'dropAround' @p@ @t@ returns the substring remaining after
906−-- dropping characters that fail the predicate @p@ from both the
1216+-- dropping characters that satisfy the predicate @p@ from both the
907-- beginning and end of @t@. Subject to fusion.
1217-- beginning and end of @t@. Subject to fusion.
908dropAround :: (Char -> Bool) -> Text -> Text
1218dropAround :: (Char -> Bool) -> Text -> Text
909dropAround p = dropWhile p . dropWhileEnd p
1219dropAround p = dropWhile p . dropWhileEnd p
@@ -938,31 +1248,23 @@ splitAt :: Int -> Text -> (Text, Text)
938splitAt n t@(Text arr off len)
1248splitAt n t@(Text arr off len)
939 | n <= 0 = (empty, t)
1249 | n <= 0 = (empty, t)
940 | n >= len = (t, empty)
1250 | n >= len = (t, empty)
941− | otherwise = (Text arr off k, Text arr (off+k) (len-k))
1251+ | otherwise = let k = iterN n t
942− where k = loop 0 0
1252+ in (text arr off k, text arr (off+k) (len-k))
944− | i >= len || cnt >= n = i
945− | otherwise = loop (i+d) (cnt+1)
947−{-# INLINE splitAt #-}
949−-- | /O(n)/ 'spanBy', applied to a predicate @p@ and text @t@, returns
1254+-- | /O(n)/ 'span', applied to a predicate @p@ and text @t@, returns
950-- a pair whose first element is the longest prefix (possibly empty)
1255-- a pair whose first element is the longest prefix (possibly empty)
951-- of @t@ of elements that satisfy @p@, and whose second is the
1256-- of @t@ of elements that satisfy @p@, and whose second is the
952-- remainder of the list.
1257-- remainder of the list.
953−spanBy :: (Char -> Bool) -> Text -> (Text, Text)
1258+span :: (Char -> Bool) -> Text -> (Text, Text)
954−spanBy p t@(Text arr off len) = (textP arr off k, textP arr (off+k) (len-k))
1259+span p t = case span_ p t of
955− where k = loop 0
1260+ (# hd,tl #) -> (hd,tl)
956− loop !i | i >= len || not (p c) = i
957− | otherwise = loop (i+d)
958− where Iter c d = iter t i
959−{-# INLINE spanBy #-}
1261+{-# INLINE span #-}
961−-- | /O(n)/ 'breakBy' is like 'spanBy', but the prefix returned is
1263+-- | /O(n)/ 'break' is like 'span', but the prefix returned is
962-- over elements that fail the predicate @p@.
1264-- over elements that fail the predicate @p@.
963−breakBy :: (Char -> Bool) -> Text -> (Text, Text)
1265+break :: (Char -> Bool) -> Text -> (Text, Text)
964−breakBy p = spanBy (not . p)
1266+break p = span (not . p)
965−{-# INLINE breakBy #-}
1267+{-# INLINE break #-}
967-- | /O(n)/ Group characters in a string according to a predicate.
1269-- | /O(n)/ Group characters in a string according to a predicate.
968groupBy :: (Char -> Char -> Bool) -> Text -> [Text]
1270groupBy :: (Char -> Char -> Bool) -> Text -> [Text]
@@ -982,7 +1284,7 @@ findAIndexOrEnd q t@(Text _arr _off len) = go 0
982 where go !i | i >= len || q c = i
1284 where go !i | i >= len || q c = i
983 | otherwise = go (i+d)
1285 | otherwise = go (i+d)
984 where Iter c d = iter t i
1286 where Iter c d = iter t i
986-- | /O(n)/ Group characters in a string by equality.
1288-- | /O(n)/ Group characters in a string by equality.
987group :: Text -> [Text]
1289group :: Text -> [Text]
988group = groupBy (==)
1290group = groupBy (==)
@@ -1006,36 +1308,43 @@ tails t | null t = [empty]
1006-- copies to create substrings; they just construct new 'Text's that
1308-- copies to create substrings; they just construct new 'Text's that
1007-- are slices of the original.
1309-- are slices of the original.
1009−-- | /O(m+n)/ Break a 'Text' into pieces separated by the first
1311+-- | /O(m+n)/ Break a 'Text' into pieces separated by the first 'Text'
1010−-- 'Text' argument, consuming the delimiter. An empty delimiter is
1312+-- argument (which cannot be empty), consuming the delimiter. An empty
1011−-- invalid, and will cause an error to be raised.
1313+-- delimiter is invalid, and will cause an error to be raised.
1013-- Examples:
1315-- Examples:
1015−-- > split "\r\n" "a\r\nb\r\nd\r\ne" == ["a","b","d","e"]
1317+-- > splitOn "\r\n" "a\r\nb\r\nd\r\ne" == ["a","b","d","e"]
1016−-- > split "aaa" "aaaXaaaXaaaXaaa" == ["","X","X","X",""]
1318+-- > splitOn "aaa" "aaaXaaaXaaaXaaa" == ["","X","X","X",""]
1017−-- > split "x" "x" == ["",""]
1319+-- > splitOn "x" "x" == ["",""]
1021−-- > intercalate s . split s == id
1323+-- > intercalate s . splitOn s == id
1022−-- > split (singleton c) == splitBy (==c)
1324+-- > splitOn (singleton c) == split (==c)
1326+-- (Note: the string @s@ to split on above cannot be empty.)
1024-- In (unlikely) bad cases, this function's time complexity degrades
1328-- In (unlikely) bad cases, this function's time complexity degrades
1025-- towards /O(n*m)/.
1329-- towards /O(n*m)/.
1026−split :: Text -> Text -> [Text]
1330+splitOn :: Text
1331+ -- ^ String to split on. If this string is empty, an error
1027−split pat@(Text _ _ l) src@(Text arr off len)
1336+splitOn pat@(Text _ _ l) src@(Text arr off len)
1028− | l <= 0 = emptyError "split"
1337+ | l <= 0 = emptyError "splitOn"
1029− | isSingleton pat = splitBy (== unsafeHead pat) src
1338+ | isSingleton pat = split (== unsafeHead pat) src
1030 | otherwise = go 0 (indices pat src)
1339 | otherwise = go 0 (indices pat src)
1032− go !s (x:xs) = textP arr (s+off) (x-s) : go (x+l) xs
1341+ go !s (x:xs) = text arr (s+off) (x-s) : go (x+l) xs
1033− go s _ = [textP arr (s+off) (len-s)]
1342+ go s _ = [text arr (s+off) (len-s)]
1034−{-# INLINE [1] split #-}
1343+{-# INLINE [1] splitOn #-}
1036{-# RULES
1345{-# RULES
1037−"TEXT split/singleton -> splitBy/==" [~1] forall c t.
1346+"TEXT splitOn/singleton -> split/==" [~1] forall c t.
1038− split (singleton c) t = splitBy (==c) t
1347+ splitOn (singleton c) t = split (==c) t
1041-- | /O(n)/ Splits a 'Text' into components delimited by separators,
1350-- | /O(n)/ Splits a 'Text' into components delimited by separators,
@@ -1043,15 +1352,15 @@ split pat@(Text _ _ l) src@(Text arr off len)
1043-- resulting components do not contain the separators. Two adjacent
1352-- resulting components do not contain the separators. Two adjacent
1044-- separators result in an empty component in the output. eg.
1353-- separators result in an empty component in the output. eg.
1046−-- > splitBy (=='a') "aabbaca" == ["","","bb","c",""]
1355+-- > split (=='a') "aabbaca" == ["","","bb","c",""]
1047−-- > splitBy (=='a') "" == [""]
1356+-- > split (=='a') "" == [""]
1048−splitBy :: (Char -> Bool) -> Text -> [Text]
1357+split :: (Char -> Bool) -> Text -> [Text]
1049−splitBy _ t@(Text _off _arr 0) = [t]
1358+split _ t@(Text _off _arr 0) = [t]
1050−splitBy p t = loop t
1359+split p t = loop t
1051 where loop s | null s' = [l]
1360 where loop s | null s' = [l]
1052 | otherwise = l : loop (unsafeTail s')
1361 | otherwise = l : loop (unsafeTail s')
1053− where (l, s') = breakBy p s
1362+ where (# l, s' #) = span_ (not . p) s
1054−{-# INLINE splitBy #-}
1363+{-# INLINE split #-}
1056-- | /O(n)/ Splits a 'Text' into components of length @k@. The last
1365-- | /O(n)/ Splits a 'Text' into components of length @k@. The last
1057-- element may be shorter than the other chunks, depending on the
1366-- element may be shorter than the other chunks, depending on the
@@ -1073,21 +1382,21 @@ chunksOf k = go
1073-------------------------------------------------------------------------------
1382-------------------------------------------------------------------------------
1074-- ** Searching with a predicate
1383-- ** Searching with a predicate
1076−-- | /O(n)/ The 'findBy' function takes a predicate and a 'Text', and
1385+-- | /O(n)/ The 'find' function takes a predicate and a 'Text', and
1077−-- returns the first element in matching the predicate, or 'Nothing'
1386+-- returns the first element matching the predicate, or 'Nothing' if
1078−-- if there is no such element.
1387+-- there is no such element.
1079−findBy :: (Char -> Bool) -> Text -> Maybe Char
1388+find :: (Char -> Bool) -> Text -> Maybe Char
1080−findBy p t = S.findBy p (stream t)
1389+find p t = S.findBy p (stream t)
1081−{-# INLINE findBy #-}
1390+{-# INLINE find #-}
1083−-- | /O(n)/ The 'partitionBy' function takes a predicate and a 'Text',
1392+-- | /O(n)/ The 'partition' function takes a predicate and a 'Text',
1084-- and returns the pair of 'Text's with elements which do and do not
1393-- and returns the pair of 'Text's with elements which do and do not
1085-- satisfy the predicate, respectively; i.e.
1394-- satisfy the predicate, respectively; i.e.
1087−-- > partitionBy p t == (filter p t, filter (not . p) t)
1396+-- > partition p t == (filter p t, filter (not . p) t)
1088−partitionBy :: (Char -> Bool) -> Text -> (Text, Text)
1397+partition :: (Char -> Bool) -> Text -> (Text, Text)
1089−partitionBy p t = (filter p t, filter (not . p) t)
1398+partition p t = (filter p t, filter (not . p) t)
1090−{-# INLINE partitionBy #-}
1399+{-# INLINE partition #-}
1092-- | /O(n)/ 'filter', applied to a predicate and a 'Text',
1401-- | /O(n)/ 'filter', applied to a predicate and a 'Text',
1093-- returns a 'Text' containing those characters that satisfy the
1402-- returns a 'Text' containing those characters that satisfy the
@@ -1103,39 +1412,40 @@ filter p t = unstream (S.filter p (stream t))
1104-- Examples:
1413-- Examples:
1106−-- > break "::" "a::b::c" ==> ("a", "::b::c")
1415+-- > breakOn "::" "a::b::c" ==> ("a", "::b::c")
1107−-- > break "/" "foobar" ==> ("foobar", "")
1416+-- > breakOn "/" "foobar" ==> ("foobar", "")
1111-- > append prefix match == haystack
1420-- > append prefix match == haystack
1112−-- > where (prefix, match) = break needle haystack
1421+-- > where (prefix, match) = breakOn needle haystack
1114-- If you need to break a string by a substring repeatedly (e.g. you
1423-- If you need to break a string by a substring repeatedly (e.g. you
1115−-- want to break on every instance of a substring), use 'find'
1424+-- want to break on every instance of a substring), use 'breakOnAll'
1116-- instead, as it has lower startup overhead.
1425-- instead, as it has lower startup overhead.
1118-- In (unlikely) bad cases, this function's time complexity degrades
1427-- In (unlikely) bad cases, this function's time complexity degrades
1119-- towards /O(n*m)/.
1428-- towards /O(n*m)/.
1120−break :: Text -> Text -> (Text, Text)
1429+breakOn :: Text -> Text -> (Text, Text)
1121−break pat src@(Text arr off len)
1430+breakOn pat src@(Text arr off len)
1122− | null pat = emptyError "break"
1431+ | null pat = emptyError "breakOn"
1123 | otherwise = case indices pat src of
1432 | otherwise = case indices pat src of
1124 [] -> (src, empty)
1433 [] -> (src, empty)
1125− (x:_) -> (textP arr off x, textP arr (off+x) (len-x))
1434+ (x:_) -> (text arr off x, text arr (off+x) (len-x))
1126−{-# INLINE break #-}
1435+{-# INLINE breakOn #-}
1128−-- | /O(n+m)/ Similar to 'break', but searches from the end of the string.
1437+-- | /O(n+m)/ Similar to 'breakOn', but searches from the end of the
1130-- The first element of the returned tuple is the prefix of @haystack@
1440-- The first element of the returned tuple is the prefix of @haystack@
1131-- up to and including the last match of @needle@. The second is the
1441-- up to and including the last match of @needle@. The second is the
1132-- remainder of @haystack@, following the match.
1442-- remainder of @haystack@, following the match.
1134−-- > breakEnd "::" "a::b::c" ==> ("a::b::", "c")
1444+-- > breakOnEnd "::" "a::b::c" ==> ("a::b::", "c")
1135−breakEnd :: Text -> Text -> (Text, Text)
1445+breakOnEnd :: Text -> Text -> (Text, Text)
1446+breakOnEnd pat src = (reverse b, reverse a)
1136−breakEnd pat src = let (a,b) = break (reverse pat) (reverse src)
1447+ where (a,b) = breakOn (reverse pat) (reverse src)
1137− in (reverse b, reverse a)
1138−{-# INLINE breakEnd #-}
1448+{-# INLINE breakOnEnd #-}
1140-- | /O(n+m)/ Find all non-overlapping instances of @needle@ in
1450-- | /O(n+m)/ Find all non-overlapping instances of @needle@ in
1141-- @haystack@. Each element of the returned list consists of a pair:
1451-- @haystack@. Each element of the returned list consists of a pair:
@@ -1146,25 +1456,25 @@ breakEnd pat src = let (a,b) = break (reverse pat) (reverse src)
1147-- Examples:
1457-- Examples:
1149−-- > find "::" ""
1459+-- > breakOnAll "::" ""
1150-- > ==> []
1460-- > ==> []
1151−-- > find "/" "a/b/c/"
1461+-- > breakOnAll "/" "a/b/c/"
1152-- > ==> [("a", "/b/c/"), ("a/b", "/c/"), ("a/b/c", "/")]
1462-- > ==> [("a", "/b/c/"), ("a/b", "/c/"), ("a/b/c", "/")]
1154-- In (unlikely) bad cases, this function's time complexity degrades
1464-- In (unlikely) bad cases, this function's time complexity degrades
1155-- towards /O(n*m)/.
1465-- towards /O(n*m)/.
1157-- The @needle@ parameter may not be empty.
1467-- The @needle@ parameter may not be empty.
1158−find :: Text -- ^ @needle@ to search for
1468+breakOnAll :: Text -- ^ @needle@ to search for
1159− -> Text -- ^ @haystack@ in which to search
1469+ -> Text -- ^ @haystack@ in which to search
1160− -> [(Text, Text)]
1470+ -> [(Text, Text)]
1161−find pat src@(Text arr off slen)
1471+breakOnAll pat src@(Text arr off slen)
1162− | null pat = emptyError "find"
1472+ | null pat = emptyError "breakOnAll"
1163 | otherwise = L.map step (indices pat src)
1473 | otherwise = L.map step (indices pat src)
1165 step x = (chunk 0 x, chunk x (slen-x))
1475 step x = (chunk 0 x, chunk x (slen-x))
1166− chunk !n !l = textP arr (n+off) l
1476+ chunk !n !l = text arr (n+off) l
1167−{-# INLINE find #-}
1477+{-# INLINE breakOnAll #-}
1169-------------------------------------------------------------------------------
1479-------------------------------------------------------------------------------
1170-- ** Indexing 'Text's
1480-- ** Indexing 'Text's
@@ -1183,7 +1493,7 @@ find pat src@(Text arr off slen)
1183-- For example, suppose you have a string that you want to split on
1493-- For example, suppose you have a string that you want to split on
1184-- the substring @\"::\"@, such as @\"foo::bar::quux\"@. Instead of
1494-- the substring @\"::\"@, such as @\"foo::bar::quux\"@. Instead of
1185-- searching for the index of @\"::\"@ and taking the substrings
1495-- searching for the index of @\"::\"@ and taking the substrings
1186−-- before and after that index, you would instead use @find \"::\"@.
1496+-- before and after that index, you would instead use @breakOnAll \"::\"@.
1188-- | /O(n)/ 'Text' index (subscript) operator, starting from 0.
1498-- | /O(n)/ 'Text' index (subscript) operator, starting from 0.
1189index :: Text -> Int -> Char
1499index :: Text -> Int -> Char
@@ -1230,13 +1540,15 @@ countChar c t = S.countChar c (stream t)
1230-- equivalent to a pair of 'unpack' operations.
1540-- equivalent to a pair of 'unpack' operations.
1231zip :: Text -> Text -> [(Char,Char)]
1541zip :: Text -> Text -> [(Char,Char)]
1232zip a b = S.unstreamList $ S.zipWith (,) (stream a) (stream b)
1542zip a b = S.unstreamList $ S.zipWith (,) (stream a) (stream b)
1233−{-# INLINE [0] zip #-}
1543+{-# INLINE zip #-}
1235-- | /O(n)/ 'zipWith' generalises 'zip' by zipping with the function
1545-- | /O(n)/ 'zipWith' generalises 'zip' by zipping with the function
1236-- given as the first argument, instead of a tupling function.
1546-- given as the first argument, instead of a tupling function.
1547+-- Performs replacement on invalid scalar values.
1237zipWith :: (Char -> Char -> Char) -> Text -> Text -> Text
1548zipWith :: (Char -> Char -> Char) -> Text -> Text -> Text
1238−zipWith f t1 t2 = unstream (S.zipWith f (stream t1) (stream t2))
1549+zipWith f t1 t2 = unstream (S.zipWith g (stream t1) (stream t2))
1550+ where g a b = safe (f a b)
1239−{-# INLINE [0] zipWith #-}
1551+{-# INLINE zipWith #-}
1241-- | /O(n)/ Breaks a 'Text' up into a list of words, delimited by 'Char's
1553-- | /O(n)/ Breaks a 'Text' up into a list of words, delimited by 'Char's
1242-- representing white space.
1554-- representing white space.
@@ -1262,7 +1574,7 @@ lines ps | null ps = []
1262 | otherwise = h : if null t
1574 | otherwise = h : if null t
1264 else lines (unsafeTail t)
1576 else lines (unsafeTail t)
1265− where (h,t) = spanBy (/= '\n') ps
1577+ where (# h,t #) = span_ (/= '\n') ps
1266{-# INLINE lines #-}
1578{-# INLINE lines #-}
@@ -1299,8 +1611,7 @@ unwords = intercalate (singleton ' ')
1299{-# INLINE unwords #-}
1611{-# INLINE unwords #-}
1301-- | /O(n)/ The 'isPrefixOf' function takes two 'Text's and returns
1613-- | /O(n)/ The 'isPrefixOf' function takes two 'Text's and returns
1302−-- 'True' iff the first is a prefix of the second. This function is
1614+-- 'True' iff the first is a prefix of the second. Subject to fusion.
1303−-- subject to fusion.
1304isPrefixOf :: Text -> Text -> Bool
1615isPrefixOf :: Text -> Text -> Bool
1305isPrefixOf a@(Text _ _ alen) b@(Text _ _ blen) =
1616isPrefixOf a@(Text _ _ alen) b@(Text _ _ blen) =
1306 alen <= blen && S.isPrefixOf (stream a) (stream b)
1617 alen <= blen && S.isPrefixOf (stream a) (stream b)
@@ -1309,8 +1620,6 @@ isPrefixOf a@(Text _ _ alen) b@(Text _ _ blen) =
1309{-# RULES
1620{-# RULES
1310"TEXT isPrefixOf -> fused" [~1] forall s t.
1621"TEXT isPrefixOf -> fused" [~1] forall s t.
1311 isPrefixOf s t = S.isPrefixOf (stream s) (stream t)
1622 isPrefixOf s t = S.isPrefixOf (stream s) (stream t)
1312−"TEXT isPrefixOf -> unfused" [1] forall s t.
1313− S.isPrefixOf (stream s) (stream t) = isPrefixOf s t
1316-- | /O(n)/ The 'isSuffixOf' function takes two 'Text's and returns
1625-- | /O(n)/ The 'isSuffixOf' function takes two 'Text's and returns
@@ -1344,13 +1653,14 @@ isInfixOf needle haystack
1344-------------------------------------------------------------------------------
1653-------------------------------------------------------------------------------
1345-- * View patterns
1654-- * View patterns
1347−-- | /O(n)/ Returns the suffix of the second string if its prefix
1656+-- | /O(n)/ Return the suffix of the second string if its prefix
1348−-- matches the first.
1657+-- matches the entire first string.
1350-- Examples:
1659-- Examples:
1352−-- > prefixed "foo" "foobar" == Just "bar"
1661+-- > stripPrefix "foo" "foobar" == Just "bar"
1662+-- > stripPrefix "" "baz" == Just "baz"
1353−-- > prefixed "foo" "quux" == Nothing
1663+-- > stripPrefix "foo" "quux" == Nothing
1355-- This is particularly useful with the @ViewPatterns@ extension to
1665-- This is particularly useful with the @ViewPatterns@ extension to
1356-- GHC, as follows:
1666-- GHC, as follows:
@@ -1359,20 +1669,44 @@ isInfixOf needle haystack
1359-- > import Data.Text as T
1669-- > import Data.Text as T
1361-- > fnordLength :: Text -> Int
1671-- > fnordLength :: Text -> Int
1362−-- > fnordLength (prefixed "fnord" -> Just suf) = T.length suf
1672+-- > fnordLength (stripPrefix "fnord" -> Just suf) = T.length suf
1363−-- > fnordLength _ = -1
1673+-- > fnordLength _ = -1
1364−prefixed :: Text -> Text -> Maybe Text
1674+stripPrefix :: Text -> Text -> Maybe Text
1365−prefixed p@(Text _arr _off plen) t@(Text arr off len)
1675+stripPrefix p@(Text _arr _off plen) t@(Text arr off len)
1366− | p `isPrefixOf` t = Just $! textP arr (off+plen) (len-plen)
1676+ | p `isPrefixOf` t = Just $! text arr (off+plen) (len-plen)
1367 | otherwise = Nothing
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
1369−-- | /O(n)/ Returns the prefix of the second string if its suffix
1702+-- | /O(n)/ Return the prefix of the second string if its suffix
1370−-- matches the first.
1703+-- matches the entire first string.
1372-- Examples:
1705-- Examples:
1374−-- > suffixed "bar" "foobar" == Just "foo"
1707+-- > stripSuffix "bar" "foobar" == Just "foo"
1708+-- > stripSuffix "" "baz" == Just "baz"
1375−-- > suffixed "foo" "quux" == Nothing
1709+-- > stripSuffix "foo" "quux" == Nothing
1377-- This is particularly useful with the @ViewPatterns@ extension to
1711-- This is particularly useful with the @ViewPatterns@ extension to
1378-- GHC, as follows:
1712-- GHC, as follows:
@@ -1381,12 +1715,41 @@ prefixed p@(Text _arr _off plen) t@(Text arr off len)
1381-- > import Data.Text as T
1715-- > import Data.Text as T
1383-- > quuxLength :: Text -> Int
1717-- > quuxLength :: Text -> Int
1384−-- > quuxLength (suffixed "quux" -> Just pre) = T.length pre
1718+-- > quuxLength (stripSuffix "quux" -> Just pre) = T.length pre
1385−-- > quuxLength _ = -1
1719+-- > quuxLength _ = -1
1386−suffixed :: Text -> Text -> Maybe Text
1720+stripSuffix :: Text -> Text -> Maybe Text
1387−suffixed p@(Text _arr _off plen) t@(Text arr off len)
1721+stripSuffix p@(Text _arr _off plen) t@(Text arr off len)
1388− | p `isSuffixOf` t = Just $! textP arr off (len-plen)
1722+ | p `isSuffixOf` t = Just $! text arr off (len-plen)
1389 | otherwise = Nothing
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
1391emptyError :: String -> a
1734emptyError :: String -> a
1392−emptyError fun = P.error ("Data.Text." ++ fun ++ ": empty input")
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