{-# LANGUAGE MagicHash, BangPatterns, UnboxedTuples, TypeFamilies, ForeignFunctionInterface, JavaScriptFFI, UnliftedFFITypes, GHCForeignImportPrim, CPP #-} {-| Manipulation of JavaScript strings, API and fusion implementation based on Data.Text by Tom Harper, Duncan Coutts, Bryan O'Sullivan e.a. -} module Data.JSString ( JSString -- * Creation and elimination , pack , unpack, unpack' , singleton , empty -- * Basic interface , cons , snoc , append , uncons , unsnoc , head , last , tail , init , null , length , compareLength -- * Transformations , map , intercalate , intersperse , transpose , reverse , replace -- ** Case conversion , toCaseFold , toLower , toUpper , toTitle -- ** Justification , justifyLeft , justifyRight , center -- * Folds , foldl , foldl' , foldl1 , foldl1' , foldr , foldr1 -- ** Special folds , concat , concatMap , any , all , maximum , minimum -- * Construction -- ** Scans , scanl , scanl1 , scanr , scanr1 -- ** Accumulating maps , mapAccumL , mapAccumR -- ** Generation and unfolding , replicate , unfoldr , unfoldrN -- * Substrings -- ** Breaking strings , take , takeEnd , drop , dropEnd , takeWhile , takeWhileEnd , dropWhile , dropWhileEnd , dropAround , strip , stripStart , stripEnd , splitAt , breakOn , breakOnEnd , break , span , group , group' , groupBy , inits , tails -- ** Breaking into many substrings , splitOn, splitOn' , split , chunksOf, chunksOf' -- ** Breaking into lines and words , lines, lines' , words, words' , unlines , unwords -- * Predicates , isPrefixOf , isSuffixOf , isInfixOf -- ** View patterns , stripPrefix , stripSuffix , commonPrefixes -- * Searching , filter , breakOnAll, breakOnAll' , find , partition -- * Indexing , index , findIndex , count -- * Zipping , zip , zipWith ) where import Prelude ( Char, Bool(..), Int, Maybe(..), String, Eq(..), Ord(..), Ordering(..), (++) , Read(..), Show(..), (&&), (||), (+), (-), (.), ($), ($!), (>>) , not, seq, return, otherwise, quot) import qualified Prelude as P import Control.DeepSeq (NFData(..)) import Data.Binary (Binary(..)) import Data.Char (isSpace) import qualified Data.List as L import Data.Data import GHC.Exts ( Int#, (+#), (-#), (>=#), (>#), isTrue#, chr#, Char(..) , Int(..), Addr#, tagToEnum#) import qualified GHC.Exts as Exts import qualified GHC.CString as GHC import qualified GHC.Base as GHC #if MIN_VERSION_base(4,9,0) import Data.Semigroup (Semigroup(..)) #endif import Unsafe.Coerce import GHCJS.Prim (JSVal) import qualified GHCJS.Prim as Prim import Data.JSString.Internal.Type import Data.JSString.Internal.Fusion (stream, unstream) import qualified Data.JSString.Internal.Fusion as S import qualified Data.JSString.Internal.Fusion.Common as S import Text.Printf (PrintfArg(..), formatString) getJSVal :: JSString -> JSVal getJSVal (JSString x) = x {-# INLINE getJSVal #-} instance Exts.IsString JSString where fromString = pack instance Exts.IsList JSString where type Item JSString = Char fromList = pack toList = unpack #if MIN_VERSION_base(4,9,0) instance Semigroup JSString where (<>) = append #endif instance P.Monoid JSString where mempty = empty #if MIN_VERSION_base(4,9,0) mappend = (<>) -- future-proof definition #else mappend = append #endif mconcat = concat instance Eq JSString where x == y = js_eq x y {- instance Binary JSString where put jss = put (encodeUtf8 jss) get = do bs <- get case decodeUtf8' bs of P.Left exn -> P.fail (P.show exn) P.Right a -> P.pure a -} #if MIN_VERSION_base(4,7,0) instance PrintfArg JSString where formatArg txt = formatString $ unpack txt #endif instance Ord JSString where compare x y = compareStrings x y equals :: JSString -> JSString -> Bool equals x y = js_eq x y {-# INLINE equals #-} compareStrings :: JSString -> JSString -> Ordering compareStrings x y = tagToEnum# (js_compare x y +# 1#) {-# INLINE compareStrings #-} -- | This instance preserves data abstraction at the cost of inefficiency. -- See Data.Text for more information instance Data JSString where gfoldl f z txt = z pack `f` (unpack txt) toConstr _ = packConstr gunfold k z c = case constrIndex c of 1 -> k (z pack) _ -> P.error "gunfold" dataTypeOf _ = jsstringDataType packConstr :: Constr packConstr = mkConstr jsstringDataType "pack" [] Prefix jsstringDataType :: DataType jsstringDataType = mkDataType "Data.JSString.JSString" [packConstr] instance Show JSString where showsPrec p ps r = showsPrec p (unpack ps) r instance Read JSString where readsPrec p str = [(pack x,y) | (x,y) <- readsPrec p str] -- ----------------------------------------------------------------------------- -- * Conversion to/from 'JSString' -- | /O(n)/ Convert a 'String' into a 'JSString'. Subject to -- fusion. pack :: String -> JSString pack x = rnf x `seq` js_pack (unsafeCoerce x) {-# INLINE [1] pack #-} {-# RULES "JSSTRING pack -> fused" [~1] forall x. pack x = unstream (S.map safe (S.streamList x)) "JSSTRING pack -> unfused" [1] forall x. unstream (S.map safe (S.streamList x)) = pack x #-} -- | /O(n)/ Convert a 'JSString' into a 'String'. Subject to fusion. unpack :: JSString -> String unpack = S.unstreamList . stream {-# INLINE [1] unpack #-} unpack' :: JSString -> String unpack' x = unsafeCoerce (js_unpack x) {-# INLINE unpack' #-} -- | /O(n)/ Convert a literal string into a JSString. Subject to fusion. unpackCString# :: Addr# -> JSString unpackCString# addr# = unstream (S.streamCString# addr#) {-# NOINLINE unpackCString# #-} {-# RULES "JSSTRING literal" forall a. unstream (S.map safe (S.streamList (GHC.unpackCString# a))) = unpackCString# a #-} {-# RULES "JSSTRING literal UTF8" forall a. unstream (S.map safe (S.streamList (GHC.unpackCStringUtf8# a))) = unpackCString# a #-} {-# RULES "JSSTRING empty literal" unstream (S.map safe (S.streamList [])) = empty_ #-} {-# RULES "JSSTRING singleton literal" forall a. unstream (S.map safe (S.streamList [a])) = singleton a #-} #if MIN_VERSION_ghcjs_prim(0,1,1) {-# RULES "JSSTRING literal prim" [0] forall a. unpackCString# a = JSString (Prim.unsafeUnpackJSStringUtf8# a) #-} #endif -- | /O(1)/ Convert a character into a 'JSString'. Subject to fusion. -- Performs replacement on invalid scalar values. singleton :: Char -> JSString singleton c = js_singleton c -- unstream . S.singleton . safe {-# INLINE [1] singleton #-} {-# RULES "JSSTRING singleton -> fused" [~1] forall a. singleton a = unstream (S.singleton (safe a)) "JSSTRING singleton -> unfused" [1] forall a. unstream (S.singleton (safe a)) = singleton a #-} -- This is intended to reduce inlining bloat. -- singleton_ :: Char -> Text -- singleton_ c = js_singleton c -- Text (A.run x) 0 len -- where x :: ST s (A.MArray s) -- x = do arr <- A.new len -- _ <- unsafeWrite arr 0 d -- return arr -- len | d < '\x10000' = 1 -- x | otherwise = 2 -- d = safe c -- {-# NOINLINE singleton_ #-} -- ----------------------------------------------------------------------------- -- * Basic functions -- | /O(n)/ Adds a character to the front of a 'JSString'. This function -- is more costly than its 'List' counterpart because it requires -- copying a new array. Subject to fusion. Performs replacement on -- invalid scalar values. cons :: Char -> JSString -> JSString cons c x = js_cons c x {-# INLINE [1] cons #-} {-# RULES "JSSTRING cons -> fused" [~1] forall c x. cons c x = unstream (S.cons (safe c) (stream x)) "JSSTRING cons -> unfused" [1] forall c x. unstream (S.cons (safe c) (stream x)) = cons c x #-} infixr 5 `cons` -- | /O(n)/ Adds a character to the end of a 'JSString'. This copies the -- entire array in the process, unless fused. Subject to fusion. -- Performs replacement on invalid scalar values. snoc :: JSString -> Char -> JSString snoc x c = js_snoc x c -- unstream (S.snoc (stream t) (safe c)) {-# INLINE [1] snoc #-} {-# RULES "JSSTRING snoc -> fused" [~1] forall x c. snoc x c = unstream (S.snoc (stream x) (safe c)) "JSSTRING snoc -> unfused" [1] forall x c. unstream (S.snoc (stream x) (safe c)) = snoc x c #-} -- | /O(n)/ Appends one 'JSString' to the other by copying both of them -- into a new 'JSString'. Subject to fusion. append :: JSString -> JSString -> JSString append x y = js_append x y {-# INLINE [1] append #-} {-# RULES "JSSTRING append -> fused" [~1] forall x1 x2. append x1 x2 = unstream (S.append (stream x1) (stream x2)) "JSSTRING append -> unfused" [1] forall x1 x2. unstream (S.append (stream x1) (stream x2)) = append x1 x2 #-} -- | /O(1)/ Returns the first character of a 'JSString', which must be -- non-empty. Subject to fusion. head :: JSString -> Char head x = case js_head x of -1# -> emptyError "head" ch -> C# (chr# ch) {-# INLINE [1] head #-} {-# RULES "JSSTRING head -> fused" [~1] forall x. head x = S.head (stream x) "JSSTRING head -> unfused" [1] forall x. S.head (stream x) = head x #-} -- | /O(1)/ Returns the first character and rest of a 'JSString', or -- 'Nothing' if empty. Subject to fusion. uncons :: JSString -> Maybe (Char, JSString) uncons x = case js_uncons x of (# -1#, _ #) -> Nothing (# cp, t #) -> Just (C# (chr# cp), t) {-# INLINE [1] uncons #-} unsnoc :: JSString -> Maybe (JSString, Char) unsnoc x = case js_unsnoc x of (# -1#, _ #) -> Nothing (# cp, t #) -> Just (t, C# (chr# cp)) {-# INLINE [1] unsnoc #-} -- | Lifted from Control.Arrow and specialized. second :: (b -> c) -> (a,b) -> (a,c) second f (a, b) = (a, f b) -- | /O(1)/ Returns the last character of a 'JSString', which must be -- non-empty. Subject to fusion. last :: JSString -> Char last x = case js_last x of -1# -> emptyError "last" c -> (C# (chr# c)) {-# INLINE [1] last #-} {-# RULES "JSSTRING last -> fused" [~1] forall x. last x = S.last (stream x) "JSSTRING last -> unfused" [1] forall x. S.last (stream x) = last x #-} -- | /O(1)/ Returns all characters after the head of a 'JSString', which -- must be non-empty. Subject to fusion. tail :: JSString -> JSString tail x = let r = js_tail x in if js_isNull r then emptyError "tail" else JSString r {-# INLINE [1] tail #-} {-# RULES "JSSTRING tail -> fused" [~1] forall x. tail x = unstream (S.tail (stream x)) "JSSTRING tail -> unfused" [1] forall x. unstream (S.tail (stream x)) = tail x #-} -- | /O(1)/ Returns all but the last character of a 'JSString', which must -- be non-empty. Subject to fusion. init :: JSString -> JSString init x = let r = js_init x in if js_isNull r then emptyError "init" else JSString r {-# INLINE [1] init #-} {-# RULES "JSSTRING init -> fused" [~1] forall t. init t = unstream (S.init (stream t)) "JSSTRING init -> unfused" [1] forall t. unstream (S.init (stream t)) = init t #-} -- | /O(1)/ Tests whether a 'JSString' is empty or not. Subject to -- fusion. null :: JSString -> Bool null x = js_null x {-# INLINE [1] null #-} {-# RULES "JSSTRING null -> fused" [~1] forall t. null t = S.null (stream t) "JSSTRING null -> unfused" [1] forall t. S.null (stream t) = null t #-} -- | /O(1)/ Tests whether a 'JSString' contains exactly one character. -- Subject to fusion. isSingleton :: JSString -> Bool isSingleton x = js_isSingleton x {-# INLINE [1] isSingleton #-} {-# RULES "JSSTRING isSingleton -> fused" [~1] forall x. isSingleton x = S.isSingleton (stream x) "JSSTRING isSingleton -> unfused" [1] forall x. S.isSingleton (stream x) = isSingleton x #-} -- | /O(n)/ Returns the number of characters in a 'JSString'. -- Subject to fusion. length :: JSString -> Int length x = S.length (stream x) {-# INLINE [0] length #-} -- length needs to be phased after the compareN/length rules otherwise -- it may inline before the rules have an opportunity to fire. -- | /O(n)/ Compare the count of characters in a 'JSString' to a number. -- Subject to fusion. -- -- This function gives the same answer as comparing against the result -- of 'length', but can short circuit if the count of characters is -- greater than the number, and hence be more efficient. compareLength :: JSString -> Int -> Ordering compareLength t n = S.compareLengthI (stream t) n {-# INLINE [1] compareLength #-} {-# RULES "JSSTRING compareN/length -> compareLength" [~1] forall t n. compare (length t) n = compareLength t n #-} {-# RULES "JSSTRING ==N/length -> compareLength/==EQ" [~1] forall t n. GHC.eqInt (length t) n = compareLength t n == EQ #-} {-# RULES "JSSTRING /=N/length -> compareLength//=EQ" [~1] forall t n. GHC.neInt (length t) n = compareLength t n /= EQ #-} {-# RULES "JSSTRING compareLength/==LT" [~1] forall t n. GHC.ltInt (length t) n = compareLength t n == LT #-} {-# RULES "JSSTRING <=N/length -> compareLength//=GT" [~1] forall t n. GHC.leInt (length t) n = compareLength t n /= GT #-} {-# RULES "JSSTRING >N/length -> compareLength/==GT" [~1] forall t n. GHC.gtInt (length t) n = compareLength t n == GT #-} {-# RULES "JSSTRING >=N/length -> compareLength//=LT" [~1] forall t n. GHC.geInt (length t) n = compareLength t n /= LT #-} -- ----------------------------------------------------------------------------- -- * Transformations -- | /O(n)/ 'map' @f@ @t@ is the 'JSString' obtained by applying @f@ to -- each element of @t@. -- -- Example: -- -- >>> let message = pack "I am not angry. Not at all." -- >>> T.map (\c -> if c == '.' then '!' else c) message -- "I am not angry! Not at all!" -- -- Subject to fusion. Performs replacement on invalid scalar values. map :: (Char -> Char) -> JSString -> JSString map f t = unstream (S.map (safe . f) (stream t)) {-# INLINE [1] map #-} -- | /O(n)/ The 'intercalate' function takes a 'JSString' and a list of -- 'JSString's and concatenates the list after interspersing the first -- argument between each element of the list. intercalate :: JSString -> [JSString] -> JSString intercalate i xs = rnf xs `seq` js_intercalate i (unsafeCoerce xs) {-# INLINE [1] intercalate #-} -- | /O(n)/ The 'intersperse' function takes a character and places it -- between the characters of a 'JSString'. -- -- Example: -- -- >>> T.intersperse '.' "SHIELD" -- "S.H.I.E.L.D" -- -- Subject to fusion. Performs replacement on invalid scalar values. intersperse :: Char -> JSString -> JSString intersperse c x = js_intersperse c x {-# INLINE [1] intersperse #-} {-# RULES "JSSTRING intersperse -> fused" [~1] forall c x. intersperse c x = unstream (S.intersperse (safe c) (stream x)) "JSSTRING intersperse -> unfused" [1] forall c x. unstream (S.intersperse (safe c) (stream x)) = intersperse c x #-} -- | /O(n)/ Reverse the characters of a string. -- -- Example: -- -- >>> T.reverse "desrever" -- "reversed" -- -- Subject to fusion. reverse :: JSString -> JSString reverse x = js_reverse x -- S.reverse (stream x) {-# INLINE [1] reverse #-} {-# RULES "JSSTRING reverse -> fused" [~1] forall x. reverse x = S.reverse (stream x) "JSSTRING reverse -> unfused" [1] forall x. S.reverse (stream x) = reverse x #-} -- | /O(m+n)/ Replace every non-overlapping occurrence of @needle@ in -- @haystack@ with @replacement@. -- -- This function behaves as though it was defined as follows: -- -- @ -- replace needle replacement haystack = -- 'intercalate' replacement ('splitOn' needle haystack) -- @ -- -- As this suggests, each occurrence is replaced exactly once. So if -- @needle@ occurs in @replacement@, that occurrence will /not/ itself -- be replaced recursively: -- -- >>> replace "oo" "foo" "oo" -- "foo" -- -- In cases where several instances of @needle@ overlap, only the -- first one will be replaced: -- -- >>> replace "ofo" "bar" "ofofo" -- "barfo" -- -- In (unlikely) bad cases, this function's time complexity degrades -- towards /O(n*m)/. replace :: JSString -- ^ @needle@ to search for. If this string is empty, an -- error will occur. -> JSString -- ^ @replacement@ to replace @needle@ with. -> JSString -- ^ @haystack@ in which to search. -> JSString replace needle replacement haystack | js_null needle = emptyError "replace" | otherwise = js_replace needle replacement haystack {-# INLINE replace #-} -- ---------------------------------------------------------------------------- -- ** Case conversions (folds) -- $case -- -- When case converting 'JSString' values, do not use combinators like -- @map toUpper@ to case convert each character of a string -- individually, as this gives incorrect results according to the -- rules of some writing systems. The whole-string case conversion -- functions from this module, such as @toUpper@, obey the correct -- case conversion rules. As a result, these functions may map one -- input character to two or three output characters. For examples, -- see the documentation of each function. -- -- /Note/: In some languages, case conversion is a locale- and -- context-dependent operation. The case conversion functions in this -- module are /not/ locale sensitive. Programs that require locale -- sensitivity should use appropriate versions of the -- . -- | /O(n)/ Convert a string to folded case. Subject to fusion. -- -- This function is mainly useful for performing caseless (also known -- as case insensitive) string comparisons. -- -- A string @x@ is a caseless match for a string @y@ if and only if: -- -- @toCaseFold x == toCaseFold y@ -- -- The result string may be longer than the input string, and may -- differ from applying 'toLower' to the input string. For instance, -- the Armenian small ligature \"ﬓ\" (men now, U+FB13) is case -- folded to the sequence \"մ\" (men, U+0574) followed by -- \"ն\" (now, U+0576), while the Greek \"µ\" (micro sign, -- U+00B5) is case folded to \"μ\" (small letter mu, U+03BC) -- instead of itself. toCaseFold :: JSString -> JSString toCaseFold t = unstream (S.toCaseFold (stream t)) {-# INLINE toCaseFold #-} -- | /O(n)/ Convert a string to lower case, using simple case -- conversion. Subject to fusion. -- -- The result string may be longer than the input string. For -- instance, \"İ\" (Latin capital letter I with dot above, -- U+0130) maps to the sequence \"i\" (Latin small letter i, U+0069) -- followed by \" ̇\" (combining dot above, U+0307). toLower :: JSString -> JSString toLower x = js_toLower x {-# INLINE [1] toLower #-} {-# RULES "JSSTRING toLower -> fused" [~1] forall x. toLower x = unstream (S.toLower (stream x)) "JSSTRING toLower -> unfused" [1] forall x. unstream (S.toLower (stream x)) = toLower x #-} -- | /O(n)/ Convert a string to upper case, using simple case -- conversion. Subject to fusion. -- -- The result string may be longer than the input string. For -- instance, the German \"ß\" (eszett, U+00DF) maps to the -- two-letter sequence \"SS\". toUpper :: JSString -> JSString toUpper x = js_toUpper x {-# INLINE [1] toUpper #-} {-# RULES "JSSTRING toUpper -> fused" [~1] forall x. toUpper x = unstream (S.toUpper(stream x)) "JSSTRING toUpper -> unfused" [1] forall x. unstream (S.toUpper (stream x)) = toUpper x #-} -- | /O(n)/ Convert a string to title case, using simple case -- conversion. Subject to fusion. -- -- The first letter of the input is converted to title case, as is -- every subsequent letter that immediately follows a non-letter. -- Every letter that immediately follows another letter is converted -- to lower case. -- -- The result string may be longer than the input string. For example, -- the Latin small ligature fl (U+FB02) is converted to the -- sequence Latin capital letter F (U+0046) followed by Latin small -- letter l (U+006C). -- -- /Note/: this function does not take language or culture specific -- rules into account. For instance, in English, different style -- guides disagree on whether the book name \"The Hill of the Red -- Fox\" is correctly title cased—but this function will -- capitalize /every/ word. toTitle :: JSString -> JSString toTitle t = unstream (S.toTitle (stream t)) {-# INLINE toTitle #-} -- | /O(n)/ Left-justify a string to the given length, using the -- specified fill character on the right. Subject to fusion. -- Performs replacement on invalid scalar values. -- -- Examples: -- -- >>> justifyLeft 7 'x' "foo" -- "fooxxxx" -- -- >>> justifyLeft 3 'x' "foobar" -- "foobar" justifyLeft :: Int -> Char -> JSString -> JSString justifyLeft k c t | len >= k = t | otherwise = t `append` replicateChar (k-len) c where len = length t {-# INLINE [1] justifyLeft #-} {-# RULES "JSSTRING justifyLeft -> fused" [~1] forall k c t. justifyLeft k c t = unstream (S.justifyLeftI k c (stream t)) "JSSTRING justifyLeft -> unfused" [1] forall k c t. unstream (S.justifyLeftI k c (stream t)) = justifyLeft k c t #-} -- | /O(n)/ Right-justify a string to the given length, using the -- specified fill character on the left. Performs replacement on -- invalid scalar values. -- -- Examples: -- -- >>> justifyRight 7 'x' "bar" -- "xxxxbar" -- -- >>> justifyRight 3 'x' "foobar" -- "foobar" justifyRight :: Int -> Char -> JSString -> JSString justifyRight k c t | len >= k = t | otherwise = replicateChar (k-len) c `append` t where len = length t {-# INLINE justifyRight #-} -- | /O(n)/ Center a string to the given length, using the specified -- fill character on either side. Performs replacement on invalid -- scalar values. -- -- Examples: -- -- >>> center 8 'x' "HS" -- "xxxHSxxx" center :: Int -> Char -> JSString -> JSString center k c t | len >= k = t | otherwise = replicateChar l c `append` t `append` replicateChar r c where len = length t d = k - len r = d `quot` 2 l = d - r {-# INLINE center #-} -- | /O(n)/ The 'transpose' function transposes the rows and columns -- of its 'JSString' argument. Note that this function uses 'pack', -- 'unpack', and the list version of transpose, and is thus not very -- efficient. -- -- Examples: -- -- >>> transpose ["green","orange"] -- ["go","rr","ea","en","ng","e"] -- -- >>> transpose ["blue","red"] -- ["br","le","ud","e"] transpose :: [JSString] -> [JSString] transpose ts = P.map pack (L.transpose (P.map unpack ts)) -- ----------------------------------------------------------------------------- -- * Reducing 'JSString's (folds) -- | /O(n)/ 'foldl', applied to a binary operator, a starting value -- (typically the left-identity of the operator), and a 'JSString', -- reduces the 'JSString' using the binary operator, from left to right. -- Subject to fusion. foldl :: (a -> Char -> a) -> a -> JSString -> a foldl f z t = S.foldl f z (stream t) {-# INLINE foldl #-} -- | /O(n)/ A strict version of 'foldl'. Subject to fusion. foldl' :: (a -> Char -> a) -> a -> JSString -> a foldl' f z t = S.foldl' f z (stream t) {-# INLINE foldl' #-} -- | /O(n)/ A variant of 'foldl' that has no starting value argument, -- and thus must be applied to a non-empty 'JSString'. Subject to fusion. foldl1 :: (Char -> Char -> Char) -> JSString -> Char foldl1 f t = S.foldl1 f (stream t) {-# INLINE foldl1 #-} -- | /O(n)/ A strict version of 'foldl1'. Subject to fusion. foldl1' :: (Char -> Char -> Char) -> JSString -> Char foldl1' f t = S.foldl1' f (stream t) {-# INLINE foldl1' #-} -- | /O(n)/ 'foldr', applied to a binary operator, a starting value -- (typically the right-identity of the operator), and a 'JSString', -- reduces the 'JSString' using the binary operator, from right to left. -- Subject to fusion. foldr :: (Char -> a -> a) -> a -> JSString -> a foldr f z t = S.foldr f z (stream t) {-# INLINE foldr #-} -- | /O(n)/ A variant of 'foldr' that has no starting value argument, -- and thus must be applied to a non-empty 'JSString'. Subject to -- fusion. foldr1 :: (Char -> Char -> Char) -> JSString -> Char foldr1 f t = S.foldr1 f (stream t) {-# INLINE foldr1 #-} -- ----------------------------------------------------------------------------- -- ** Special folds -- | /O(n)/ Concatenate a list of 'JSString's. concat :: [JSString] -> JSString concat xs = rnf xs `seq` js_concat (unsafeCoerce xs) {- case ts' of [] -> empty [t] -> t _ -> Text (A.run go) 0 len where ts' = L.filter (not . null) ts len = sumP "concat" $ L.map lengthWord16 ts' go :: ST s (A.MArray s) go = do arr <- A.new len let step i (Text a o l) = let !j = i + l in A.copyI arr i a o j >> return j foldM step 0 ts' >> return arr -} -- | /O(n)/ Map a function over a 'JSString' that results in a 'JSString', and -- concatenate the results. concatMap :: (Char -> JSString) -> JSString -> JSString concatMap f = concat . foldr ((:) . f) [] {-# INLINE concatMap #-} -- | /O(n)/ 'any' @p@ @t@ determines whether any character in the -- 'JSString' @t@ satisfies the predicate @p@. Subject to fusion. any :: (Char -> Bool) -> JSString -> Bool any p t = S.any p (stream t) {-# INLINE any #-} -- | /O(n)/ 'all' @p@ @t@ determines whether all characters in the -- 'JSString' @t@ satisify the predicate @p@. Subject to fusion. all :: (Char -> Bool) -> JSString -> Bool all p t = S.all p (stream t) {-# INLINE all #-} -- | /O(n)/ 'maximum' returns the maximum value from a 'JSString', which -- must be non-empty. Subject to fusion. maximum :: JSString -> Char maximum t = S.maximum (stream t) {-# INLINE maximum #-} -- | /O(n)/ 'minimum' returns the minimum value from a 'JSString', which -- must be non-empty. Subject to fusion. minimum :: JSString -> Char minimum t = S.minimum (stream t) {-# INLINE minimum #-} -- ----------------------------------------------------------------------------- -- * Building 'JSString's -- | /O(n)/ 'scanl' is similar to 'foldl', but returns a list of -- successive reduced values from the left. Subject to fusion. -- Performs replacement on invalid scalar values. -- -- > scanl f z [x1, x2, ...] == [z, z `f` x1, (z `f` x1) `f` x2, ...] -- -- Note that -- -- > last (scanl f z xs) == foldl f z xs. scanl :: (Char -> Char -> Char) -> Char -> JSString -> JSString scanl f z t = unstream (S.scanl g z (stream t)) where g a b = safe (f a b) {-# INLINE scanl #-} -- | /O(n)/ 'scanl1' is a variant of 'scanl' that has no starting -- value argument. Subject to fusion. Performs replacement on -- invalid scalar values. -- -- > scanl1 f [x1, x2, ...] == [x1, x1 `f` x2, ...] scanl1 :: (Char -> Char -> Char) -> JSString -> JSString scanl1 f x = case uncons x of Just (h, t) -> scanl f h t Nothing -> empty {-# INLINE scanl1 #-} -- | /O(n)/ 'scanr' is the right-to-left dual of 'scanl'. Performs -- replacement on invalid scalar values. -- -- > scanr f v == reverse . scanl (flip f) v . reverse scanr :: (Char -> Char -> Char) -> Char -> JSString -> JSString scanr f z = S.reverse . S.reverseScanr g z . S.reverseStream where g a b = safe (f a b) {-# INLINE scanr #-} -- | /O(n)/ 'scanr1' is a variant of 'scanr' that has no starting -- value argument. Subject to fusion. Performs replacement on -- invalid scalar values. scanr1 :: (Char -> Char -> Char) -> JSString -> JSString scanr1 f t | null t = empty | otherwise = scanr f (last t) (init t) {-# INLINE scanr1 #-} -- | /O(n)/ Like a combination of 'map' and 'foldl''. Applies a -- function to each element of a 'JSString', passing an accumulating -- parameter from left to right, and returns a final 'JSString'. Performs -- replacement on invalid scalar values. mapAccumL :: (a -> Char -> (a,Char)) -> a -> JSString -> (a, JSString) mapAccumL f z0 = S.mapAccumL g z0 . stream where g a b = second safe (f a b) {-# INLINE mapAccumL #-} -- | The 'mapAccumR' function behaves like a combination of 'map' and -- a strict 'foldr'; it applies a function to each element of a -- 'JSString', passing an accumulating parameter from right to left, and -- returning a final value of this accumulator together with the new -- 'JSString'. -- Performs replacement on invalid scalar values. mapAccumR :: (a -> Char -> (a,Char)) -> a -> JSString -> (a, JSString) mapAccumR f z0 = second reverse . S.mapAccumL g z0 . S.reverseStream where g a b = second safe (f a b) {-# INLINE mapAccumR #-} -- ----------------------------------------------------------------------------- -- ** Generating and unfolding 'JSString's -- | /O(n*m)/ 'replicate' @n@ @t@ is a 'JSString' consisting of the input -- @t@ repeated @n@ times. replicate :: Int -> JSString -> JSString replicate (I# n) t = js_replicate n t {- t@(Text a o l) | n <= 0 || l <= 0 = empty | n == 1 = t | isSingleton t = replicateChar n (unsafeHead t) | otherwise = Text (A.run x) 0 len where len = l `mul` n x :: ST s (A.MArray s) x = do arr <- A.new len let loop !d !i | i >= n = return arr | otherwise = let m = d + l in A.copyI arr d a o m >> loop m (i+1) loop 0 0 -} {-# INLINE [1] replicate #-} {-# RULES "JSSTRING replicate/singleton -> replicateChar" [~1] forall n c. replicate n (singleton c) = replicateChar n c #-} -- | /O(n)/ 'replicateChar' @n@ @c@ is a 'JSString' of length @n@ with @c@ the -- value of every element. Subject to fusion. replicateChar :: Int -> Char -> JSString replicateChar n c = js_replicateChar n c {-# INLINE [1] replicateChar #-} {-# RULES "JSSTRING replicateChar -> fused" [~1] forall n c. replicateChar n c = unstream (S.replicateCharI n (safe c)) "JSSTRING replicateChar -> unfused" [1] forall n c. unstream (S.replicateCharI n (safe c)) = replicateChar n c #-} -- | /O(n)/, where @n@ is the length of the result. The 'unfoldr' -- function is analogous to the List 'L.unfoldr'. 'unfoldr' builds a -- 'JSString' from a seed value. The function takes the element and -- returns 'Nothing' if it is done producing the 'JSString', otherwise -- 'Just' @(a,b)@. In this case, @a@ is the next 'Char' in the -- string, and @b@ is the seed value for further production. Subject -- to fusion. Performs replacement on invalid scalar values. unfoldr :: (a -> Maybe (Char,a)) -> a -> JSString unfoldr f s = unstream (S.unfoldr (firstf safe . f) s) {-# INLINE unfoldr #-} -- | /O(n)/ Like 'unfoldr', 'unfoldrN' builds a 'JSString' from a seed -- value. However, the length of the result should be limited by the -- first argument to 'unfoldrN'. This function is more efficient than -- 'unfoldr' when the maximum length of the result is known and -- correct, otherwise its performance is similar to 'unfoldr'. Subject -- to fusion. Performs replacement on invalid scalar values. unfoldrN :: Int -> (a -> Maybe (Char,a)) -> a -> JSString unfoldrN n f s = unstream (S.unfoldrN n (firstf safe . f) s) {-# INLINE unfoldrN #-} -- ----------------------------------------------------------------------------- -- * Substrings -- | /O(n)/ 'take' @n@, applied to a 'JSString', returns the prefix of the -- 'JSString' of length @n@, or the 'JSString' itself if @n@ is greater than -- the length of the JSString. Subject to fusion. take :: Int -> JSString -> JSString take (I# n) t = js_take n t {- t@(Text arr off len) | n <= 0 = empty | n >= len = t | otherwise = text arr off (iterN n t) -} {-# INLINE [1] take #-} {- iterN :: Int -> JSString -> Int iterN n t@(Text _arr _off len) = loop 0 0 where loop !i !cnt | i >= len || cnt >= n = i | otherwise = loop (i+d) (cnt+1) where d = iter_ t i -} {-# RULES "JSSTRING take -> fused" [~1] forall n t. take n t = unstream (S.take n (stream t)) "JSSTRING take -> unfused" [1] forall n t. unstream (S.take n (stream t)) = take n t #-} -- | /O(n)/ 'takeEnd' @n@ @t@ returns the suffix remaining after -- taking @n@ characters from the end of @t@. -- -- Examples: -- -- >>> takeEnd 3 "foobar" -- "bar" -- takeEnd :: Int -> JSString -> JSString takeEnd (I# n) x = js_takeEnd n x {- iterNEnd :: Int -> JSString -> Int iterNEnd n t@(Text _arr _off len) = loop (len-1) n where loop i !m | i <= 0 = 0 | m <= 1 = i | otherwise = loop (i+d) (m-1) where d = reverseIter_ t i -} -- | /O(n)/ 'drop' @n@, applied to a 'JSString', returns the suffix of the -- 'JSString' after the first @n@ characters, or the empty 'JSString' if @n@ -- is greater than the length of the 'JSString'. Subject to fusion. drop :: Int -> JSString -> JSString drop (I# n) x = js_drop n x {-# INLINE [1] drop #-} {-# RULES "JSSTRING drop -> fused" [~1] forall n t. drop n t = unstream (S.drop n (stream t)) "JSSTRING drop -> unfused" [1] forall n t. unstream (S.drop n (stream t)) = drop n t #-} -- | /O(n)/ 'dropEnd' @n@ @t@ returns the prefix remaining after -- dropping @n@ characters from the end of @t@. -- -- Examples: -- -- >>> dropEnd 3 "foobar" -- "foo" -- dropEnd :: Int -> JSString -> JSString dropEnd n x = js_dropEnd n x -- | /O(n)/ 'takeWhile', applied to a predicate @p@ and a 'JSString', -- returns the longest prefix (possibly empty) of elements that -- satisfy @p@. Subject to fusion. takeWhile :: (Char -> Bool) -> JSString -> JSString takeWhile p x = loop 0# (js_length x) where loop i l | isTrue# (i >=# l) = x | otherwise = case js_index i x of c | p (C# (chr# c)) -> loop (i +# charWidth c) l _ -> js_substr 0# i x {-# INLINE [1] takeWhile #-} {-# RULES "TEXT takeWhile -> fused" [~1] forall p t. takeWhile p t = unstream (S.takeWhile p (stream t)) "TEXT takeWhile -> unfused" [1] forall p t. unstream (S.takeWhile p (stream t)) = takeWhile p t #-} -- | /O(n)/ 'takeWhileEnd', applied to a predicate @p@ and a 'Text', -- returns the longest suffix (possibly empty) of elements that -- satisfy @p@. -- Examples: -- -- >>> takeWhileEnd (=='o') "foo" -- "oo" -- takeWhileEnd :: (Char -> Bool) -> JSString -> JSString takeWhileEnd p x = loop (js_length x -# 1#) where loop -1# = empty loop i = case js_uncheckedIndexR i x of c | p (C# (chr# c)) -> loop (i -# charWidth c) _ -> js_substr1 (i +# 1#) x {-# INLINE takeWhileEnd #-} -- | /O(n)/ 'dropWhile' @p@ @t@ returns the suffix remaining after -- 'takeWhile' @p@ @t@. Subject to fusion. dropWhile :: (Char -> Bool) -> JSString -> JSString dropWhile p x = loop 0# (js_length x) where loop i l | isTrue# (i >=# l) = empty | otherwise = case js_uncheckedIndex i x of c | p (C# (chr# c)) -> loop (i +# charWidth c) l _ -> js_substr1 i x {-# INLINE [1] dropWhile #-} {-# RULES "TEXT dropWhile -> fused" [~1] forall p t. dropWhile p t = unstream (S.dropWhile p (stream t)) "TEXT dropWhile -> unfused" [1] forall p t. unstream (S.dropWhile p (stream t)) = dropWhile p t #-} -- | /O(n)/ 'dropWhileEnd' @p@ @t@ returns the prefix remaining after -- dropping characters that satisfy the predicate @p@ from the end of -- @t@. Subject to fusion. -- Examples: -- -- >>> dropWhileEnd (=='.') "foo..." -- "foo" dropWhileEnd :: (Char -> Bool) -> JSString -> JSString dropWhileEnd p x = loop (js_length x -# 1#) where loop -1# = empty loop i = case js_uncheckedIndexR i x of c | p (C# (chr# c)) -> loop (i -# charWidth c) _ -> js_substr 0# (i +# 1#) x {-# INLINE [1] dropWhileEnd #-} {-# RULES "TEXT dropWhileEnd -> fused" [~1] forall p t. dropWhileEnd p t = S.reverse (S.dropWhile p (S.reverseStream t)) "TEXT dropWhileEnd -> unfused" [1] forall p t. S.reverse (S.dropWhile p (S.reverseStream t)) = dropWhileEnd p t #-} -- | /O(n)/ 'dropAround' @p@ @t@ returns the substring remaining after -- dropping characters that satisfy the predicate @p@ from both the -- beginning and end of @t@. Subject to fusion. dropAround :: (Char -> Bool) -> JSString -> JSString dropAround p = dropWhile p . dropWhileEnd p {-# INLINE [1] dropAround #-} -- | /O(n)/ Remove leading white space from a string. Equivalent to: -- -- > dropWhile isSpace stripStart :: JSString -> JSString stripStart = dropWhile isSpace {-# INLINE [1] stripStart #-} -- | /O(n)/ Remove trailing white space from a string. Equivalent to: -- -- > dropWhileEnd isSpace stripEnd :: JSString -> JSString stripEnd = dropWhileEnd isSpace {-# INLINE [1] stripEnd #-} -- | /O(n)/ Remove leading and trailing white space from a string. -- Equivalent to: -- -- > dropAround isSpace strip :: JSString -> JSString strip = dropAround isSpace {-# INLINE [1] strip #-} -- | /O(n)/ 'splitAt' @n t@ returns a pair whose first element is a -- prefix of @t@ of length @n@, and whose second is the remainder of -- the string. It is equivalent to @('take' n t, 'drop' n t)@. splitAt :: Int -> JSString -> (JSString, JSString) splitAt (I# n) x = case js_splitAt n x of (# y, z #) -> (y, z) {-# INLINE splitAt #-} -- | /O(n)/ 'span', applied to a predicate @p@ and text @t@, returns -- a pair whose first element is the longest prefix (possibly empty) -- of @t@ of elements that satisfy @p@, and whose second is the -- remainder of the list. span :: (Char -> Bool) -> JSString -> (JSString, JSString) span p x = case js_length x of 0# -> (empty, empty) l -> let c0 = js_uncheckedIndex 0# x in if p (C# (chr# c0)) then loop 0# l else (empty, x) where loop i l | isTrue# (i >=# l) = (x, empty) | otherwise = let c = js_uncheckedIndex i x in if p (C# (chr# c)) then loop (i +# charWidth c) l else (js_substr 0# i x, js_substr1 i x) {-# INLINE span #-} -- | /O(n)/ 'break' is like 'span', but the prefix returned is -- over elements that fail the predicate @p@. break :: (Char -> Bool) -> JSString -> (JSString, JSString) break p = span (not . p) {-# INLINE break #-} -- | /O(n)/ Group characters in a string according to a predicate. groupBy :: (Char -> Char -> Bool) -> JSString -> [JSString] groupBy p x = case js_length x of 0# -> [] l -> let c0 = js_uncheckedIndex 0# x in loop (C# (chr# c0)) 0# (charWidth c0) l where loop b s i l | isTrue# (i >=# l) = if isTrue# (i ># s) then [js_substr1 s x] else [] | otherwise = let c = js_uncheckedIndex i x c' = C# (chr# c) i' = i +# charWidth c in if p b c' then loop b s i' l else js_substring s i x : loop c' i i' l {- -- | Returns the /array/ index (in units of 'Word16') at which a -- character may be found. This is /not/ the same as the logical -- index returned by e.g. 'findIndex'. findAIndexOrEnd :: (Char -> Bool) -> JSString -> Int findAIndexOrEnd q t@(Text _arr _off len) = go 0 where go !i | i >= len || q c = i | otherwise = go (i+d) where Iter c d = iter t i -} -- | /O(n)/ Group characters in a string by equality. group :: JSString -> [JSString] group x = group' x -- fixme, implement lazier version {-# INLINE group #-} group' :: JSString -> [JSString] group' x = unsafeCoerce (js_group x) {-# INLINE group' #-} -- | /O(n^2)/ Return all initial segments of the given 'JSString', shortest -- first. inits :: JSString -> [JSString] inits x = empty : case js_length x of 0# -> [] l -> loop (js_charWidthAt 0# x) l where loop i l | isTrue# (i >=# l) = [x] | otherwise = js_substr 0# i x : loop (i +# js_charWidthAt i x) l -- | /O(n^2)/ Return all final segments of the given 'JSString', longest -- first. tails :: JSString -> [JSString] tails x = case js_length x of -- this could be less strict 0# -> [empty] l -> loop 0# l where loop i l | isTrue# (i >=# l) = [empty] | otherwise = js_substr1 i x : loop (i +# js_charWidthAt i x) l -- $split -- -- Splitting functions in this library do not perform character-wise -- copies to create substrings; they just construct new 'JSString's that -- are slices of the original. -- | /O(m+n)/ Break a 'JSString' into pieces separated by the first 'JSString' -- argument (which cannot be empty), consuming the delimiter. An empty -- delimiter is invalid, and will cause an error to be raised. -- -- Examples: -- -- >>> splitOn "\r\n" "a\r\nb\r\nd\r\ne" -- ["a","b","d","e"] -- -- >>> splitOn "aaa" "aaaXaaaXaaaXaaa" -- ["","X","X","X",""] -- -- >>> splitOn "x" "x" -- ["",""] -- -- and -- -- > intercalate s . splitOn s == id -- > splitOn (singleton c) == split (==c) -- -- (Note: the string @s@ to split on above cannot be empty.) -- -- In (unlikely) bad cases, this function's time complexity degrades -- towards /O(n*m)/. splitOn :: JSString -- ^ String to split on. If this string is empty, an error -- will occur. -> JSString -- ^ Input text. -> [JSString] splitOn = splitOn' -- fixme {- splitOn pat src | null pat = emptyError "splitOn" | otherwise = go 0# where go i = case js_splitOn1 i pat src of (# n, h #) -> case n of -1# -> [] n' -> h : go n' -} {-# INLINE [1] splitOn #-} -- RULES -- "JSSTRING splitOn/singleton -> split/==" [~1] forall c t. -- splitOn (singleton c) t = split (==c) t -- splitOn' :: JSString -- ^ String to split on. If this string is empty, an error -- will occur. -> JSString -- ^ Input text. -> [JSString] splitOn' pat src | null pat = emptyError "splitOn'" | otherwise = unsafeCoerce (js_splitOn pat src) {-# NOINLINE splitOn' #-} --- {-# INLINE [1] splitOn' #-} -- | /O(n)/ Splits a 'JSString' into components delimited by separators, -- where the predicate returns True for a separator element. The -- resulting components do not contain the separators. Two adjacent -- separators result in an empty component in the output. eg. -- -- >>> split (=='a') "aabbaca" -- ["","","bb","c",""] -- -- >>> split (=='a') "" -- [""] split :: (Char -> Bool) -> JSString -> [JSString] split p x = case js_length x of 0# -> [empty] l -> loop 0# 0# l where loop s i l | isTrue# (i >=# l) = [js_substr s i x] | otherwise = let ch = js_uncheckedIndex i x i' = i +# charWidth ch in if p (C# (chr# ch)) then js_substr s (i -# s) x : loop i' i' l else loop s i' l {-# INLINE split #-} -- | /O(n)/ Splits a 'JSString' into components of length @k@. The last -- element may be shorter than the other chunks, depending on the -- length of the input. Examples: -- -- >>> chunksOf 3 "foobarbaz" -- ["foo","bar","baz"] -- -- >>> chunksOf 4 "haskell.org" -- ["hask","ell.","org"] chunksOf :: Int -> JSString -> [JSString] chunksOf (I# k) p = go 0# where go i = case js_chunksOf1 k i p of (# n, c #) -> case n of -1# -> [] _ -> c : go n {-# INLINE chunksOf #-} -- | /O(n)/ Splits a 'JSString' into components of length @k@. The last -- element may be shorter than the other chunks, depending on the -- length of the input. Examples: -- -- > chunksOf 3 "foobarbaz" == ["foo","bar","baz"] -- > chunksOf 4 "haskell.org" == ["hask","ell.","org"] chunksOf' :: Int -> JSString -> [JSString] chunksOf' (I# k) p = unsafeCoerce (js_chunksOf k p) {-# INLINE chunksOf' #-} -- ---------------------------------------------------------------------------- -- * Searching ------------------------------------------------------------------------------- -- ** Searching with a predicate -- | /O(n)/ The 'find' function takes a predicate and a 'JSString', and -- returns the first element matching the predicate, or 'Nothing' if -- there is no such element. find :: (Char -> Bool) -> JSString -> Maybe Char find p t = S.findBy p (stream t) {-# INLINE find #-} -- | /O(n)/ The 'partition' function takes a predicate and a 'JSString', -- and returns the pair of 'JSString's with elements which do and do not -- satisfy the predicate, respectively; i.e. -- -- > partition p t == (filter p t, filter (not . p) t) partition :: (Char -> Bool) -> JSString -> (JSString, JSString) partition p t = (filter p t, filter (not . p) t) {-# INLINE partition #-} -- | /O(n)/ 'filter', applied to a predicate and a 'JSString', -- returns a 'JSString' containing those characters that satisfy the -- predicate. filter :: (Char -> Bool) -> JSString -> JSString filter p t = unstream (S.filter p (stream t)) {-# INLINE filter #-} -- | /O(n+m)/ Find the first instance of @needle@ (which must be -- non-'null') in @haystack@. The first element of the returned tuple -- is the prefix of @haystack@ before @needle@ is matched. The second -- is the remainder of @haystack@, starting with the match. -- -- Examples: -- -- >>> breakOn "::" "a::b::c" -- ("a","::b::c") -- -- >>> breakOn "/" "foobar" -- ("foobar","") -- -- Laws: -- -- > append prefix match == haystack -- > where (prefix, match) = breakOn needle haystack -- -- If you need to break a string by a substring repeatedly (e.g. you -- want to break on every instance of a substring), use 'breakOnAll' -- instead, as it has lower startup overhead. -- -- In (unlikely) bad cases, this function's time complexity degrades -- towards /O(n*m)/. breakOn :: JSString -> JSString -> (JSString, JSString) breakOn pat src | null pat = emptyError "breakOn" | otherwise = case js_breakOn pat src of (# y, z #) -> (y, z) {-# INLINE breakOn #-} -- | /O(n+m)/ Similar to 'breakOn', but searches from the end of the -- string. -- -- The first element of the returned tuple is the prefix of @haystack@ -- up to and including the last match of @needle@. The second is the -- remainder of @haystack@, following the match. -- -- >>> breakOnEnd "::" "a::b::c" -- ("a::b::","c") breakOnEnd :: JSString -> JSString -> (JSString, JSString) breakOnEnd pat src | null pat = emptyError "breakOnEnd" | otherwise = case js_breakOnEnd pat src of (# y, z #) -> (y, z) {-# INLINE breakOnEnd #-} -- | /O(n+m)/ Find all non-overlapping instances of @needle@ in -- @haystack@. Each element of the returned list consists of a pair: -- -- * The entire string prior to the /k/th match (i.e. the prefix) -- -- * The /k/th match, followed by the remainder of the string -- -- Examples: -- -- >>> breakOnAll "::" "" -- [] -- -- >>> breakOnAll "/" "a/b/c/" -- [("a","/b/c/"),("a/b","/c/"),("a/b/c","/")] -- -- In (unlikely) bad cases, this function's time complexity degrades -- towards /O(n*m)/. -- -- The @needle@ parameter may not be empty. breakOnAll :: JSString -- ^ @needle@ to search for -> JSString -- ^ @haystack@ in which to search -> [(JSString, JSString)] breakOnAll pat src | null pat = emptyError "breakOnAll" | otherwise = go 0# where go i = case js_breakOnAll1 i pat src of (# n, x, y #) -> case n of -1# -> [] _ -> (x,y) : go n {-# INLINE breakOnAll #-} breakOnAll' :: JSString -- ^ @needle@ to search for -> JSString -- ^ @haystack@ in which to search -> [(JSString, JSString)] breakOnAll' pat src | null pat = emptyError "breakOnAll'" | otherwise = unsafeCoerce (js_breakOnAll pat src) {-# INLINE breakOnAll' #-} ------------------------------------------------------------------------------- -- ** Indexing 'JSString's -- $index -- -- If you think of a 'JSString' value as an array of 'Char' values (which -- it is not), you run the risk of writing inefficient code. -- -- An idiom that is common in some languages is to find the numeric -- offset of a character or substring, then use that number to split -- or trim the searched string. With a 'JSString' value, this approach -- would require two /O(n)/ operations: one to perform the search, and -- one to operate from wherever the search ended. -- -- For example, suppose you have a string that you want to split on -- the substring @\"::\"@, such as @\"foo::bar::quux\"@. Instead of -- searching for the index of @\"::\"@ and taking the substrings -- before and after that index, you would instead use @breakOnAll \"::\"@. -- | /O(n)/ 'JSString' index (subscript) operator, starting from 0. index :: JSString -> Int -> Char index t n = S.index (stream t) n {-# INLINE index #-} -- | /O(n)/ The 'findIndex' function takes a predicate and a 'JSString' -- and returns the index of the first element in the 'JSString' satisfying -- the predicate. Subject to fusion. findIndex :: (Char -> Bool) -> JSString -> Maybe Int findIndex p t = S.findIndex p (stream t) {-# INLINE findIndex #-} -- | /O(n+m)/ The 'count' function returns the number of times the -- query string appears in the given 'JSString'. An empty query string is -- invalid, and will cause an error to be raised. -- -- In (unlikely) bad cases, this function's time complexity degrades -- towards /O(n*m)/. count :: JSString -> JSString -> Int count pat src | null pat = emptyError "count" | otherwise = I# (js_count pat src) {-# INLINE [1] count #-} -- RULES -- "JSSTRING count/singleton -> countChar" [~1] forall c t. -- count (singleton c) t = countChar c t -- -- | /O(n)/ The 'countChar' function returns the number of times the -- query element appears in the given 'JSString'. Subject to fusion. countChar :: Char -> JSString -> Int countChar c t = S.countChar c (stream t) {-# INLINE countChar #-} ------------------------------------------------------------------------------- -- * Zipping -- | /O(n)/ 'zip' takes two 'JSString's and returns a list of -- corresponding pairs of bytes. If one input 'JSString' is short, -- excess elements of the longer 'JSString' are discarded. This is -- equivalent to a pair of 'unpack' operations. zip :: JSString -> JSString -> [(Char,Char)] zip a b = S.unstreamList $ S.zipWith (,) (stream a) (stream b) {-# INLINE zip #-} -- | /O(n)/ 'zipWith' generalises 'zip' by zipping with the function -- given as the first argument, instead of a tupling function. -- Performs replacement on invalid scalar values. zipWith :: (Char -> Char -> Char) -> JSString -> JSString -> JSString zipWith f t1 t2 = unstream (S.zipWith g (stream t1) (stream t2)) where g a b = safe (f a b) {-# INLINE zipWith #-} -- | /O(n)/ Breaks a 'JSString' up into a list of words, delimited by 'Char's -- representing white space. words :: JSString -> [JSString] words x = loop 0# -- js_words x {- t@(Text arr off len) = loop 0 0 where loop i = case js_words1 i x of (# n, w #) -> case n of -1# -> [] _ -> w : loop n {-# INLINE words #-} -- fixme: strict words' that allocates the whole list in one go words' :: JSString -> [JSString] words' x = unsafeCoerce (js_words x) {-# INLINE words' #-} -- | /O(n)/ Breaks a 'JSString' up into a list of 'JSString's at -- newline 'Char's. The resulting strings do not contain newlines. lines :: JSString -> [JSString] lines ps = loop 0# where loop i = case js_lines1 i ps of (# n, l #) -> case n of -1# -> [] _ -> l : loop n {-# INLINE lines #-} lines' :: JSString -> [JSString] lines' ps = unsafeCoerce (js_lines ps) {-# INLINE lines' #-} {- -- | /O(n)/ Portably breaks a 'JSString' up into a list of 'JSString's at line -- boundaries. -- -- A line boundary is considered to be either a line feed, a carriage -- return immediately followed by a line feed, or a carriage return. -- This accounts for both Unix and Windows line ending conventions, -- and for the old convention used on Mac OS 9 and earlier. lines' :: Text -> [Text] lines' ps | null ps = [] | otherwise = h : case uncons t of Nothing -> [] Just (c,t') | c == '\n' -> lines t' | c == '\r' -> case uncons t' of Just ('\n',t'') -> lines t'' _ -> lines t' where (h,t) = span notEOL ps notEOL c = c /= '\n' && c /= '\r' -} -- | /O(n)/ Joins lines, after appending a terminating newline to -- each. unlines :: [JSString] -> JSString unlines xs = rnf xs `seq` js_unlines (unsafeCoerce xs) {-# INLINE unlines #-} -- | /O(n)/ Joins words using single space characters. unwords :: [JSString] -> JSString unwords xs = rnf xs `seq` js_unwords (unsafeCoerce xs) {-# INLINE unwords #-} -- | /O(n)/ The 'isPrefixOf' function takes two 'JSString's and returns -- 'True' iff the first is a prefix of the second. Subject to fusion. isPrefixOf :: JSString -> JSString -> Bool isPrefixOf x y = js_isPrefixOf x y {-# INLINE [1] isPrefixOf #-} {-# RULES "JSSTRING isPrefixOf -> fused" [~1] forall x y. isPrefixOf x y = S.isPrefixOf (stream x) (stream y) "JSSTRING isPrefixOf -> unfused" [1] forall x y. S.isPrefixOf (stream x) (stream y) = isPrefixOf x y #-} -- | /O(n)/ The 'isSuffixOf' function takes two 'JSString's and returns -- 'True' iff the first is a suffix of the second. isSuffixOf :: JSString -> JSString -> Bool isSuffixOf x y = js_isSuffixOf x y {-# INLINE isSuffixOf #-} -- | The 'isInfixOf' function takes two 'JSString's and returns -- 'True' iff the first is contained, wholly and intact, anywhere -- within the second. -- -- Complexity depends on how the JavaScript engine implements -- String.prototype.find. isInfixOf :: JSString -> JSString -> Bool isInfixOf needle haystack = js_isInfixOf needle haystack {-# INLINE [1] isInfixOf #-} {-# RULES "JSSTRING isInfixOf/singleton -> S.elem/S.stream" [~1] forall n h. isInfixOf (singleton n) h = S.elem n (S.stream h) #-} ------------------------------------------------------------------------------- -- * View patterns -- | /O(n)/ Return the suffix of the second string if its prefix -- matches the entire first string. -- -- Examples: -- -- >>> stripPrefix "foo" "foobar" -- Just "bar" -- -- >>> stripPrefix "" "baz" -- Just "baz" -- -- >>> stripPrefix "foo" "quux" -- Nothing -- -- This is particularly useful with the @ViewPatterns@ extension to -- GHC, as follows: -- -- > {-# LANGUAGE ViewPatterns #-} -- > import Data.Text as T -- > -- > fnordLength :: JSString -> Int -- > fnordLength (stripPrefix "fnord" -> Just suf) = T.length suf -- > fnordLength _ = -1 stripPrefix :: JSString -> JSString -> Maybe JSString stripPrefix x y = unsafeCoerce (js_stripPrefix x y) {-# INLINE stripPrefix #-} -- | /O(n)/ Find the longest non-empty common prefix of two strings -- and return it, along with the suffixes of each string at which they -- no longer match. -- -- If the strings do not have a common prefix or either one is empty, -- this function returns 'Nothing'. -- -- Examples: -- -- >>> commonPrefixes "foobar" "fooquux" -- Just ("foo","bar","quux") -- -- >>> commonPrefixes "veeble" "fetzer" -- Nothing -- -- >>> commonPrefixes "" "baz" -- Nothing commonPrefixes :: JSString -> JSString -> Maybe (JSString,JSString,JSString) commonPrefixes x y = unsafeCoerce (js_commonPrefixes x y) {-# INLINE commonPrefixes #-} -- | /O(n)/ Return the prefix of the second string if its suffix -- matches the entire first string. -- -- Examples: -- -- >>> stripSuffix "bar" "foobar" -- Just "foo" -- -- >>> stripSuffix "" "baz" -- Just "baz" -- -- >>> stripSuffix "foo" "quux" -- Nothing -- -- This is particularly useful with the @ViewPatterns@ extension to -- GHC, as follows: -- -- > {-# LANGUAGE ViewPatterns #-} -- > import Data.Text as T -- > -- > quuxLength :: Text -> Int -- > quuxLength (stripSuffix "quux" -> Just pre) = T.length pre -- > quuxLength _ = -1 stripSuffix :: JSString -> JSString -> Maybe JSString stripSuffix x y = unsafeCoerce (js_stripSuffix x y) {-# INLINE stripSuffix #-} -- | Add a list of non-negative numbers. Errors out on overflow. sumP :: String -> [Int] -> Int sumP fun = go 0 where go !a (x:xs) | ax >= 0 = go ax xs | otherwise = overflowError fun where ax = a + x go a _ = a emptyError :: String -> a emptyError fun = P.error $ "Data.JSString." ++ fun ++ ": empty input" overflowError :: String -> a overflowError fun = P.error $ "Data.JSString." ++ fun ++ ": size overflow" charWidth :: Int# -> Int# charWidth cp | isTrue# (cp >=# 0x10000#) = 2# | otherwise = 1# {-# INLINE charWidth #-} -- ----------------------------------------------------------------------------- foreign import javascript unsafe "h$jsstringPack($1)" js_pack :: Exts.Any -> JSString foreign import javascript unsafe "$1===''" js_null :: JSString -> Bool foreign import javascript unsafe "$1===null" js_isNull :: JSVal -> Bool foreign import javascript unsafe "$1===$2" js_eq :: JSString -> JSString -> Bool foreign import javascript unsafe -- "h$jsstringAppend" js_append :: JSString -> JSString -> JSString -- debug "$1+$2" js_append :: JSString -> JSString -> JSString foreign import javascript unsafe "h$jsstringCompare" js_compare :: JSString -> JSString -> Int# -- "($1<$2)?-1:(($1>$2)?1:0)" js_compare :: JSString -> JSString -> Int# foreign import javascript unsafe "h$jsstringSingleton" js_singleton :: Char -> JSString foreign import javascript unsafe "h$jsstringUnpack" js_unpack :: JSString -> Exts.Any -- String foreign import javascript unsafe "h$jsstringCons" js_cons :: Char -> JSString -> JSString foreign import javascript unsafe "h$jsstringSnoc" js_snoc :: JSString -> Char -> JSString foreign import javascript unsafe "h$jsstringUncons" js_uncons :: JSString -> (# Int#, JSString #) foreign import javascript unsafe "h$jsstringUnsnoc" js_unsnoc :: JSString -> (# Int#, JSString #) foreign import javascript unsafe "$3.substr($1,$2)" js_substr :: Int# -> Int# -> JSString -> JSString foreign import javascript unsafe "$2.substr($1)" js_substr1 :: Int# -> JSString -> JSString foreign import javascript unsafe "$3.substring($1,$2)" js_substring :: Int# -> Int# -> JSString -> JSString foreign import javascript unsafe "$1.length" js_length :: JSString -> Int# foreign import javascript unsafe "(($2.charCodeAt($1)|1023)===0xDBFF)?2:1" js_charWidthAt :: Int# -> JSString -> Int# foreign import javascript unsafe "h$jsstringIndex" js_index :: Int# -> JSString -> Int# foreign import javascript unsafe "h$jsstringIndexR" js_indexR :: Int# -> JSString -> Int# foreign import javascript unsafe "h$jsstringUncheckedIndex" js_uncheckedIndex :: Int# -> JSString -> Int# foreign import javascript unsafe "h$jsstringIndexR" js_uncheckedIndexR :: Int# -> JSString -> Int# -- js_head and js_last return -1 for empty string foreign import javascript unsafe "h$jsstringHead" js_head :: JSString -> Int# foreign import javascript unsafe "h$jsstringLast" js_last :: JSString -> Int# foreign import javascript unsafe "h$jsstringInit" js_init :: JSString -> JSVal -- null for empty string foreign import javascript unsafe "h$jsstringTail" js_tail :: JSString -> JSVal -- null for empty string foreign import javascript unsafe "h$jsstringReverse" js_reverse :: JSString -> JSString foreign import javascript unsafe "h$jsstringGroup" js_group :: JSString -> Exts.Any {- [JSString] -} --foreign import javascript unsafe -- "h$jsstringGroup1" js_group1 -- :: Int# -> Bool -> JSString -> (# Int#, JSString #) foreign import javascript unsafe "h$jsstringConcat" js_concat :: Exts.Any {- [JSString] -} -> JSString -- debug this below! foreign import javascript unsafe "h$jsstringReplace" js_replace :: JSString -> JSString -> JSString -> JSString foreign import javascript unsafe "h$jsstringCount" js_count :: JSString -> JSString -> Int# foreign import javascript unsafe "h$jsstringWords1" js_words1 :: Int# -> JSString -> (# Int#, JSString #) foreign import javascript unsafe "h$jsstringWords" js_words :: JSString -> Exts.Any -- [JSString] foreign import javascript unsafe "h$jsstringLines1" js_lines1 :: Int# -> JSString -> (# Int#, JSString #) foreign import javascript unsafe "h$jsstringLines" js_lines :: JSString -> Exts.Any -- [JSString] foreign import javascript unsafe "h$jsstringUnlines" js_unlines :: Exts.Any {- [JSString] -} -> JSString foreign import javascript unsafe "h$jsstringUnwords" js_unwords :: Exts.Any {- [JSString] -} -> JSString foreign import javascript unsafe "h$jsstringIsPrefixOf" js_isPrefixOf :: JSString -> JSString -> Bool foreign import javascript unsafe "h$jsstringIsSuffixOf" js_isSuffixOf :: JSString -> JSString -> Bool foreign import javascript unsafe "h$jsstringIsInfixOf" js_isInfixOf :: JSString -> JSString -> Bool foreign import javascript unsafe "h$jsstringStripPrefix" js_stripPrefix :: JSString -> JSString -> Exts.Any -- Maybe JSString foreign import javascript unsafe "h$jsstringStripSuffix" js_stripSuffix :: JSString -> JSString -> Exts.Any -- Maybe JSString foreign import javascript unsafe "h$jsstringCommonPrefixes" js_commonPrefixes :: JSString -> JSString -> Exts.Any -- Maybe (JSString, JSString, JSString) foreign import javascript unsafe "h$jsstringChunksOf" js_chunksOf :: Int# -> JSString -> Exts.Any -- [JSString] foreign import javascript unsafe "h$jsstringChunksOf1" js_chunksOf1 :: Int# -> Int# -> JSString -> (# Int#, JSString #) foreign import javascript unsafe "h$jsstringSplitAt" js_splitAt :: Int# -> JSString -> (# JSString, JSString #) foreign import javascript unsafe "h$jsstringSplitOn" js_splitOn :: JSString -> JSString -> Exts.Any -- [JSString] foreign import javascript unsafe "h$jsstringSplitOn1" js_splitOn1 :: Int# -> JSString -> JSString -> (# Int#, JSString #) foreign import javascript unsafe "h$jsstringBreakOn" js_breakOn :: JSString -> JSString -> (# JSString, JSString #) foreign import javascript unsafe "h$jsstringBreakOnEnd" js_breakOnEnd :: JSString -> JSString -> (# JSString, JSString #) foreign import javascript unsafe "h$jsstringBreakOnAll" js_breakOnAll :: JSString -> JSString -> Exts.Any -- [(JSString, JSString)] foreign import javascript unsafe "h$jsstringBreakOnAll1" js_breakOnAll1 :: Int# -> JSString -> JSString -> (# Int#, JSString, JSString #) foreign import javascript unsafe "h$jsstringDrop" js_drop :: Int# -> JSString -> JSString foreign import javascript unsafe "h$jsstringDropEnd" js_dropEnd :: Int -> JSString -> JSString foreign import javascript unsafe "h$jsstringTake" js_take :: Int# -> JSString -> JSString foreign import javascript unsafe "h$jsstringTakeEnd" js_takeEnd :: Int# -> JSString -> JSString foreign import javascript unsafe "h$jsstringReplicate" js_replicate :: Int# -> JSString -> JSString foreign import javascript unsafe "h$jsstringReplicateChar" js_replicateChar :: Int -> Char -> JSString foreign import javascript unsafe "var l=$1.length; $r=l==1||(l==2&&($1.charCodeAt(0)|1023)==0xDFFF);" js_isSingleton :: JSString -> Bool foreign import javascript unsafe "h$jsstringIntersperse" js_intersperse :: Char -> JSString -> JSString foreign import javascript unsafe "h$jsstringIntercalate" js_intercalate :: JSString -> Exts.Any {- [JSString] -} -> JSString foreign import javascript unsafe "$1.toUpperCase()" js_toUpper :: JSString -> JSString foreign import javascript unsafe "$1.toLowerCase()" js_toLower :: JSString -> JSString