content: {-# LANGUAGE MagicHash, BangPatterns, UnboxedTuples, TypeFamilies
    #-}
  {-# OPTIONS_GHC -fno-warn-orphans #-}
  {-| 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
                       , 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
                       , 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.Char                            (isSpace)
  import           Data.Coerce                          (coerce)
  import qualified Data.List                            as L
  import           Data.Data
  import qualified Data.Text                            as T
  import qualified Data.Text.Internal.Fusion            as TF
  import qualified Data.Text.Internal.Fusion.Common     as TF
  
  import           GHC.Exts
    ( Int#, (+#), (-#), (>=#), (>#), isTrue#, chr#, Char(..)
    , Int(..), Addr#, tagToEnum#)
  import qualified GHC.Exts                             as Exts
  import qualified GHC.CString                          as GHC
  
  import           Unsafe.Coerce
  
  import           GHCJS.Prim                           (JSVal)
  
  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
  
  instance Exts.IsList JSString where
    type Item JSString = Char
    fromList           = pack
    toList             = unpack
  
  -- -----------------------------------------------------------------------------
  -- * Conversion to/from 'JSString'
  
  -- | /O(n)/ Convert a 'String' into a 'JSString'.  Subject to
  -- fusion.
  pack :: String -> JSString
  pack = coerce T.pack
  {-# 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' = coerce T.unpack
  {-# INLINE unpack' #-}
  
  -- | /O(n)/ Convert a literal string into a JSString.  Subject to fusion.
  unpackCString# :: Addr# -> JSString
  unpackCString# = coerce T.unpackCString#
  {-# 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 #-}
  
  
  -- | /O(1)/ Convert a character into a 'JSString'.  Subject to fusion.
  -- Performs replacement on invalid scalar values.
  singleton :: Char -> JSString
  singleton = coerce T.singleton
  {-# 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 = coerce T.cons
  {-# 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 = coerce T.snoc
    -- 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 = coerce T.append
  {-# 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 = coerce T.head
  {-# 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 = coerce T.uncons
  {-# INLINE [1] uncons #-}
  
  -- | 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 = coerce T.last
  {-# 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 = coerce T.tail
  {-# 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 = coerce T.init
  {-# 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 = coerce T.null
  {-# 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(n)/ Returns the number of characters in a 'JSString'.
  -- Subject to fusion.
  length :: JSString -> Int
  length = coerce T.length
  {-# INLINE [1] length #-}
  
  {-# RULES
  "JSSTRING length -> fused" [~1] forall x.
      length x = S.length (stream x)
  "JSSTRING length -> unfused" [1] forall x.
      S.length (stream x) = length x
   #-}
  
  -- | /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 = coerce T.compareLength
  {-# 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.
      (==) (length t) n = compareLength t n == EQ
    #-}
  
  {-# RULES
  "JSSTRING /=N/length -> compareLength//=EQ" [~1] forall t n.
      (/=) (length t) n = compareLength t n /= EQ
    #-}
  
  {-# RULES
  "JSSTRING <N/length -> compareLength/==LT" [~1] forall t n.
      (<) (length t) n = compareLength t n == LT
    #-}
  
  {-# RULES
  "JSSTRING <=N/length -> compareLength//=GT" [~1] forall t n.
      (<=) (length t) n = compareLength t n /= GT
    #-}
  
  {-# RULES
  "JSSTRING >N/length -> compareLength/==GT" [~1] forall t n.
      (>) (length t) n = compareLength t n == GT
    #-}
  
  {-# RULES
  "JSSTRING >=N/length -> compareLength//=LT" [~1] forall t n.
      (>=) (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@.  Subject to fusion.  Performs replacement on
  -- invalid scalar values.
  map :: (Char -> Char) -> JSString -> JSString
  map = coerce T.map
  {-# 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 = coerce T.intercalate
  {-# INLINE [1] intercalate #-}
  
  -- | /O(n)/ The 'intersperse' function takes a character and places it
  -- between the characters of a 'JSString'.  Subject to fusion.  Performs
  -- replacement on invalid scalar values.
  intersperse     :: Char -> JSString -> JSString
  intersperse = coerce T.intersperse
  {-# 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. Subject to fusion.
  reverse :: JSString -> JSString
  reverse = coerce T.reverse
  {-# 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 = coerce T.replace
  {-# 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
  -- <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 >.
  
  -- | /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 \"&#xfb13;\" (men now, U+FB13) is case
  -- folded to the sequence \"&#x574;\" (men, U+0574) followed by
  -- \"&#x576;\" (now, U+0576), while the Greek \"&#xb5;\" (micro sign,
  -- U+00B5) is case folded to \"&#x3bc;\" (small letter mu, U+03BC)
  -- instead of itself.
  toCaseFold :: JSString -> JSString
  toCaseFold = coerce T.toCaseFold
  {-# INLINE [0] 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, \"&#x130;\" (Latin capital letter I with dot above,
  -- U+0130) maps to the sequence \"i\" (Latin small letter i, U+0069)
  -- followed by \" &#x307;\" (combining dot above, U+0307).
  toLower :: JSString -> JSString
  toLower = coerce T.toLower
  {-# 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 \"&#xdf;\" (eszett, U+00DF) maps to the
  -- two-letter sequence \"SS\".
  toUpper :: JSString -> JSString
  toUpper = coerce T.toUpper
  {-# 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 &#xfb02; (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&#x2014;but this function will
  -- capitalize /every/ word.
  toTitle :: JSString -> JSString
  toTitle = coerce T.toTitle
  {-# 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 = coerce T.justifyLeft
  {-# 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 = coerce T.justifyRight
  {-# 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 = coerce T.center
  {-# 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.
  transpose :: [JSString] -> [JSString]
  transpose = coerce T.transpose
  
  -- -----------------------------------------------------------------------------
  -- * 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 = coerce (T.foldl f)
  {-# INLINE foldl #-}
  
  -- | /O(n)/ A strict version of 'foldl'.  Subject to fusion.
  foldl' :: (a -> Char -> a) -> a -> JSString -> a
  foldl' f = coerce (T.foldl' f)
  {-# 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 = coerce T.foldl1
  {-# INLINE foldl1 #-}
  
  -- | /O(n)/ A strict version of 'foldl1'.  Subject to fusion.
  foldl1' :: (Char -> Char -> Char) -> JSString -> Char
  foldl1' = coerce T.foldl1'
  {-# 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 = coerce (T.foldr f)
  {-# 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 = coerce T.foldr1
  {-# INLINE foldr1 #-}
  
  -- -----------------------------------------------------------------------------
  -- ** Special folds
  
  -- | /O(n)/ Concatenate a list of 'JSString's.
  concat :: [JSString] -> JSString
  concat = coerce T.concat
  
  -- | /O(n)/ Map a function over a 'JSString' that results in a 'JSString', and
  -- concatenate the results.
  concatMap :: (Char -> JSString) -> JSString -> JSString
  concatMap = coerce T.concatMap
  {-# INLINE concatMap #-}
  
  -- | /O(n)/ 'any' @p@ @t@ determines whether any character in the
  -- 'JSString' @t@ satisifes the predicate @p@. Subject to fusion.
  any :: (Char -> Bool) -> JSString -> Bool
  any = coerce T.any
  {-# 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 = coerce T.all
  {-# INLINE all #-}
  
  -- | /O(n)/ 'maximum' returns the maximum value from a 'JSString', which
  -- must be non-empty. Subject to fusion.
  maximum :: JSString -> Char
  maximum = coerce T.maximum
  {-# INLINE maximum #-}
  
  -- | /O(n)/ 'minimum' returns the minimum value from a 'JSString', which
  -- must be non-empty. Subject to fusion.
  minimum :: JSString -> Char
  minimum = coerce T.minimum
  {-# 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 = coerce T.scanl
  {-# 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 = coerce T.scanl1
  {-# 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 = coerce T.scanr
  {-# 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 = coerce T.scanr1
  {-# 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 = coerce (T.mapAccumL f)
  {-# 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 = coerce (T.mapAccumR f)
  {-# 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 = coerce T.replicate
  {-# INLINE [1] replicate #-}
  
  -- | /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 = coerce (T.unfoldr f)
  {-# 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 = coerce (T.unfoldrN n f)
  {-# 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 = coerce T.take
  {-# 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 = coerce T.takeEnd
  
  -- | /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 = coerce T.drop
  {-# 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 = coerce T.dropEnd
  
  -- | /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 = coerce T.takeWhile
  {-# 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)/ 'dropWhile' @p@ @t@ returns the suffix remaining after
  -- 'takeWhile' @p@ @t@. Subject to fusion.
  dropWhile :: (Char -> Bool) -> JSString -> JSString
  dropWhile = coerce T.dropWhile
  {-# 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 fail the predicate @p@ from the end of
  -- @t@.  Subject to fusion.
  -- Examples:
  --
  -- > dropWhileEnd (=='.') "foo..." == "foo"
  dropWhileEnd :: (Char -> Bool) -> JSString -> JSString
  dropWhileEnd = coerce T.dropWhileEnd
  {-# 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 fail the predicate @p@ from both the
  -- beginning and end of @t@.  Subject to fusion.
  dropAround :: (Char -> Bool) -> JSString -> JSString
  dropAround = coerce T.dropAround
  {-# INLINE [1] dropAround #-}
  
  -- | /O(n)/ Remove leading white space from a string.  Equivalent to:
  --
  -- > dropWhile isSpace
  stripStart :: JSString -> JSString
  stripStart = coerce T.stripStart
  {-# INLINE [1] stripStart #-}
  
  -- | /O(n)/ Remove trailing white space from a string.  Equivalent to:
  --
  -- > dropWhileEnd isSpace
  stripEnd :: JSString -> JSString
  stripEnd = coerce T.stripEnd
  {-# INLINE [1] stripEnd #-}
  
  -- | /O(n)/ Remove leading and trailing white space from a string.
  -- Equivalent to:
  --
  -- > dropAround isSpace
  strip :: JSString -> JSString
  strip = coerce T.strip
  {-# 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 = coerce T.splitAt
  {-# 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 = coerce T.span
  {-# 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 = coerce T.break
  {-# INLINE break #-}
  
  -- | /O(n)/ Group characters in a string according to a predicate.
  groupBy :: (Char -> Char -> Bool) -> JSString -> [JSString]
  groupBy = coerce T.groupBy
  
  -- | /O(n)/ Group characters in a string by equality.
  group :: JSString -> [JSString]
  group = coerce T.group
  {-# INLINE group #-}
  
  group' :: JSString -> [JSString]
  group' = coerce T.group
  {-# INLINE group' #-}
  
  -- | /O(n^2)/ Return all initial segments of the given 'JSString', shortest
  -- first.
  inits :: JSString -> [JSString]
  inits = coerce T.inits
  
  -- | /O(n^2)/ Return all final segments of the given 'JSString', longest
  -- first.
  tails :: JSString -> [JSString]
  tails = coerce T.tails
  
  -- $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 = coerce T.splitOn
  {-# 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' = coerce T.splitOn
  {-# 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 = coerce T.split
  {-# 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 = coerce T.chunksOf
  {-# 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' = coerce T.chunksOf
  {-# 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 = coerce T.find
  {-# 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 = coerce T.partition
  {-# 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 = coerce T.filter
  {-# 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 = coerce T.breakOn
  {-# 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 = coerce T.breakOnEnd
  {-# 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 = coerce T.breakOnAll
  {-# INLINE breakOnAll #-}
  
  breakOnAll' :: JSString              -- ^ @needle@ to search for
              -> JSString              -- ^ @haystack@ in which to search
              -> [(JSString, JSString)]
  breakOnAll' = coerce T.breakOnAll
  {-# 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 = coerce T.index
  {-# 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 = coerce T.findIndex
  {-# 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 = coerce T.count
  {-# INLINE [1] count #-}
  
  --  RULES
  -- "JSSTRING count/singleton -> countChar" [~1] forall c t.
  --    count (singleton c) t = countChar c t
  --
  
  -------------------------------------------------------------------------------
  -- * 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 = coerce T.zip
  {-# INLINE [0] 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 = coerce T.zipWith
  {-# INLINE [0] zipWith #-}
  
  -- | /O(n)/ Breaks a 'JSString' up into a list of words, delimited by 'Char's
  -- representing white space.
  words :: JSString -> [JSString]
  words = coerce T.words
  {-# INLINE words #-}
  
  -- fixme: strict words' that allocates the whole list in one go
  words' :: JSString -> [JSString]
  words' = coerce T.words
  {-# 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 = coerce T.lines
  {-# INLINE lines #-}
  
  lines' :: JSString -> [JSString]
  lines' = coerce T.lines
  {-# 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 = coerce T.unlines
  {-# INLINE unlines #-}
  
  -- | /O(n)/ Joins words using single space characters.
  unwords :: [JSString] -> JSString
  unwords = coerce T.unwords
  {-# 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 = coerce T.isPrefixOf
  {-# 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 = coerce T.isSuffixOf
  {-# 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 = coerce T.isInfixOf
  {-# 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 = coerce T.stripPrefix
  {-# 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 = coerce T.commonPrefixes
  {-# 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 = coerce T.stripSuffix
  {-# 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 #-}
  