foundation-0.0.12: Foundation/String/UTF8.hs
-- |
-- Module : Foundation.String.UTF8
-- License : BSD-style
-- Maintainer : Vincent Hanquez <vincent@snarc.org>
-- Stability : experimental
-- Portability : portable
--
-- A String type backed by a UTF8 encoded byte array and all the necessary
-- functions to manipulate the string.
--
-- You can think of String as a specialization of a byte array that
-- have element of type Char.
--
-- The String data must contain UTF8 valid data.
--
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE MagicHash #-}
{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE UnboxedTuples #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE CPP #-}
module Foundation.String.UTF8
( String(..)
, MutableString(..)
, create
, replicate
, length
-- * Binary conversion
, Encoding(..)
, fromBytes
, fromChunkBytes
, fromBytesUnsafe
, fromBytesLenient
, toBytes
, mutableValidate
, copy
, ValidationFailure(..)
, index
, null
, drop
, take
, splitAt
, revDrop
, revTake
, revSplitAt
, splitOn
, sub
, elem
, indices
, intersperse
, span
, break
, breakElem
, dropWhile
, singleton
, charMap
, snoc
, cons
, unsnoc
, uncons
, find
, findIndex
, sortBy
, filter
, reverse
, replace
, builderAppend
, builderBuild
, builderBuild_
, readInteger
, readIntegral
, readNatural
, readDouble
, readRational
, readFloatingExact
, upper
, lower
, isPrefixOf
, isSuffixOf
, isInfixOf
-- * Legacy utility
, lines
, words
, toBase64
, toBase64URL
, toBase64OpenBSD
) where
import Foundation.Array.Unboxed (UArray)
import qualified Foundation.Array.Unboxed as Vec
import qualified Foundation.Array.Unboxed as C
import Foundation.Array.Unboxed.ByteArray (MutableByteArray)
import qualified Foundation.Array.Unboxed.Mutable as MVec
import Foundation.Class.Bifunctor
import Foundation.Internal.Base
import Foundation.Internal.Natural
import Foundation.Internal.MonadTrans
import Foundation.Internal.Primitive
import Foundation.Primitive.Types.OffsetSize
import Foundation.Numerical
import Foundation.Primitive.Monad
import Foundation.Primitive.Types
import Foundation.Primitive.FinalPtr
import Foundation.Primitive.IntegralConv
import Foundation.Primitive.Floating
import Foundation.Boot.Builder
import Foundation.Primitive.UTF8.Table
import Foundation.Primitive.UTF8.Helper
import Foundation.Primitive.UTF8.Base
import qualified Foundation.Primitive.UTF8.BA as PrimBA
import qualified Foundation.Primitive.UTF8.Addr as PrimAddr
import qualified Foundation.String.UTF8.BA as BackendBA
import qualified Foundation.String.UTF8.Addr as BackendAddr
import GHC.Prim
import GHC.ST
import GHC.Types
import GHC.Word
#if MIN_VERSION_base(4,9,0)
import GHC.Char
#endif
-- temporary
import qualified Data.List
import Data.Ratio
import Data.Char (toUpper, toLower)
import qualified Prelude
import qualified Foundation.String.Encoding.Encoding as Encoder
import qualified Foundation.String.Encoding.ASCII7 as Encoder
import qualified Foundation.String.Encoding.UTF16 as Encoder
import qualified Foundation.String.Encoding.UTF32 as Encoder
import qualified Foundation.String.Encoding.ISO_8859_1 as Encoder
-- | UTF8 Encoder
data EncoderUTF8 = EncoderUTF8
instance Encoder.Encoding EncoderUTF8 where
type Unit EncoderUTF8 = Word8
type Error EncoderUTF8 = ValidationFailure
encodingNext _ = \ofs -> Right . nextWithIndexer ofs
encodingWrite _ = writeWithBuilder
-- | Validate a bytearray for UTF8'ness
--
-- On success Nothing is returned
-- On Failure the position along with the failure reason
validate :: UArray Word8
-> Offset8
-> CountOf Word8
-> (Offset8, Maybe ValidationFailure)
validate array ofsStart sz = C.unsafeDewrap goBa goAddr array
where
unTranslateOffset start = first (\e -> e `offsetSub` start)
goBa ba start =
unTranslateOffset start $ BackendBA.validate (start+end) ba (start + ofsStart)
goAddr (Ptr addr) start =
pure $ unTranslateOffset start $ BackendAddr.validate (start+end) addr (ofsStart + start)
end = ofsStart `offsetPlusE` sz
-- | Similar to 'validate' but works on a 'MutableByteArray'
mutableValidate :: PrimMonad prim
=> MutableByteArray (PrimState prim)
-> Offset Word8
-> CountOf Word8
-> prim (Offset Word8, Maybe ValidationFailure)
mutableValidate mba ofsStart sz = do
loop ofsStart
where
end = ofsStart `offsetPlusE` sz
loop ofs
| ofs > end = error "mutableValidate: internal error: went pass offset"
| ofs == end = return (end, Nothing)
| otherwise = do
r <- one ofs
case r of
(nextOfs, Nothing) -> loop nextOfs
(pos, Just failure) -> return (pos, Just failure)
one pos = do
h <- Vec.unsafeRead mba pos
let nbConts = getNbBytes h
if nbConts == 0xff
then return (pos, Just InvalidHeader)
else if pos + 1 + Offset nbConts > end
then return (pos, Just MissingByte)
else do
case nbConts of
0 -> return (pos + 1, Nothing)
1 -> do
c1 <- Vec.unsafeRead mba (pos + 1)
if isContinuation c1
then return (pos + 2, Nothing)
else return (pos, Just InvalidContinuation)
2 -> do
c1 <- Vec.unsafeRead mba (pos + 1)
c2 <- Vec.unsafeRead mba (pos + 2)
if isContinuation c1 && isContinuation c2
then return (pos + 3, Nothing)
else return (pos, Just InvalidContinuation)
3 -> do
c1 <- Vec.unsafeRead mba (pos + 1)
c2 <- Vec.unsafeRead mba (pos + 2)
c3 <- Vec.unsafeRead mba (pos + 3)
if isContinuation c1 && isContinuation c2 && isContinuation c3
then return (pos + 4, Nothing)
else return (pos, Just InvalidContinuation)
_ -> error "internal error"
nextWithIndexer :: (Offset Word8 -> Word8)
-> Offset Word8
-> (Char, Offset Word8)
nextWithIndexer getter off =
case getNbBytes# h of
0# -> (toChar h, off + 1)
1# -> (toChar (decode2 (getter $ off + 1)), off + 2)
2# -> (toChar (decode3 (getter $ off + 1) (getter $ off + 2)), off + 3)
3# -> (toChar (decode4 (getter $ off + 1) (getter $ off + 2) (getter $ off + 3))
, off + 4)
r -> error ("next: internal error: invalid input: " <> show (I# r) <> " " <> show (W# h))
where
!(W8# h) = getter off
toChar :: Word# -> Char
toChar w = C# (chr# (word2Int# w))
decode2 :: Word8 -> Word#
decode2 (W8# c1) =
or# (uncheckedShiftL# (and# h 0x1f##) 6#)
(and# c1 0x3f##)
decode3 :: Word8 -> Word8 -> Word#
decode3 (W8# c1) (W8# c2) =
or# (uncheckedShiftL# (and# h 0xf##) 12#)
(or# (uncheckedShiftL# (and# c1 0x3f##) 6#)
(and# c2 0x3f##))
decode4 :: Word8 -> Word8 -> Word8 -> Word#
decode4 (W8# c1) (W8# c2) (W8# c3) =
or# (uncheckedShiftL# (and# h 0x7##) 18#)
(or# (uncheckedShiftL# (and# c1 0x3f##) 12#)
(or# (uncheckedShiftL# (and# c2 0x3f##) 6#)
(and# c3 0x3f##))
)
writeWithBuilder :: (PrimMonad st, Monad st)
=> Char
-> Builder (UArray Word8) (MVec.MUArray Word8) Word8 st err ()
writeWithBuilder c
| bool# (ltWord# x 0x80## ) = encode1
| bool# (ltWord# x 0x800## ) = encode2
| bool# (ltWord# x 0x10000##) = encode3
| otherwise = encode4
where
!(I# xi) = fromEnum c
!x = int2Word# xi
encode1 = Vec.builderAppend (W8# x)
encode2 = do
let x1 = or# (uncheckedShiftRL# x 6#) 0xc0##
x2 = toContinuation x
Vec.builderAppend (W8# x1) >> Vec.builderAppend (W8# x2)
encode3 = do
let x1 = or# (uncheckedShiftRL# x 12#) 0xe0##
x2 = toContinuation (uncheckedShiftRL# x 6#)
x3 = toContinuation x
Vec.builderAppend (W8# x1) >> Vec.builderAppend (W8# x2) >> Vec.builderAppend (W8# x3)
encode4 = do
let x1 = or# (uncheckedShiftRL# x 18#) 0xf0##
x2 = toContinuation (uncheckedShiftRL# x 12#)
x3 = toContinuation (uncheckedShiftRL# x 6#)
x4 = toContinuation x
Vec.builderAppend (W8# x1) >> Vec.builderAppend (W8# x2) >> Vec.builderAppend (W8# x3) >> Vec.builderAppend (W8# x4)
toContinuation :: Word# -> Word#
toContinuation w = or# (and# w 0x3f##) 0x80##
writeUTF8Char :: PrimMonad prim => MutableString (PrimState prim) -> Offset8 -> UTF8Char -> prim ()
writeUTF8Char (MutableString mba) i (UTF8_1 x1) =
Vec.unsafeWrite mba i x1
writeUTF8Char (MutableString mba) i (UTF8_2 x1 x2) = do
Vec.unsafeWrite mba i x1
Vec.unsafeWrite mba (i+1) x2
writeUTF8Char (MutableString mba) i (UTF8_3 x1 x2 x3) = do
Vec.unsafeWrite mba i x1
Vec.unsafeWrite mba (i+1) x2
Vec.unsafeWrite mba (i+2) x3
writeUTF8Char (MutableString mba) i (UTF8_4 x1 x2 x3 x4) = do
Vec.unsafeWrite mba i x1
Vec.unsafeWrite mba (i+1) x2
Vec.unsafeWrite mba (i+2) x3
Vec.unsafeWrite mba (i+3) x4
{-# INLINE writeUTF8Char #-}
unsafeFreezeShrink :: PrimMonad prim => MutableString (PrimState prim) -> CountOf Word8 -> prim String
unsafeFreezeShrink (MutableString mba) s = String <$> Vec.unsafeFreezeShrink mba s
{-# INLINE unsafeFreezeShrink #-}
------------------------------------------------------------------------
-- real functions
-- | Check if a String is null
null :: String -> Bool
null (String ba) = C.length ba == 0
-- we don't know in constant time the count of character in string,
-- however if we estimate bounds of what N characters would
-- take in space (between N and N*4). If the count is thus bigger than
-- the number of bytes, then we know for sure that it's going to
-- be out of bounds
countCharMoreThanBytes :: CountOf Char -> UArray Word8 -> Bool
countCharMoreThanBytes (CountOf chars) ba = chars >= bytes
where (CountOf bytes) = C.length ba
-- | Create a string composed of a number @n of Chars (Unicode code points).
--
-- if the input @s contains less characters than required, then the input string is returned.
take :: CountOf Char -> String -> String
take n s@(String ba)
| n <= 0 = mempty
| countCharMoreThanBytes n ba = s
| otherwise = String $ Vec.unsafeTake (offsetAsSize $ indexN n s) ba
-- | Create a string with the remaining Chars after dropping @n Chars from the beginning
drop :: CountOf Char -> String -> String
drop n s@(String ba)
| n <= 0 = s
| countCharMoreThanBytes n ba = mempty
| otherwise = String $ Vec.drop (offsetAsSize $ indexN n s) ba
-- | Split a string at the Offset specified (in Char) returning both
-- the leading part and the remaining part.
splitAt :: CountOf Char -> String -> (String, String)
splitAt n s@(String ba)
| n <= 0 = (mempty, s)
| countCharMoreThanBytes n ba = (s, mempty)
| otherwise =
let (v1,v2) = C.splitAt (offsetAsSize $ indexN n s) ba
in (String v1, String v2)
-- | Return the offset (in bytes) of the N'th sequence in an UTF8 String
indexN :: CountOf Char -> String -> Offset Word8
indexN !n (String ba) = Vec.unsafeDewrap goVec goAddr ba
where
goVec :: ByteArray# -> Offset Word8 -> Offset Word8
goVec !ma !start = loop start 0
where
!len = start `offsetPlusE` Vec.length ba
loop :: Offset Word8 -> Offset Char -> Offset Word8
loop !idx !i
| idx >= len || i .==# n = sizeAsOffset (idx - start)
| otherwise = loop (idx `offsetPlusE` d) (i + Offset 1)
where d = skipNextHeaderValue (primBaIndex ma idx)
{-# INLINE goVec #-}
goAddr :: Ptr Word8 -> Offset Word8 -> ST s (Offset Word8)
goAddr (Ptr ptr) !start = return $ loop start (Offset 0)
where
!len = start `offsetPlusE` Vec.length ba
loop :: Offset Word8 -> Offset Char -> Offset Word8
loop !idx !i
| idx >= len || i .==# n = sizeAsOffset (idx - start)
| otherwise = loop (idx `offsetPlusE` d) (i + Offset 1)
where d = skipNextHeaderValue (primAddrIndex ptr idx)
{-# INLINE goAddr #-}
{-# INLINE indexN #-}
-- inverse a CountOf that is specified from the end (e.g. take n Chars from the end)
--
-- rev{Take,Drop,SplitAt} TODO optimise:
-- we can process the string from the end using a skipPrev instead of getting the length
countFromStart :: String -> CountOf Char -> CountOf Char
countFromStart s sz@(CountOf sz')
| sz >= len = CountOf 0
| otherwise = CountOf (len' - sz')
where len@(CountOf len') = length s
-- | Similar to 'take' but from the end
revTake :: CountOf Char -> String -> String
revTake n v = drop (countFromStart v n) v
-- | Similar to 'drop' but from the end
revDrop :: CountOf Char -> String -> String
revDrop n v = take (countFromStart v n) v
-- | Similar to 'splitAt' but from the end
revSplitAt :: CountOf Char -> String -> (String, String)
revSplitAt n v = (drop idx v, take idx v) where idx = countFromStart v n
-- | Split on the input string using the predicate as separator
--
-- e.g.
--
-- > splitOn (== ',') "," == ["",""]
-- > splitOn (== ',') ",abc," == ["","abc",""]
-- > splitOn (== ':') "abc" == ["abc"]
-- > splitOn (== ':') "abc::def" == ["abc","","def"]
-- > splitOn (== ':') "::abc::def" == ["","","abc","","def"]
--
splitOn :: (Char -> Bool) -> String -> [String]
splitOn predicate s
| sz == CountOf 0 = [mempty]
| otherwise = loop azero azero
where
!sz = size s
end = azero `offsetPlusE` sz
loop prevIdx idx
| idx == end = [sub s prevIdx idx]
| otherwise =
let (# c, idx' #) = next s idx
in if predicate c
then sub s prevIdx idx : loop idx' idx'
else loop prevIdx idx'
-- | Internal call to make a substring given offset in bytes.
--
-- This is unsafe considering that one can create a substring
-- starting and/or ending on the middle of a UTF8 sequence.
sub :: String -> Offset8 -> Offset8 -> String
sub (String ba) start end = String $ Vec.sub ba start end
-- | Internal call to split at a given index in offset of bytes.
--
-- This is unsafe considering that one can split in the middle of a
-- UTF8 sequence, so use with care.
splitIndex :: Offset8 -> String -> (String, String)
splitIndex idx (String ba) = (String v1, String v2)
where (v1,v2) = C.splitAt (offsetAsSize idx) ba
-- | Break a string into 2 strings at the location where the predicate return True
break :: (Char -> Bool) -> String -> (String, String)
break predicate s@(String ba) = runST $ Vec.unsafeIndexer ba go
where
!sz = size s
end = azero `offsetPlusE` sz
go :: (Offset Word8 -> Word8) -> ST st (String, String)
go getIdx = loop (Offset 0)
where
!nextI = nextWithIndexer getIdx
loop idx
| idx == end = return (s, mempty)
| otherwise = do
let (c, idx') = nextI idx
case predicate c of
True -> return $ splitIndex idx s
False -> loop idx'
{-# INLINE loop #-}
{-# INLINE [2] break #-}
#if MIN_VERSION_base(4,9,0)
{-# RULES "break (== 'c')" [3] forall c . break (eqChar c) = breakElem c #-}
#else
{-# RULES "break (== 'c')" [3] forall c . break (== c) = breakElem c #-}
#endif
-- | Break a string into 2 strings at the first occurence of the character
breakElem :: Char -> String -> (String, String)
breakElem !el s@(String ba)
| sz == 0 = (mempty, mempty)
| otherwise =
case asUTF8Char el of
UTF8_1 w -> let (# v1,v2 #) = Vec.splitElem w ba in (String v1, String v2)
_ -> runST $ Vec.unsafeIndexer ba go
where
sz = size s
end = azero `offsetPlusE` sz
go :: (Offset Word8 -> Word8) -> ST st (String, String)
go getIdx = loop (Offset 0)
where
!nextI = nextWithIndexer getIdx
loop idx
| idx == end = return (s, mempty)
| otherwise = do
let (c, idx') = nextI idx
case el == c of
True -> return $ splitIndex idx s
False -> loop idx'
-- | Apply a @predicate@ to the string to return the longest prefix that satisfy the predicate and
-- the remaining
span :: (Char -> Bool) -> String -> (String, String)
span predicate s = break (not . predicate) s
-- | Drop character from the beginning while the predicate is true
dropWhile :: (Char -> Bool) -> String -> String
dropWhile predicate = snd . break (not . predicate)
-- | Return whereas the string contains a specific character or not
elem :: Char -> String -> Bool
elem !el s@(String ba) =
case asUTF8Char el of
UTF8_1 w -> Vec.elem w ba
_ -> runST $ Vec.unsafeIndexer ba go
where
sz = size s
end = azero `offsetPlusE` sz
go :: (Offset Word8 -> Word8) -> ST st Bool
go getIdx = loop (Offset 0)
where
!nextI = nextWithIndexer getIdx
loop !idx
| idx == end = return False
| otherwise = do
let (c, idx') = nextI idx
case el == c of
True -> return True
False -> loop idx'
-- | Intersperse the character @sep@ between each character in the string
--
-- > intersperse ' ' "Hello Foundation"
-- "H e l l o F o u n d a t i o n"
intersperse :: Char -> String -> String
intersperse sep src
| srcLen <= 1 = src
| otherwise = runST $ unsafeCopyFrom src dstBytes (go sep)
where
!srcBytes = size src
!srcLen = length src
dstBytes = (srcBytes :: Size8)
+ ((srcLen - 1) `scale` charToBytes (fromEnum sep))
lastSrcI :: Offset Char
lastSrcI = 0 `offsetPlusE` (srcLen - 1)
go :: Char -> String -> Offset Char -> Offset8 -> MutableString s -> Offset8 -> ST s (Offset8, Offset8)
go sep' src' srcI srcIdx dst dstIdx
| srcI == lastSrcI = do
nextDstIdx <- write dst dstIdx c
return (nextSrcIdx, nextDstIdx)
| otherwise = do
nextDstIdx <- write dst dstIdx c
nextDstIdx' <- write dst nextDstIdx sep'
return (nextSrcIdx, nextDstIdx')
where
(# c, nextSrcIdx #) = next src' srcIdx
-- | Allocate a new @String@ with a fill function that has access to the characters of
-- the source @String@.
unsafeCopyFrom :: String -- ^ Source string
-> Size8 -- ^ Length of the destination string in bytes
-> (String -> Offset Char -> Offset8 -> MutableString s -> Offset8 -> ST s (Offset8, Offset8))
-- ^ Function called for each character in the source String
-> ST s String -- ^ Returns the filled new string
unsafeCopyFrom src dstBytes f = new dstBytes >>= fill (Offset 0) (Offset 0) (Offset 0) f >>= freeze
where
srcLen = length src
end = Offset 0 `offsetPlusE` srcLen
fill srcI srcIdx dstIdx f' dst'
| srcI == end = return dst'
| otherwise = do (nextSrcIdx, nextDstIdx) <- f' src srcI srcIdx dst' dstIdx
fill (srcI + Offset 1) nextSrcIdx nextDstIdx f' dst'
-- | Length of a String using CountOf
--
-- this size is available in o(n)
length :: String -> CountOf Char
length (String ba)
| C.null ba = CountOf 0
| otherwise = Vec.unsafeDewrap goVec goAddr ba
where
goVec ma start = loop start (CountOf 0)
where
!end = start `offsetPlusE` Vec.length ba
loop !idx !i
| idx >= end = i
| otherwise = loop (idx `offsetPlusE` d) (i + CountOf 1)
where d = skipNextHeaderValue (primBaIndex ma idx)
goAddr (Ptr ptr) start = return $ loop start (CountOf 0)
where
!end = start `offsetPlusE` Vec.length ba
loop !idx !i
| idx >= end = i
| otherwise = loop (idx `offsetPlusE` d) (i + CountOf 1)
where d = skipNextHeaderValue (primAddrIndex ptr idx)
-- | Replicate a character @c@ @n@ times to create a string of length @n@
replicate :: CountOf Char -> Char -> String
replicate (CountOf n) c = runST (new nbBytes >>= fill)
where
nbBytes = scale (integralCast n :: Word) sz
sz = charToBytes (fromEnum c)
fill :: PrimMonad prim => MutableString (PrimState prim) -> prim String
fill ms = loop (Offset 0)
where
loop idx
| idx .==# nbBytes = freeze ms
| otherwise = write ms idx c >>= loop
-- | Copy the String
--
-- The slice of memory is copied to a new slice, making the new string
-- independent from the original string..
copy :: String -> String
copy (String s) = String (Vec.copy s)
-- | Create a single element String
singleton :: Char -> String
singleton c = runST $ do
ms <- new nbBytes
_ <- write ms (Offset 0) c
freeze ms
where
!nbBytes = charToBytes (fromEnum c)
-- | Unsafely create a string of up to @sz@ bytes.
--
-- The callback @f@ needs to return the number of bytes filled in the underlaying
-- bytes buffer. No check is made on the callback return values, and if it's not
-- contained without the bounds, bad things will happen.
create :: PrimMonad prim => CountOf Word8 -> (MutableString (PrimState prim) -> prim (Offset Word8)) -> prim String
create sz f = do
ms <- new sz
filled <- f ms
if filled .==# sz
then freeze ms
else do
(String ba) <- freeze ms
pure $ String $ C.take (offsetAsSize filled) ba
-- | Monomorphically map the character in a string and return the transformed one
charMap :: (Char -> Char) -> String -> String
charMap f src
| srcSz == 0 = mempty
| otherwise =
let !(elems, nbBytes) = allocateAndFill [] (Offset 0) (CountOf 0)
in runST $ do
dest <- new nbBytes
copyLoop dest elems (Offset 0 `offsetPlusE` nbBytes)
freeze dest
where
!srcSz = size src
srcEnd = azero `offsetPlusE` srcSz
allocateAndFill :: [(String, Size8)]
-> Offset8
-> Size8
-> ([(String,Size8)], Size8)
allocateAndFill acc idx bytesWritten
| idx == srcEnd = (acc, bytesWritten)
| otherwise =
let (el@(_,addBytes), idx') = runST $ do
-- make sure we allocate at least 4 bytes for the destination for the last few bytes
-- otherwise allocating less would bring the danger of spinning endlessly
-- and never succeeding.
let !diffBytes = srcEnd - idx
!allocatedBytes = if diffBytes <= CountOf 4 then CountOf 4 else diffBytes
ms <- new allocatedBytes
(dstIdx, srcIdx) <- fill ms allocatedBytes idx
s <- freeze ms
return ((s, dstIdx), srcIdx)
in allocateAndFill (el : acc) idx' (bytesWritten + addBytes)
fill :: PrimMonad prim
=> MutableString (PrimState prim)
-> Size8
-> Offset8
-> prim (Size8, Offset8)
fill mba dsz srcIdxOrig =
loop (Offset 0) srcIdxOrig
where
endDst = (Offset 0) `offsetPlusE` dsz
loop dstIdx srcIdx
| srcIdx == srcEnd = return (offsetAsSize dstIdx, srcIdx)
| dstIdx == endDst = return (offsetAsSize dstIdx, srcIdx)
| otherwise =
let (# c, srcIdx' #) = next src srcIdx
c' = f c -- the mapped char
!nbBytes = charToBytes (fromEnum c')
in -- check if we have room in the destination buffer
if dstIdx `offsetPlusE` nbBytes <= sizeAsOffset dsz
then do dstIdx' <- write mba dstIdx c'
loop dstIdx' srcIdx'
else return (offsetAsSize dstIdx, srcIdx)
copyLoop _ [] (Offset 0) = return ()
copyLoop _ [] n = error ("charMap invalid: " <> show n)
copyLoop ms@(MutableString mba) ((String ba, sz):xs) end = do
let start = end `offsetMinusE` sz
Vec.unsafeCopyAtRO mba start ba (Offset 0) sz
copyLoop ms xs start
-- | Append a Char to the end of the String and return this new String
snoc :: String -> Char -> String
snoc s@(String ba) c
| len == CountOf 0 = singleton c
| otherwise = runST $ do
ms@(MutableString mba) <- new (len + nbBytes)
Vec.unsafeCopyAtRO mba (Offset 0) ba (Offset 0) len
_ <- write ms (azero `offsetPlusE` len) c
freeze ms
where
!len = size s
!nbBytes = charToBytes (fromEnum c)
-- | Prepend a Char to the beginning of the String and return this new String
cons :: Char -> String -> String
cons c s@(String ba)
| len == CountOf 0 = singleton c
| otherwise = runST $ do
ms@(MutableString mba) <- new (len + nbBytes)
idx <- write ms (Offset 0) c
Vec.unsafeCopyAtRO mba idx ba (Offset 0) len
freeze ms
where
!len = size s
!nbBytes = charToBytes (fromEnum c)
-- | Extract the String stripped of the last character and the last character if not empty
--
-- If empty, Nothing is returned
unsnoc :: String -> Maybe (String, Char)
unsnoc s@(String arr)
| sz == 0 = Nothing
| otherwise =
let (# c, idx #) = prev s (sizeAsOffset sz)
in Just (String $ Vec.take (offsetAsSize idx) arr, c)
where
sz = size s
-- | Extract the First character of a string, and the String stripped of the first character.
--
-- If empty, Nothing is returned
uncons :: String -> Maybe (Char, String)
uncons s@(String ba)
| null s = Nothing
| otherwise =
let (# c, idx #) = next s azero
in Just (c, String $ Vec.drop (offsetAsSize idx) ba)
-- | Look for a predicate in the String and return the matched character, if any.
find :: (Char -> Bool) -> String -> Maybe Char
find predicate s = loop (Offset 0)
where
!sz = size s
end = Offset 0 `offsetPlusE` sz
loop idx
| idx == end = Nothing
| otherwise =
let (# c, idx' #) = next s idx
in case predicate c of
True -> Just c
False -> loop idx'
-- | Sort the character in a String using a specific sort function
--
-- TODO: optimise not going through a list
sortBy :: (Char -> Char -> Ordering) -> String -> String
sortBy sortF s = fromList $ Data.List.sortBy sortF $ toList s -- FIXME for tests
-- | Filter characters of a string using the predicate
filter :: (Char -> Bool) -> String -> String
filter predicate (String arr) = runST $ do
(finalSize, dst) <- newNative sz $ \mba ->
case arr of
C.UVecBA start _ _ ba -> BackendBA.copyFilter predicate sz mba ba start
C.UVecAddr start _ fptr -> withFinalPtr fptr $ \(Ptr addr) -> BackendAddr.copyFilter predicate sz mba addr start
freezeShrink finalSize dst
where
!sz = C.length arr
-- | Reverse a string
reverse :: String -> String
reverse s@(String ba) = runST $ do
ms <- new len
loop ms (Offset 0) (Offset 0 `offsetPlusE` len)
where
!len = size s
-- write those bytes
loop :: PrimMonad prim => MutableString (PrimState prim) -> Offset8 -> Offset8 -> prim String
loop ms@(MutableString mba) si didx
| didx == Offset 0 = freeze ms
| otherwise = do
let !h = Vec.unsafeIndex ba si
!nb = CountOf (getNbBytes h + 1)
d = didx `offsetMinusE` nb
case nb of
CountOf 1 -> Vec.unsafeWrite mba d h
CountOf 2 -> do
Vec.unsafeWrite mba d h
Vec.unsafeWrite mba (d + 1) (Vec.unsafeIndex ba (si + 1))
CountOf 3 -> do
Vec.unsafeWrite mba d h
Vec.unsafeWrite mba (d + 1) (Vec.unsafeIndex ba (si + 1))
Vec.unsafeWrite mba (d + 2) (Vec.unsafeIndex ba (si + 2))
CountOf 4 -> do
Vec.unsafeWrite mba d h
Vec.unsafeWrite mba (d + 1) (Vec.unsafeIndex ba (si + 1))
Vec.unsafeWrite mba (d + 2) (Vec.unsafeIndex ba (si + 2))
Vec.unsafeWrite mba (d + 3) (Vec.unsafeIndex ba (si + 3))
_ -> return () -- impossible
loop ms (si `offsetPlusE` nb) d
-- Finds where are the insertion points when we search for a `needle`
-- within an `haystack`.
indices :: String -> String -> [Offset8]
indices (String ned) (String hy) = Vec.indices ned hy
-- | Replace all the occurrencies of `needle` with `replacement` in
-- the `haystack` string.
replace :: String -> String -> String -> String
replace (String needle) (String replacement) (String haystack) =
String $ Vec.replace needle replacement haystack
-- | Return the nth character in a String
--
-- Compared to an array, the string need to be scanned from the beginning
-- since the UTF8 encoding is variable.
index :: String -> Offset Char -> Maybe Char
index s n
| ofs >= end = Nothing
| otherwise =
let (# c, _ #) = next s ofs
in Just c
where
!nbBytes = size s
end = 0 `offsetPlusE` nbBytes
ofs = indexN (offsetAsSize n) s
-- | Return the index in unit of Char of the first occurence of the predicate returning True
--
-- If not found, Nothing is returned
findIndex :: (Char -> Bool) -> String -> Maybe (Offset Char)
findIndex predicate s = loop 0 0
where
!sz = size s
loop ofs idx
| idx .==# sz = Nothing
| otherwise =
let (# c, idx' #) = next s idx
in case predicate c of
True -> Just ofs
False -> loop (ofs+1) idx'
-- | Various String Encoding that can be use to convert to and from bytes
data Encoding
= ASCII7
| UTF8
| UTF16
| UTF32
| ISO_8859_1
deriving (Typeable, Data, Eq, Ord, Show, Enum, Bounded)
fromEncoderBytes :: ( Encoder.Encoding encoding
, PrimType (Encoder.Unit encoding)
)
=> encoding
-> UArray Word8
-> (String, Maybe ValidationFailure, UArray Word8)
fromEncoderBytes enc bytes =
case runST $ Encoder.convertFromTo enc EncoderUTF8 (Vec.recast bytes) of
-- TODO: Don't swallow up specific error (second element of pair)
-- TODO: Confused why all this recasting is necessary. I "typed hole"-ed my way to get this function to compile. Feels like there should be a cleaner method.
Left (off, _) ->
let (b1, b2) = Vec.splitAt (offsetAsSize off) (Vec.recast bytes)
in (String $ Vec.recast b1, Just BuildingFailure, Vec.recast b2)
Right converted -> (String converted, Nothing, mempty)
-- | Convert a ByteArray to a string assuming a specific encoding.
--
-- It returns a 3-tuple of:
--
-- * The string that has been succesfully converted without any error
-- * An optional validation error
-- * The remaining buffer that hasn't been processed (either as a result of an error, or because the encoded sequence is not fully available)
--
-- Considering a stream of data that is fetched chunk by chunk, it's valid to assume
-- that some sequence might fall in a chunk boundary. When converting chunks,
-- if the error is Nothing and the remaining buffer is not empty, then this buffer
-- need to be prepended to the next chunk
fromBytes :: Encoding -> UArray Word8 -> (String, Maybe ValidationFailure, UArray Word8)
fromBytes ASCII7 bytes = fromEncoderBytes Encoder.ASCII7 bytes
fromBytes ISO_8859_1 bytes = fromEncoderBytes Encoder.ISO_8859_1 bytes
fromBytes UTF16 bytes = fromEncoderBytes Encoder.UTF16 bytes
fromBytes UTF32 bytes = fromEncoderBytes Encoder.UTF32 bytes
fromBytes UTF8 bytes
| C.null bytes = (mempty, Nothing, mempty)
| otherwise =
case validate bytes (Offset 0) (C.length bytes) of
(_, Nothing) -> (fromBytesUnsafe bytes, Nothing, mempty)
(pos, Just vf) ->
let (b1, b2) = C.splitAt (offsetAsSize pos) bytes
in (fromBytesUnsafe b1, toErr vf, b2)
where
toErr MissingByte = Nothing
toErr InvalidHeader = Just InvalidHeader
toErr InvalidContinuation = Just InvalidContinuation
toErr BuildingFailure = Just BuildingFailure
-- | Convert a UTF8 array of bytes to a String.
--
-- If there's any error in the stream, it will automatically
-- insert replacement bytes to replace invalid sequences.
--
-- In the case of sequence that fall in the middle of 2 chunks,
-- the remaining buffer is supposed to be preprended to the
-- next chunk, and resume the parsing.
fromBytesLenient :: UArray Word8 -> (String, UArray Word8)
fromBytesLenient bytes
| C.null bytes = (mempty, mempty)
| otherwise =
case validate bytes (Offset 0) (C.length bytes) of
(_, Nothing) -> (fromBytesUnsafe bytes, mempty)
-- TODO: Should anything be done in the 'BuildingFailure' case?
(_, Just BuildingFailure) -> error "fromBytesLenient: FIXME!"
(pos, Just MissingByte) ->
let (b1,b2) = C.splitAt (offsetAsSize pos) bytes
in (fromBytesUnsafe b1, b2)
(pos, Just InvalidHeader) ->
let (b1,b2) = C.splitAt (offsetAsSize pos) bytes
(_,b3) = C.splitAt 1 b2
(s3, r) = fromBytesLenient b3
in (mconcat [fromBytesUnsafe b1,replacement, s3], r)
(pos, Just InvalidContinuation) ->
let (b1,b2) = C.splitAt (offsetAsSize pos) bytes
(_,b3) = C.splitAt 1 b2
(s3, r) = fromBytesLenient b3
in (mconcat [fromBytesUnsafe b1,replacement, s3], r)
where
-- This is the replacement character U+FFFD used for any invalid header or continuation
replacement :: String
!replacement = fromBytesUnsafe $ fromList [0xef,0xbf,0xbd]
-- | Decode a stream of binary chunks containing UTF8 encoding in a list of valid String
--
-- Chunk not necessarily contains a valid string, as
-- a UTF8 sequence could be split over 2 chunks.
fromChunkBytes :: [UArray Word8] -> [String]
fromChunkBytes l = loop l
where
loop [] = []
loop [bytes] =
case validate bytes (Offset 0) (C.length bytes) of
(_, Nothing) -> [fromBytesUnsafe bytes]
(_, Just err) -> doErr err
loop (bytes:cs@(c1:c2)) =
case validate bytes (Offset 0) (C.length bytes) of
(_, Nothing) -> fromBytesUnsafe bytes : loop cs
(pos, Just MissingByte) ->
let (b1,b2) = C.splitAt (offsetAsSize pos) bytes
in fromBytesUnsafe b1 : loop ((b2 `mappend` c1) : c2)
(_, Just err) -> doErr err
doErr err = error ("fromChunkBytes: " <> show err)
-- | Convert a Byte Array representing UTF8 data directly to a string without checking for UTF8 validity
--
-- If the input contains invalid sequences, it will trigger runtime async errors when processing data.
--
-- In doubt, use 'fromBytes'
fromBytesUnsafe :: UArray Word8 -> String
fromBytesUnsafe = String
toEncoderBytes :: ( Encoder.Encoding encoding
, PrimType (Encoder.Unit encoding)
, Exception (Encoder.Error encoding)
)
=> encoding
-> UArray Word8
-> UArray Word8
toEncoderBytes enc bytes = Vec.recast $
case runST $ Encoder.convertFromTo EncoderUTF8 enc bytes of
Left _ -> error "toEncoderBytes: FIXME!"
Right converted -> converted
-- | Convert a String to a bytearray in a specific encoding
--
-- if the encoding is UTF8, the underlying buffer is returned without extra allocation or any processing
--
-- In any other encoding, some allocation and processing are done to convert.
toBytes :: Encoding -> String -> UArray Word8
toBytes UTF8 (String bytes) = bytes
toBytes ASCII7 (String bytes) = toEncoderBytes Encoder.ASCII7 bytes
toBytes ISO_8859_1 (String bytes) = toEncoderBytes Encoder.ISO_8859_1 bytes
toBytes UTF16 (String bytes) = toEncoderBytes Encoder.UTF16 bytes
toBytes UTF32 (String bytes) = toEncoderBytes Encoder.UTF32 bytes
-- | Split lines in a string using newline as separation
lines :: String -> [String]
lines = fmap fromList . Prelude.lines . toList
-- | Split words in a string using spaces as separation
--
-- > words "Hello Foundation"
-- [ "Hello", "Foundation" ]
words :: String -> [String]
words = fmap fromList . Prelude.words . toList
-- | Append a character to a String builder
builderAppend :: PrimMonad state => Char -> Builder String MutableString Word8 state err ()
builderAppend c = Builder $ State $ \(i, st, e) ->
if offsetAsSize i + nbBytes >= chunkSize st
then do
cur <- unsafeFreezeShrink (curChunk st) (offsetAsSize i)
newChunk <- new (chunkSize st)
writeUTF8Char newChunk (Offset 0) utf8Char
return ((), (sizeAsOffset nbBytes, st { prevChunks = cur : prevChunks st
, prevChunksSize = offsetAsSize i + prevChunksSize st
, curChunk = newChunk
}, e))
else do
writeUTF8Char (curChunk st) i utf8Char
return ((), (i + sizeAsOffset nbBytes, st, e))
where
utf8Char = asUTF8Char c
nbBytes = numBytes utf8Char
-- | Create a new String builder using chunks of @sizeChunksI@
builderBuild :: PrimMonad m => Int -> Builder String MutableString Word8 m err () -> m (Either err String)
builderBuild sizeChunksI sb
| sizeChunksI <= 3 = builderBuild 64 sb
| otherwise = do
firstChunk <- new sizeChunks
((), (i, st, e)) <- runState (runBuilder sb) (Offset 0, BuildingState [] (CountOf 0) firstChunk sizeChunks, Nothing)
case e of
Just err -> return (Left err)
Nothing -> do
cur <- unsafeFreezeShrink (curChunk st) (offsetAsSize i)
-- Build final array
let totalSize = prevChunksSize st + offsetAsSize i
final <- Vec.new totalSize >>= fillFromEnd totalSize (cur : prevChunks st) >>= Vec.unsafeFreeze
return . Right . String $ final
where
sizeChunks = CountOf sizeChunksI
fillFromEnd _ [] mba = return mba
fillFromEnd !end (String x:xs) mba = do
let sz = Vec.length x
Vec.unsafeCopyAtRO mba (sizeAsOffset (end - sz)) x (Offset 0) sz
fillFromEnd (end - sz) xs mba
builderBuild_ :: PrimMonad m => Int -> Builder String MutableString Word8 m () () -> m String
builderBuild_ sizeChunksI sb = either (\() -> internalError "impossible output") id <$> builderBuild sizeChunksI sb
stringDewrap :: (ByteArray# -> Offset Word8 -> a)
-> (Ptr Word8 -> Offset Word8 -> ST s a)
-> String
-> a
stringDewrap withBa withPtr (String ba) = C.unsafeDewrap withBa withPtr ba
{-# INLINE stringDewrap #-}
-- | Read an Integer from a String
--
-- Consume an optional minus sign and many digits until end of string.
readIntegral :: (HasNegation i, IntegralUpsize Word8 i, Additive i, Multiplicative i, IsIntegral i) => String -> Maybe i
readIntegral str
| sz == 0 = Nothing
| otherwise = stringDewrap withBa withPtr str
where
!sz = size str
withBa ba ofs =
let negativeSign = PrimBA.expectAscii ba ofs 0x2d
startOfs = if negativeSign then succ ofs else ofs
in case decimalDigitsBA 0 ba endOfs startOfs of
(# acc, True, endOfs' #) | endOfs' > startOfs -> Just $! if negativeSign then negate acc else acc
_ -> Nothing
where !endOfs = ofs `offsetPlusE` sz
withPtr (Ptr ptr) ofs = return $
let negativeSign = PrimAddr.expectAscii ptr ofs 0x2d
startOfs = if negativeSign then succ ofs else ofs
in case decimalDigitsPtr 0 ptr endOfs startOfs of
(# acc, True, endOfs' #) | endOfs' > startOfs -> Just $! if negativeSign then negate acc else acc
_ -> Nothing
where !endOfs = ofs `offsetPlusE` sz
{-# SPECIALISE readIntegral :: String -> Maybe Integer #-}
{-# SPECIALISE readIntegral :: String -> Maybe Int #-}
readInteger :: String -> Maybe Integer
readInteger = readIntegral
-- | Read a Natural from a String
--
-- Consume many digits until end of string.
readNatural :: String -> Maybe Natural
readNatural str
| sz == 0 = Nothing
| otherwise =
case decimalDigits 0 str 0 of
(# acc, True, endOfs #) | endOfs > 0 -> Just acc
_ -> Nothing
where
!sz = size str
-- | Try to read a Double
readDouble :: String -> Maybe Double
readDouble s =
readFloatingExact s $ \isNegative integral floatingDigits mExponant ->
Just $ applySign isNegative $ case (floatingDigits, mExponant) of
(0, Nothing) -> naturalToDouble integral
(0, Just exponent) -> withExponant exponent $ naturalToDouble integral
(floating, Nothing) -> applyFloating floating $ naturalToDouble integral
(floating, Just exponent) -> withExponant exponent $ applyFloating floating $ naturalToDouble integral
where
applySign True = negate
applySign False = id
withExponant e v = v * doubleExponant 10 e
applyFloating digits n = n / (10 Prelude.^ digits)
-- | Try to read a floating number as a Rational
--
-- Note that for safety reason, only exponent between -10000 and 10000 is allowed
-- as otherwise DoS/OOM is very likely. if you don't want this behavior,
-- switching to a scientific type (not provided yet) that represent the
-- exponent separately is the advised solution.
readRational :: String -> Maybe Prelude.Rational
readRational s =
readFloatingExact s $ \isNegative integral floatingDigits mExponant ->
case mExponant of
Just exponent
| exponent < -10000 || exponent > 10000 -> Nothing
| otherwise -> Just $ modF isNegative integral % (10 Prelude.^ (integralCast floatingDigits - exponent))
Nothing -> Just $ modF isNegative integral % (10 Prelude.^ floatingDigits)
where
modF True = negate . integralUpsize
modF False = integralUpsize
type ReadFloatingCallback a = Bool -- sign
-> Natural -- integral part
-> Word -- number of digits in floating section
-> Maybe Int -- optional integer representing exponent in base 10
-> Maybe a
-- | Read an Floating like number of the form:
--
-- [ '-' ] <numbers> [ '.' <numbers> ] [ ( 'e' | 'E' ) [ '-' ] <number> ]
--
-- Call a function with:
--
-- * A boolean representing if the number is negative
-- * The digits part represented as a single natural number (123.456 is represented as 123456)
-- * The number of digits in the fractional part (e.g. 123.456 => 3)
-- * The exponent if any
--
-- The code is structured as a simple state machine that:
--
-- * Optionally Consume a '-' sign
-- * Consume number for the integral part
-- * Optionally
-- * Consume '.'
-- * Consume remaining digits if not already end of string
-- * Optionally Consume a 'e' or 'E' follow by an optional '-' and a number
--
readFloatingExact :: String -> ReadFloatingCallback a -> Maybe a
readFloatingExact str f
| sz == 0 = Nothing
| otherwise = stringDewrap withBa withPtr str
where
!sz = size str
withBa ba stringStart =
let !isNegative = PrimBA.expectAscii ba stringStart 0x2d
in consumeIntegral isNegative (if isNegative then stringStart+1 else stringStart)
where
eofs = stringStart `offsetPlusE` sz
consumeIntegral !isNegative startOfs =
case decimalDigitsBA 0 ba eofs startOfs of
(# acc, True , endOfs #) | endOfs > startOfs -> f isNegative acc 0 Nothing -- end of stream and no '.'
(# acc, False, endOfs #) | endOfs > startOfs ->
if PrimBA.expectAscii ba endOfs 0x2e
then consumeFloat isNegative acc (endOfs + 1)
else consumeExponant isNegative acc 0 endOfs
_ -> Nothing
consumeFloat isNegative integral startOfs =
case decimalDigitsBA integral ba eofs startOfs of
(# acc, True, endOfs #) | endOfs > startOfs -> let (CountOf !diff) = endOfs - startOfs
in f isNegative acc (integralCast diff) Nothing
(# acc, False, endOfs #) | endOfs > startOfs -> let (CountOf !diff) = endOfs - startOfs
in consumeExponant isNegative acc (integralCast diff) endOfs
_ -> Nothing
consumeExponant !isNegative !integral !floatingDigits !startOfs
| startOfs == eofs = f isNegative integral floatingDigits Nothing
| otherwise =
-- consume 'E' or 'e'
case PrimBA.nextAscii ba startOfs of
(# 0x45, True #) -> consumeExponantSign (startOfs+1)
(# 0x65, True #) -> consumeExponantSign (startOfs+1)
(# _ , _ #) -> Nothing
where
consumeExponantSign ofs
| ofs == eofs = Nothing
| otherwise = let exponentNegative = PrimBA.expectAscii ba ofs 0x2d
in consumeExponantNumber exponentNegative (if exponentNegative then ofs + 1 else ofs)
consumeExponantNumber exponentNegative ofs =
case decimalDigitsBA 0 ba eofs ofs of
(# acc, True, endOfs #) | endOfs > ofs -> f isNegative integral floatingDigits (Just $! if exponentNegative then negate acc else acc)
_ -> Nothing
withPtr (Ptr ptr) stringStart = return $
let !isNegative = PrimAddr.expectAscii ptr stringStart 0x2d
in consumeIntegral isNegative (if isNegative then stringStart+1 else stringStart)
where
eofs = stringStart `offsetPlusE` sz
consumeIntegral !isNegative startOfs =
case decimalDigitsPtr 0 ptr eofs startOfs of
(# acc, True , endOfs #) | endOfs > startOfs -> f isNegative acc 0 Nothing -- end of stream and no '.'
(# acc, False, endOfs #) | endOfs > startOfs ->
if PrimAddr.expectAscii ptr endOfs 0x2e
then consumeFloat isNegative acc (endOfs + 1)
else consumeExponant isNegative acc 0 endOfs
_ -> Nothing
consumeFloat isNegative integral startOfs =
case decimalDigitsPtr integral ptr eofs startOfs of
(# acc, True, endOfs #) | endOfs > startOfs -> let (CountOf !diff) = endOfs - startOfs
in f isNegative acc (integralCast diff) Nothing
(# acc, False, endOfs #) | endOfs > startOfs -> let (CountOf !diff) = endOfs - startOfs
in consumeExponant isNegative acc (integralCast diff) endOfs
_ -> Nothing
consumeExponant !isNegative !integral !floatingDigits !startOfs
| startOfs == eofs = f isNegative integral floatingDigits Nothing
| otherwise =
-- consume 'E' or 'e'
case PrimAddr.nextAscii ptr startOfs of
(# 0x45, True #) -> consumeExponantSign (startOfs+1)
(# 0x65, True #) -> consumeExponantSign (startOfs+1)
(# _ , _ #) -> Nothing
where
consumeExponantSign ofs
| ofs == eofs = Nothing
| otherwise = let exponentNegative = PrimAddr.expectAscii ptr ofs 0x2d
in consumeExponantNumber exponentNegative (if exponentNegative then ofs + 1 else ofs)
consumeExponantNumber exponentNegative ofs =
case decimalDigitsPtr 0 ptr eofs ofs of
(# acc, True, endOfs #) | endOfs > ofs -> f isNegative integral floatingDigits (Just $! if exponentNegative then negate acc else acc)
_ -> Nothing
-- | Take decimal digits and accumulate it in `acc`
--
-- The loop starts at the offset specified and finish either when:
--
-- * It reach the end of the string
-- * It reach a non-ASCII character
-- * It reach an ASCII character that is not a digit (0 to 9)
--
-- Otherwise each iterations:
--
-- * Transform the ASCII digits into a number
-- * scale the accumulator by 10
-- * Add the number (between 0 and 9) to the accumulator
--
-- It then returns:
--
-- * The new accumulated value
-- * Whether it stop by end of string or not
-- * The end offset when the loop stopped
--
-- If end offset == start offset then no digits have been consumed by
-- this function
decimalDigits :: (IntegralUpsize Word8 acc, Additive acc)
=> acc
-> String
-> Offset Word8
-> (# acc, Bool, Offset Word8 #)
decimalDigits startAcc str startOfs = loop startAcc startOfs
where
!sz = size str
loop acc ofs
| ofs .==# sz = (# acc, True, ofs #)
| otherwise =
case nextAscii str ofs of
(# d, True #) | isDigit d -> loop (scale (10::Word) acc + fromDigit d) (ofs+1)
(# _, _ #) -> (# acc, False, ofs #)
ascii0 = 0x30 -- use pattern synonym when we support >= 8.0
ascii9 = 0x39
isDigit c = c >= ascii0 && c <= ascii9
fromDigit c = integralUpsize (c - ascii0)
-- | same as decimalDigitsBA for a bytearray#
decimalDigitsBA :: (IntegralUpsize Word8 acc, Additive acc, Multiplicative acc, Integral acc)
=> acc
-> ByteArray#
-> Offset Word8 -- end offset
-> Offset Word8 -- start offset
-> (# acc, Bool, Offset Word8 #)
decimalDigitsBA startAcc ba !endOfs !startOfs = loop startAcc startOfs
where
loop !acc !ofs
| ofs == endOfs = (# acc, True, ofs #)
| otherwise =
case PrimBA.nextAsciiDigit ba ofs of
(# d, True #) -> loop (10 * acc + integralUpsize d) (succ ofs)
(# _, _ #) -> (# acc, False, ofs #)
{-# SPECIALIZE decimalDigitsBA :: Integer -> ByteArray# -> Offset Word8 -> Offset Word8 -> (# Integer, Bool, Offset Word8 #) #-}
{-# SPECIALIZE decimalDigitsBA :: Natural -> ByteArray# -> Offset Word8 -> Offset Word8 -> (# Natural, Bool, Offset Word8 #) #-}
{-# SPECIALIZE decimalDigitsBA :: Int -> ByteArray# -> Offset Word8 -> Offset Word8 -> (# Int, Bool, Offset Word8 #) #-}
{-# SPECIALIZE decimalDigitsBA :: Word -> ByteArray# -> Offset Word8 -> Offset Word8 -> (# Word, Bool, Offset Word8 #) #-}
-- | same as decimalDigitsBA specialized for ptr #
decimalDigitsPtr :: (IntegralUpsize Word8 acc, Additive acc, Multiplicative acc, Integral acc)
=> acc
-> Addr#
-> Offset Word8 -- end offset
-> Offset Word8 -- start offset
-> (# acc, Bool, Offset Word8 #)
decimalDigitsPtr startAcc ptr !endOfs !startOfs = loop startAcc startOfs
where
loop !acc !ofs
| ofs == endOfs = (# acc, True, ofs #)
| otherwise =
case PrimAddr.nextAsciiDigit ptr ofs of
(# d, True #) -> loop (10 * acc + integralUpsize d) (succ ofs)
(# _, _ #) -> (# acc, False, ofs #)
{-# SPECIALIZE decimalDigitsPtr :: Integer -> Addr# -> Offset Word8 -> Offset Word8 -> (# Integer, Bool, Offset Word8 #) #-}
{-# SPECIALIZE decimalDigitsPtr :: Natural -> Addr# -> Offset Word8 -> Offset Word8 -> (# Natural, Bool, Offset Word8 #) #-}
{-# SPECIALIZE decimalDigitsPtr :: Int -> Addr# -> Offset Word8 -> Offset Word8 -> (# Int, Bool, Offset Word8 #) #-}
{-# SPECIALIZE decimalDigitsPtr :: Word -> Addr# -> Offset Word8 -> Offset Word8 -> (# Word, Bool, Offset Word8 #) #-}
-- | Convert a 'String' to the upper-case equivalent.
-- Does not properly support multicharacter Unicode conversions.
upper :: String -> String
upper = charMap toUpper
-- | Convert a 'String' to the upper-case equivalent.
-- Does not properly support multicharacter Unicode conversions.
lower :: String -> String
lower = charMap toLower
-- | Check whether the first string is a prefix of the second string.
isPrefixOf :: String -> String -> Bool
isPrefixOf (String needle) (String haystack)
| needleLen > hayLen = False
| otherwise = needle == C.take needleLen haystack
where
needleLen = C.length needle
hayLen = C.length haystack
-- | Check whether the first string is a suffix of the second string.
isSuffixOf :: String -> String -> Bool
isSuffixOf (String needle) (String haystack)
| needleLen > hayLen = False
| otherwise = needle == C.revTake needleLen haystack
where
needleLen = C.length needle
hayLen = C.length haystack
-- | Check whether the first string is contains within the second string.
--
-- TODO: implemented the naive way and thus terribly inefficient, reimplement properly
isInfixOf :: String -> String -> Bool
isInfixOf (String needle) (String haystack)
| needleLen > hayLen = False
| otherwise = loop 0
where
endOfs = hayLen - needleLen
needleLen = C.length needle
hayLen = C.length haystack
loop i
| i == endOfs = needle == haystackSub
| needle == haystackSub = True
| otherwise = loop (i+1)
where haystackSub = C.take needleLen $ C.drop i haystack
-- | Transform string @src@ to base64 binary representation.
toBase64 :: String -> String
toBase64 (String src) = fromBytesUnsafe . Vec.toBase64Internal set src $ True
where
!set = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"#
-- | Transform string @src@ to URL-safe base64 binary representation.
-- The result will be either padded or unpadded, depending on the boolean
-- @padded@ argument.
toBase64URL :: Bool -> String -> String
toBase64URL padded (String src) = fromBytesUnsafe . Vec.toBase64Internal set src $ padded
where
!set = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"#
-- | Transform string @src@ to OpenBSD base64 binary representation.
toBase64OpenBSD :: String -> String
toBase64OpenBSD (String src) = fromBytesUnsafe . Vec.toBase64Internal set src $ False
where
!set = "./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"#