rio-0.1.22.0: A standard library for Haskell
Safe HaskellSafe-Inferred
LanguageHaskell2010

RIO.ByteString

Description

Strict ByteString. Import as:

import qualified RIO.ByteString as B

This module does not export any partial functions. For those, see RIO.ByteString.Partial

Synopsis

Documentation

data ByteString Source #

A space-efficient representation of a Word8 vector, supporting many efficient operations.

A ByteString contains 8-bit bytes, or by using the operations from Data.ByteString.Char8 it can be interpreted as containing 8-bit characters.

Instances

Instances details
Data ByteString 
Instance details

Defined in Data.ByteString.Internal

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> ByteString -> c ByteString Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c ByteString Source #

toConstr :: ByteString -> Constr Source #

dataTypeOf :: ByteString -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ByteString) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ByteString) Source #

gmapT :: (forall b. Data b => b -> b) -> ByteString -> ByteString Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> ByteString -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> ByteString -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> ByteString -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> ByteString -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString Source #

IsString ByteString

Beware: fromString truncates multi-byte characters to octets. e.g. "枯朶に烏のとまりけり秋の暮" becomes �6k�nh~�Q��n�

Instance details

Defined in Data.ByteString.Internal

Monoid ByteString 
Instance details

Defined in Data.ByteString.Internal

Semigroup ByteString 
Instance details

Defined in Data.ByteString.Internal

IsList ByteString

Since: bytestring-0.10.12.0

Instance details

Defined in Data.ByteString.Internal

Associated Types

type Item ByteString Source #

Read ByteString 
Instance details

Defined in Data.ByteString.Internal

Show ByteString 
Instance details

Defined in Data.ByteString.Internal

NFData ByteString 
Instance details

Defined in Data.ByteString.Internal

Methods

rnf :: ByteString -> () Source #

Eq ByteString 
Instance details

Defined in Data.ByteString.Internal

Ord ByteString 
Instance details

Defined in Data.ByteString.Internal

Hashable ByteString 
Instance details

Defined in Data.Hashable.Class

type Item ByteString 
Instance details

Defined in Data.ByteString.Internal

zipWith :: (Word8 -> Word8 -> a) -> ByteString -> ByteString -> [a] Source #

zipWith generalises zip by zipping with the function given as the first argument, instead of a tupling function. For example, zipWith (+) is applied to two ByteStrings to produce the list of corresponding sums.

zip :: ByteString -> ByteString -> [(Word8, Word8)] Source #

O(n) zip takes two ByteStrings and returns a list of corresponding pairs of bytes. If one input ByteString is short, excess elements of the longer ByteString are discarded. This is equivalent to a pair of unpack operations.

unzip :: [(Word8, Word8)] -> (ByteString, ByteString) Source #

O(n) unzip transforms a list of pairs of bytes into a pair of ByteStrings. Note that this performs two pack operations.

unsnoc :: ByteString -> Maybe (ByteString, Word8) Source #

O(1) Extract the init and last of a ByteString, returning Nothing if it is empty.

unpack :: ByteString -> [Word8] Source #

O(n) Converts a ByteString to a [Word8].

unfoldrN :: Int -> (a -> Maybe (Word8, a)) -> a -> (ByteString, Maybe a) Source #

O(n) Like unfoldr, unfoldrN builds a ByteString from a seed value. However, the length of the result is limited by the first argument to unfoldrN. This function is more efficient than unfoldr when the maximum length of the result is known.

The following equation relates unfoldrN and unfoldr:

fst (unfoldrN n f s) == take n (unfoldr f s)

unfoldr :: (a -> Maybe (Word8, a)) -> a -> ByteString Source #

O(n), where n is the length of the result. The unfoldr function is analogous to the List 'unfoldr'. unfoldr builds a ByteString from a seed value. The function takes the element and returns Nothing if it is done producing the ByteString or returns Just (a,b), in which case, a is the next byte in the string, and b is the seed value for further production.

Examples:

   unfoldr (\x -> if x <= 5 then Just (x, x + 1) else Nothing) 0
== pack [0, 1, 2, 3, 4, 5]

uncons :: ByteString -> Maybe (Word8, ByteString) Source #

O(1) Extract the head and tail of a ByteString, returning Nothing if it is empty.

transpose :: [ByteString] -> [ByteString] Source #

The transpose function transposes the rows and columns of its ByteString argument.

takeWhileEnd :: (Word8 -> Bool) -> ByteString -> ByteString Source #

takeWhileEnd, applied to a predicate p and a ByteString xs, returns the longest suffix (possibly empty) of xs of elements that satisfy p.

Since: bytestring-0.10.12.0

takeWhile :: (Word8 -> Bool) -> ByteString -> ByteString Source #

takeWhile, applied to a predicate p and a ByteString xs, returns the longest prefix (possibly empty) of xs of elements that satisfy p.

take :: Int -> ByteString -> ByteString Source #

O(1) take n, applied to a ByteString xs, returns the prefix of xs of length n, or xs itself if n > length xs.

tails :: ByteString -> [ByteString] Source #

O(n) Return all final segments of the given ByteString, longest first.

stripSuffix :: ByteString -> ByteString -> Maybe ByteString Source #

O(n) The stripSuffix function takes two ByteStrings and returns Just the remainder of the second iff the first is its suffix, and otherwise Nothing.

stripPrefix :: ByteString -> ByteString -> Maybe ByteString Source #

O(n) The stripPrefix function takes two ByteStrings and returns Just the remainder of the second iff the first is its prefix, and otherwise Nothing.

Since: bytestring-0.10.8.0

splitWith :: (Word8 -> Bool) -> ByteString -> [ByteString] Source #

O(n) Splits a ByteString 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.

splitWith (==97) "aabbaca" == ["","","bb","c",""] -- fromEnum 'a' == 97
splitWith (==97) []        == []

splitAt :: Int -> ByteString -> (ByteString, ByteString) Source #

O(1) splitAt n xs is equivalent to (take n xs, drop n xs).

split :: Word8 -> ByteString -> [ByteString] Source #

O(n) Break a ByteString into pieces separated by the byte argument, consuming the delimiter. I.e.

split 10  "a\nb\nd\ne" == ["a","b","d","e"]   -- fromEnum '\n' == 10
split 97  "aXaXaXa"    == ["","X","X","X",""] -- fromEnum 'a' == 97
split 120 "x"          == ["",""]             -- fromEnum 'x' == 120

and

intercalate [c] . split c == id
split == splitWith . (==)

As for all splitting functions in this library, this function does not copy the substrings, it just constructs new ByteStrings that are slices of the original.

spanEnd :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString) Source #

spanEnd behaves like span but from the end of the ByteString. We have

spanEnd (not.isSpace) "x y z" == ("x y ","z")

and

spanEnd (not . isSpace) ps
   ==
let (x,y) = span (not.isSpace) (reverse ps) in (reverse y, reverse x)

span :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString) Source #

span p xs breaks the ByteString into two segments. It is equivalent to (takeWhile p xs, dropWhile p xs)

sort :: ByteString -> ByteString Source #

O(n) Sort a ByteString efficiently, using counting sort.

snoc :: ByteString -> Word8 -> ByteString infixl 5 Source #

O(n) Append a byte to the end of a ByteString

singleton :: Word8 -> ByteString Source #

O(1) Convert a Word8 into a ByteString

scanr1 :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString Source #

scanr1 is a variant of scanr that has no starting value argument.

scanr :: (Word8 -> Word8 -> Word8) -> Word8 -> ByteString -> ByteString Source #

scanr is the right-to-left dual of scanl.

scanl1 :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString Source #

scanl1 is a variant of scanl that has no starting value argument. This function will fuse.

scanl1 f [x1, x2, ...] == [x1, x1 `f` x2, ...]

scanl :: (Word8 -> Word8 -> Word8) -> Word8 -> ByteString -> ByteString Source #

scanl is similar to foldl, but returns a list of successive reduced values from the left. This function will fuse.

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.

reverse :: ByteString -> ByteString Source #

O(n) reverse xs efficiently returns the elements of xs in reverse order.

replicate :: Int -> Word8 -> ByteString Source #

O(n) replicate n x is a ByteString of length n with x the value of every element. The following holds:

replicate w c = unfoldr w (\u -> Just (u,u)) c

This implemenation uses memset(3)

partition :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString) Source #

O(n) The partition function takes a predicate a ByteString and returns the pair of ByteStrings with elements which do and do not satisfy the predicate, respectively; i.e.,

partition p bs == (filter p xs, filter (not . p) xs)

pack :: [Word8] -> ByteString Source #

O(n) Convert a [Word8] into a ByteString.

For applications with large numbers of string literals, pack can be a bottleneck. In such cases, consider using unsafePackAddress (GHC only).

null :: ByteString -> Bool Source #

O(1) Test whether a ByteString is empty.

notElem :: Word8 -> ByteString -> Bool Source #

O(n) notElem is the inverse of elem

mapAccumR :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString) Source #

The mapAccumR function behaves like a combination of map and foldr; it applies a function to each element of a ByteString, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new ByteString.

mapAccumL :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString) Source #

The mapAccumL function behaves like a combination of map and foldl; it applies a function to each element of a ByteString, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new list.

map :: (Word8 -> Word8) -> ByteString -> ByteString Source #

O(n) map f xs is the ByteString obtained by applying f to each element of xs.

length :: ByteString -> Int Source #

O(1) length returns the length of a ByteString as an Int.

isSuffixOf :: ByteString -> ByteString -> Bool Source #

O(n) The isSuffixOf function takes two ByteStrings and returns True iff the first is a suffix of the second.

The following holds:

isSuffixOf x y == reverse x `isPrefixOf` reverse y

However, the real implemenation uses memcmp to compare the end of the string only, with no reverse required..

isPrefixOf :: ByteString -> ByteString -> Bool Source #

O(n) The isPrefixOf function takes two ByteStrings and returns True if the first is a prefix of the second.

isInfixOf :: ByteString -> ByteString -> Bool Source #

Check whether one string is a substring of another. isInfixOf p s is equivalent to not (null (findSubstrings p s)).

intersperse :: Word8 -> ByteString -> ByteString Source #

O(n) The intersperse function takes a Word8 and a ByteString and `intersperses' that byte between the elements of the ByteString. It is analogous to the intersperse function on Lists.

intercalate :: ByteString -> [ByteString] -> ByteString Source #

O(n) The intercalate function takes a ByteString and a list of ByteStrings and concatenates the list after interspersing the first argument between each element of the list.

inits :: ByteString -> [ByteString] Source #

O(n) Return all initial segments of the given ByteString, shortest first.

index :: ByteString -> Int -> Word8 Source #

O(1) ByteString index (subscript) operator, starting from 0.

groupBy :: (Word8 -> Word8 -> Bool) -> ByteString -> [ByteString] Source #

The groupBy function is the non-overloaded version of group.

group :: ByteString -> [ByteString] Source #

The group function takes a ByteString and returns a list of ByteStrings such that the concatenation of the result is equal to the argument. Moreover, each sublist in the result contains only equal elements. For example,

group "Mississippi" = ["M","i","ss","i","ss","i","pp","i"]

It is a special case of groupBy, which allows the programmer to supply their own equality test. It is about 40% faster than groupBy (==)

foldr' :: (Word8 -> a -> a) -> a -> ByteString -> a Source #

foldr' is like foldr, but strict in the accumulator.

foldr :: (Word8 -> a -> a) -> a -> ByteString -> a Source #

foldr, applied to a binary operator, a starting value (typically the right-identity of the operator), and a ByteString, reduces the ByteString using the binary operator, from right to left.

foldl' :: (a -> Word8 -> a) -> a -> ByteString -> a Source #

foldl' is like foldl, but strict in the accumulator.

foldl :: (a -> Word8 -> a) -> a -> ByteString -> a Source #

foldl, applied to a binary operator, a starting value (typically the left-identity of the operator), and a ByteString, reduces the ByteString using the binary operator, from left to right.

findIndices :: (Word8 -> Bool) -> ByteString -> [Int] Source #

O(n) The findIndices function extends findIndex, by returning the indices of all elements satisfying the predicate, in ascending order.

findIndexEnd :: (Word8 -> Bool) -> ByteString -> Maybe Int Source #

O(n) The findIndexEnd function takes a predicate and a ByteString and returns the index of the last element in the ByteString satisfying the predicate.

Since: bytestring-0.10.12.0

findIndex :: (Word8 -> Bool) -> ByteString -> Maybe Int Source #

O(n) The findIndex function takes a predicate and a ByteString and returns the index of the first element in the ByteString satisfying the predicate.

find :: (Word8 -> Bool) -> ByteString -> Maybe Word8 Source #

O(n) The find function takes a predicate and a ByteString, and returns the first element in matching the predicate, or Nothing if there is no such element.

find f p = case findIndex f p of Just n -> Just (p ! n) ; _ -> Nothing

filter :: (Word8 -> Bool) -> ByteString -> ByteString Source #

O(n) filter, applied to a predicate and a ByteString, returns a ByteString containing those characters that satisfy the predicate.

elemIndices :: Word8 -> ByteString -> [Int] Source #

O(n) The elemIndices function extends elemIndex, by returning the indices of all elements equal to the query element, in ascending order. This implementation uses memchr(3).

elemIndexEnd :: Word8 -> ByteString -> Maybe Int Source #

O(n) The elemIndexEnd function returns the last index of the element in the given ByteString which is equal to the query element, or Nothing if there is no such element. The following holds:

elemIndexEnd c xs ==
(-) (length xs - 1) `fmap` elemIndex c (reverse xs)

elemIndex :: Word8 -> ByteString -> Maybe Int Source #

O(n) The elemIndex function returns the index of the first element in the given ByteString which is equal to the query element, or Nothing if there is no such element. This implementation uses memchr(3).

elem :: Word8 -> ByteString -> Bool Source #

O(n) elem is the ByteString membership predicate.

dropWhileEnd :: (Word8 -> Bool) -> ByteString -> ByteString Source #

dropWhileEnd p xs returns the prefix remaining after takeWhileEnd p xs.

Since: bytestring-0.10.12.0

dropWhile :: (Word8 -> Bool) -> ByteString -> ByteString Source #

dropWhile p xs returns the suffix remaining after takeWhile p xs.

drop :: Int -> ByteString -> ByteString Source #

O(1) drop n xs returns the suffix of xs after the first n elements, or [] if n > length xs.

count :: Word8 -> ByteString -> Int Source #

count returns the number of times its argument appears in the ByteString

count = length . elemIndices

But more efficiently than using length on the intermediate list.

copy :: ByteString -> ByteString Source #

O(n) Make a copy of the ByteString with its own storage. This is mainly useful to allow the rest of the data pointed to by the ByteString to be garbage collected, for example if a large string has been read in, and only a small part of it is needed in the rest of the program.

cons :: Word8 -> ByteString -> ByteString infixr 5 Source #

O(n) cons is analogous to (:) for lists, but of different complexity, as it requires making a copy.

concatMap :: (Word8 -> ByteString) -> ByteString -> ByteString Source #

Map a function over a ByteString and concatenate the results

concat :: [ByteString] -> ByteString Source #

O(n) Concatenate a list of ByteStrings.

breakSubstring Source #

Arguments

:: ByteString

String to search for

-> ByteString

String to search in

-> (ByteString, ByteString)

Head and tail of string broken at substring

Break a string on a substring, returning a pair of the part of the string prior to the match, and the rest of the string.

The following relationships hold:

break (== c) l == breakSubstring (singleton c) l

and:

findSubstring s l ==
   if null s then Just 0
             else case breakSubstring s l of
                      (x,y) | null y    -> Nothing
                            | otherwise -> Just (length x)

For example, to tokenise a string, dropping delimiters:

tokenise x y = h : if null t then [] else tokenise x (drop (length x) t)
    where (h,t) = breakSubstring x y

To skip to the first occurence of a string:

snd (breakSubstring x y)

To take the parts of a string before a delimiter:

fst (breakSubstring x y)

Note that calling `breakSubstring x` does some preprocessing work, so you should avoid unnecessarily duplicating breakSubstring calls with the same pattern.

breakEnd :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString) Source #

breakEnd behaves like break but from the end of the ByteString

breakEnd p == spanEnd (not.p)

break :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString) Source #

break p is equivalent to span (not . p).

Under GHC, a rewrite rule will transform break (==) into a call to the specialised breakByte:

break ((==) x) = breakByte x
break (==x) = breakByte x

append :: ByteString -> ByteString -> ByteString Source #

O(n) Append two ByteStrings

any :: (Word8 -> Bool) -> ByteString -> Bool Source #

O(n) Applied to a predicate and a ByteString, any determines if any element of the ByteString satisfies the predicate.

all :: (Word8 -> Bool) -> ByteString -> Bool Source #

O(n) Applied to a predicate and a ByteString, all determines if all elements of the ByteString satisfy the predicate.

useAsCString :: MonadUnliftIO m => ByteString -> (CString -> m a) -> m a Source #

Unlifted useAsCString

putStr :: MonadIO m => ByteString -> m () Source #

Lifted putStr

hGet :: MonadIO m => Handle -> Int -> m ByteString Source #

Lifted hGet

hPut :: MonadIO m => Handle -> ByteString -> m () Source #

Lifted hPut

hPutStr :: MonadIO m => Handle -> ByteString -> m () Source #

Lifted hPutStr