ByteString.Lazy

Documentation

data ByteString

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

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

Instances

Eq ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

(==) :: ByteString -> ByteString -> Bool

(/=) :: ByteString -> ByteString -> Bool

Data ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

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

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

toConstr :: ByteString -> Constr

dataTypeOf :: ByteString -> DataType

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

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

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

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

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

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

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

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

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

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

Ord ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

compare :: ByteString -> ByteString -> Ordering

(<) :: ByteString -> ByteString -> Bool

(<=) :: ByteString -> ByteString -> Bool

(>) :: ByteString -> ByteString -> Bool

(>=) :: ByteString -> ByteString -> Bool

max :: ByteString -> ByteString -> ByteString

min :: ByteString -> ByteString -> ByteString

Read ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

readsPrec :: Int -> ReadS ByteString

readList :: ReadS [ByteString]

readPrec :: ReadPrec ByteString

readListPrec :: ReadPrec [ByteString]

Show ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

showsPrec :: Int -> ByteString -> ShowS

show :: ByteString -> String

showList :: [ByteString] -> ShowS

IsString ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

fromString :: String -> ByteString

Semigroup ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

(<>) :: ByteString -> ByteString -> ByteString

sconcat :: NonEmpty ByteString -> ByteString

stimes :: Integral b => b -> ByteString -> ByteString

Monoid ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

mempty :: ByteString

mappend :: ByteString -> ByteString -> ByteString

mconcat :: [ByteString] -> ByteString

Hashable ByteString

Defined in Data.Hashable.Class

Methods

hashWithSalt :: Int -> ByteString -> Int

hash :: ByteString -> Int

FoldCase ByteString

Note that foldCase on ByteStrings is only guaranteed to be correct for ISO-8859-1 encoded strings!

Defined in Data.CaseInsensitive.Internal

Methods

foldCase :: ByteString -> ByteString

foldCaseList :: [ByteString] -> [ByteString]

NFData ByteString

Defined in Data.ByteString.Lazy.Internal

Methods

rnf :: ByteString -> ()

IsByteString ByteString

Defined in Data.ByteString.Lens

Methods

packedBytes :: Iso' [Word8] ByteString

packedChars :: Iso' String ByteString

bytes :: IndexedTraversal' Int ByteString Word8

chars :: IndexedTraversal' Int ByteString Char

Ixed ByteString

Defined in Control.Lens.At

Methods

ix :: Index ByteString -> Traversal' ByteString (IxValue ByteString)

AsEmpty ByteString

Defined in Control.Lens.Empty

Methods

_Empty :: Prism' ByteString ()

Reversing ByteString

Defined in Control.Lens.Internal.Iso

Methods

reversing :: ByteString -> ByteString

AsNumber ByteString

Defined in Data.Aeson.Lens

Methods

_Number :: Prism' ByteString Scientific

_Double :: Prism' ByteString Double

_Integer :: Prism' ByteString Integer

AsPrimitive ByteString

Defined in Data.Aeson.Lens

Methods

_Primitive :: Prism' ByteString Primitive

_String :: Prism' ByteString Text

_Bool :: Prism' ByteString Bool

_Null :: Prism' ByteString ()

AsValue ByteString

Defined in Data.Aeson.Lens

Methods

_Value :: Prism' ByteString Value

_Object :: Prism' ByteString (HashMap Text Value)

_Array :: Prism' ByteString (Vector Value)

AsJSON ByteString

Defined in Data.Aeson.Lens

Methods

_JSON :: (FromJSON a, ToJSON a) => Prism' ByteString a

Stream ByteString

Defined in Text.Megaparsec.Stream

Associated Types

type Token ByteString :: *

type Tokens ByteString :: *

Methods

tokenToChunk :: Proxy ByteString -> Token ByteString -> Tokens ByteString

tokensToChunk :: Proxy ByteString -> [Token ByteString] -> Tokens ByteString

chunkToTokens :: Proxy ByteString -> Tokens ByteString -> [Token ByteString]

chunkLength :: Proxy ByteString -> Tokens ByteString -> Int

chunkEmpty :: Proxy ByteString -> Tokens ByteString -> Bool

positionAt1 :: Proxy ByteString -> SourcePos -> Token ByteString -> SourcePos

positionAtN :: Proxy ByteString -> SourcePos -> Tokens ByteString -> SourcePos

advance1 :: Proxy ByteString -> Pos -> SourcePos -> Token ByteString -> SourcePos

advanceN :: Proxy ByteString -> Pos -> SourcePos -> Tokens ByteString -> SourcePos

take1_ :: ByteString -> Maybe (Token ByteString, ByteString)

takeN_ :: Int -> ByteString -> Maybe (Tokens ByteString, ByteString)

takeWhile_ :: (Token ByteString -> Bool) -> ByteString -> (Tokens ByteString, ByteString)

Serialise ByteString

Since: serialise-0.2.0.0

Defined in Codec.Serialise.Class

Methods

encode :: ByteString -> Encoding

decode :: Decoder s ByteString

encodeList :: [ByteString] -> Encoding

decodeList :: Decoder s [ByteString]

Substitution ByteString

Defined in Data.ByteString.Search.Substitution

Methods

substitution :: ByteString -> [ByteString0] -> [ByteString0]

prependCycle :: ByteString -> ByteString -> ByteString

Strict ByteString ByteString

Defined in Control.Lens.Iso

Methods

strict :: Iso' ByteString ByteString0

(a ~ Word8, b ~ Word8) => Each ByteString ByteString a b

each :: Traversal ByteString ByteString Word8 Word8

Defined in Control.Lens.Each

Methods

each :: Traversal ByteString ByteString a b

Cons ByteString ByteString Word8 Word8

Defined in Control.Lens.Cons

Methods

_Cons :: Prism ByteString ByteString (Word8, ByteString) (Word8, ByteString)

Snoc ByteString ByteString Word8 Word8

Defined in Control.Lens.Cons

Methods

_Snoc :: Prism ByteString ByteString (ByteString, Word8) (ByteString, Word8)

type Index ByteString

Defined in Control.Lens.At

type Index ByteString = Int64

type IxValue ByteString

Defined in Control.Lens.At

type IxValue ByteString = Word8

type Tokens ByteString

Defined in Text.Megaparsec.Stream

type Tokens ByteString = ByteString

type Token ByteString

Defined in Text.Megaparsec.Stream

type Token ByteString = Word8

fromChunks :: [ByteString] -> ByteString

O(c) Convert a list of strict ByteString into a lazy ByteString

append :: ByteString -> ByteString -> ByteString

O(n/c) Append two ByteStrings

singleton :: Word8 -> ByteString

O(1) Convert a Word8 into a ByteString

empty :: ByteString

O(1) The empty ByteString

interact :: (ByteString -> ByteString) -> IO ()

The interact function takes a function of type ByteString -> ByteString as its argument. The entire input from the standard input device is passed to this function as its argument, and the resulting string is output on the standard output device.

putStrLn :: ByteString -> IO ()

Write a ByteString to stdout, appending a newline byte

putStr :: ByteString -> IO ()

Write a ByteString to stdout

hPutStr :: Handle -> ByteString -> IO ()

A synonym for hPut, for compatibility

hPutNonBlocking :: Handle -> ByteString -> IO ByteString

Similar to hPut except that it will never block. Instead it returns any tail that did not get written. This tail may be empty in the case that the whole string was written, or the whole original string if nothing was written. Partial writes are also possible.

Note: on Windows and with Haskell implementation other than GHC, this function does not work correctly; it behaves identically to hPut.

hPut :: Handle -> ByteString -> IO ()

Outputs a ByteString to the specified Handle. The chunks will be written one at a time. Other threads might write to the Handle between the writes, and hence hPut alone might not be suitable for concurrent writes.

getContents :: IO ByteString

getContents. Equivalent to hGetContents stdin. Will read lazily

appendFile :: FilePath -> ByteString -> IO ()

Append a ByteString to a file.

writeFile :: FilePath -> ByteString -> IO ()

Write a ByteString to a file.

readFile :: FilePath -> IO ByteString

Read an entire file lazily into a ByteString. The Handle will be held open until EOF is encountered.

hGetNonBlocking :: Handle -> Int -> IO ByteString

hGetNonBlocking is similar to hGet, except that it will never block waiting for data to become available, instead it returns only whatever data is available. If there is no data available to be read, hGetNonBlocking returns empty.

Note: on Windows and with Haskell implementation other than GHC, this function does not work correctly; it behaves identically to hGet.

hGet :: Handle -> Int -> IO ByteString

Read n bytes into a ByteString, directly from the specified Handle.

hGetContents :: Handle -> IO ByteString

Read entire handle contents lazily into a ByteString. Chunks are read on demand, using the default chunk size.

Once EOF is encountered, the Handle is closed.

Note: the Handle should be placed in binary mode with hSetBinaryMode for hGetContents to work correctly.

copy :: ByteString -> ByteString

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.

tails :: ByteString -> [ByteString]

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

inits :: ByteString -> [ByteString]

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

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

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

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

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)]

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.

stripSuffix :: ByteString -> ByteString -> Maybe ByteString

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.

isSuffixOf :: ByteString -> ByteString -> Bool

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

stripPrefix :: ByteString -> ByteString -> Maybe ByteString

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

isPrefixOf :: ByteString -> ByteString -> Bool

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

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

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)

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

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

notElem :: Word8 -> ByteString -> Bool

O(n) notElem is the inverse of elem

elem :: Word8 -> ByteString -> Bool

O(n) elem is the ByteString membership predicate.

findIndices :: (Word8 -> Bool) -> ByteString -> [Int64]

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

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

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

findIndex :: (Word8 -> Bool) -> ByteString -> Maybe Int64

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

count :: Word8 -> ByteString -> Int64

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.

elemIndices :: Word8 -> ByteString -> [Int64]

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 Int64

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)

Since: bytestring-0.10.6.0

elemIndex :: Word8 -> ByteString -> Maybe Int64

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).

index :: ByteString -> Int64 -> Word8

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

intercalate :: ByteString -> [ByteString] -> ByteString

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.

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

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

group :: ByteString -> [ByteString]

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.

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

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

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

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

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

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

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

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

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

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

splitAt :: Int64 -> ByteString -> (ByteString, ByteString)

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

drop :: Int64 -> ByteString -> ByteString

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

take :: Int64 -> ByteString -> ByteString

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

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

O(n) 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 a prepending to the ByteString and b is used as the next element in a recursive call.

cycle :: ByteString -> ByteString

cycle ties a finite ByteString into a circular one, or equivalently, the infinite repetition of the original ByteString.

replicate :: Int64 -> Word8 -> ByteString

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

repeat :: Word8 -> ByteString

repeat x is an infinite ByteString, with x the value of every element.

iterate :: (Word8 -> Word8) -> Word8 -> ByteString

iterate f x returns an infinite ByteString of repeated applications of f to x:

iterate f x == [x, f x, f (f x), ...]

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

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.

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

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)

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 ByteString.

minimum :: ByteString -> Word8

O(n) minimum returns the minimum value from a ByteString

maximum :: ByteString -> Word8

O(n) maximum returns the maximum value from a ByteString

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

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

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

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

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

Map a function over a ByteString and concatenate the results

concat :: [ByteString] -> ByteString

O(n) Concatenate a list of ByteStrings.

foldr1 :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8

foldr1 is a variant of foldr that has no starting value argument, and thus must be applied to non-empty ByteStrings

foldl1' :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8

'foldl1\'' is like foldl1, but strict in the accumulator.

foldl1 :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8

foldl1 is a variant of foldl that has no starting value argument, and thus must be applied to non-empty ByteStrings.

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

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

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

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

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.

transpose :: [ByteString] -> [ByteString]

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

intersperse :: Word8 -> ByteString -> ByteString

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.

reverse :: ByteString -> ByteString

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

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

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

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

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

• It is no faster than using init and last

init :: ByteString -> ByteString

O(n/c) Return all the elements of a ByteString except the last one.

last :: ByteString -> Word8

O(n/c) Extract the last element of a ByteString, which must be finite and non-empty.

tail :: ByteString -> ByteString

O(1) Extract the elements after the head of a ByteString, which must be non-empty.

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

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

head :: ByteString -> Word8

O(1) Extract the first element of a ByteString, which must be non-empty.

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

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

cons' :: Word8 -> ByteString -> ByteString infixr 5

O(1) Unlike cons, 'cons\'' is strict in the ByteString that we are consing onto. More precisely, it forces the head and the first chunk. It does this because, for space efficiency, it may coalesce the new byte onto the first 'chunk' rather than starting a new 'chunk'.

So that means you can't use a lazy recursive contruction like this:

let xs = cons\' c xs in xs

You can however use cons, as well as repeat and cycle, to build infinite lazy ByteStrings.

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

O(1) cons is analogous to '(:)' for lists.

length :: ByteString -> Int64

O(n/c) length returns the length of a ByteString as an Int64

null :: ByteString -> Bool

O(1) Test whether a ByteString is empty.

toStrict :: ByteString -> ByteString

O(n) Convert a lazy ByteString into a strict ByteString.

Note that this is an expensive operation that forces the whole lazy ByteString into memory and then copies all the data. If possible, try to avoid converting back and forth between strict and lazy bytestrings.

fromStrict :: ByteString -> ByteString

O(1) Convert a strict ByteString into a lazy ByteString.

toChunks :: ByteString -> [ByteString]

O(c) Convert a lazy ByteString into a list of strict ByteString

unpack :: ByteString -> [Word8]

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

pack :: [Word8] -> ByteString

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

foldlChunks :: (a -> ByteString -> a) -> a -> ByteString -> a

Consume the chunks of a lazy ByteString with a strict, tail-recursive, accumulating left fold.

foldrChunks :: (ByteString -> a -> a) -> a -> ByteString -> a

Consume the chunks of a lazy ByteString with a natural right fold.

breakAfter

Arguments

:: ByteString

Strict pattern to search for

-> ByteString

Lazy string to search in

-> (ByteString, ByteString)

Head and tail of string broken after substring

breakAfter pattern target splits target behind the first occurrence of pattern. An empty second component means that either the pattern does not occur in the target or the first occurrence of pattern is at the very end of target. If you need to discriminate between those cases, use breakFindAfter. If the pattern is empty, the first component is empty. For a non-empty pattern, the first component is generated lazily, thus the first parts of it can be available before the pattern has been found or determined to be absent.

  uncurry append . breakAfter pattern = id

breakFindAfter

Arguments

:: ByteString

Strict pattern to search for

-> ByteString

Lazy string to search in

-> ((ByteString, ByteString), Bool)

Head and tail of string broken after substring and presence of pattern

breakFindAfter does the same as breakAfter but additionally indicates whether the pattern is present in the target.

  fst . breakFindAfter pat = breakAfter pat

breakOn

Arguments

:: ByteString

Strict pattern to search for

-> ByteString

Lazy string to search in

-> (ByteString, ByteString)

Head and tail of string broken at substring

breakOn pattern target splits target at the first occurrence of pattern. If the pattern does not occur in the target, the second component of the result is empty, otherwise it starts with pattern. If the pattern is empty, the first component is empty. For a non-empty pattern, the first component is generated lazily, thus the first parts of it can be available before the pattern has been found or determined to be absent.

  uncurry append . breakOn pattern = id

indices

Arguments

:: ByteString

Strict pattern to find

-> ByteString

Lazy string to search

-> [Int64]

Offsets of matches

indices finds the starting indices of all possibly overlapping occurrences of the pattern in the target string. If the pattern is empty, the result is [0 .. length target].

nonOverlappingIndices

Arguments

:: ByteString

Strict pattern to find

-> ByteString

Lazy string to search

-> [Int64]

Offsets of matches

nonOverlappingIndices finds the starting indices of all non-overlapping occurrences of the pattern in the target string. It is more efficient than removing indices from the list produced by indices.

replace

Arguments

:: Substitution rep

=> ByteString

Strict pattern to replace

-> rep

Replacement string

-> ByteString

Lazy string to modify

-> ByteString

Lazy result

replace pat sub text replaces all (non-overlapping) occurrences of pat in text with sub. If occurrences of pat overlap, the first occurrence that does not overlap with a replaced previous occurrence is substituted. Occurrences of pat arising from a substitution will not be substituted. For example:

  replace "ana" "olog" "banana" = "bologna"
  replace "ana" "o" "bananana" = "bono"
  replace "aab" "abaa" "aaabb" = "aabaab"

The result is a lazy ByteString, which is lazily produced, without copying. Equality of pattern and substitution is not checked, but

  replace pat pat text == text

holds (the internal structure is generally different). If the pattern is empty but not the substitution, the result is equivalent to (were they Strings) cycle sub.

For non-empty pat and sub a lazy ByteString,

  concat . intersperse sub . split pat = replace pat sub

and analogous relations hold for other types of sub.

split

Arguments

:: ByteString

Strict pattern to split on

-> ByteString

Lazy string to split

-> [ByteString]

Fragments of string

split pattern target splits target at each (non-overlapping) occurrence of pattern, removing pattern. If pattern is empty, the result is an infinite list of empty ByteStrings, if target is empty but not pattern, the result is an empty list, otherwise the following relations hold (where patL is the lazy ByteString corresponding to pat):

  concat . intersperse patL . split pat = id,
  length (split pattern target) ==
              length (nonOverlappingIndices pattern target) + 1,

no fragment in the result contains an occurrence of pattern.

splitKeepEnd

Arguments

:: ByteString

Strict pattern to split on

-> ByteString

Lazy string to split

-> [ByteString]

Fragments of string

splitKeepEnd pattern target splits target after each (non-overlapping) occurrence of pattern. If pattern is empty, the result is an infinite list of empty ByteStrings, otherwise the following relations hold:

  concat . splitKeepEnd pattern = id,

all fragments in the result except possibly the last end with pattern, no fragment contains more than one occurrence of pattern.

splitKeepFront

Arguments

:: ByteString

Strict pattern to split on

-> ByteString

Lazy string to split

-> [ByteString]

Fragments of string

splitKeepFront is like splitKeepEnd, except that target is split before each occurrence of pattern and hence all fragments with the possible exception of the first begin with pattern. No fragment contains more than one non-overlapping occurrence of pattern.

Optics

bytes :: IsByteString t => IndexedTraversal' Int t Word8

Traverse each Word8 in a strict or lazy ByteString

This Traversal walks each strict ByteString chunk in a tree-like fashion enable zippers to seek to locations more quickly and accelerate many monoidal queries, but up to associativity (and constant factors) it is equivalent to the much slower:

bytes ≡ unpackedBytes . traversed

anyOf bytes (== 0x80) :: ByteString -> Bool

packedBytes :: IsByteString t => Iso' [Word8] t

pack (or unpack) a list of bytes into a strict or lazy ByteString.

pack x ≡ x ^. packedBytes
unpack x ≡ x ^. from packedBytes
packedBytes ≡ from unpackedBytes

unpackedBytes :: IsByteString t => Iso' t [Word8]

unpack (or pack) a ByteString into a list of bytes

unpackedBytes ≡ from packedBytes
unpack x ≡ x ^. unpackedBytes
pack x ≡  x ^. from unpackedBytes

unpackedBytes :: Iso' ByteString [Word8]
unpackedBytes :: Iso' ByteString [Word8]