Copyright | (c) XT 2016 |
---|---|
License | Apache 2.0 |
Maintainer | e@xtendo.org |
Stability | stable |
Portability | POSIX |
Safe Haskell | Safe-Inferred |
Language | Haskell2010 |
A drop-in replacement of Data.ByteString
from the bytestring
package
that provides file I/O functions with RawFilePath
instead of FilePath
.
Synopsis
- zipWith :: (Word8 -> Word8 -> a) -> ByteString -> ByteString -> [a]
- zip :: ByteString -> ByteString -> [(Word8, Word8)]
- useAsCStringLen :: ByteString -> (CStringLen -> IO a) -> IO a
- useAsCString :: ByteString -> (CString -> IO a) -> IO a
- unzip :: [(Word8, Word8)] -> (ByteString, ByteString)
- unsnoc :: ByteString -> Maybe (ByteString, Word8)
- unpack :: ByteString -> [Word8]
- unfoldrN :: Int -> (a -> Maybe (Word8, a)) -> a -> (ByteString, Maybe a)
- unfoldr :: (a -> Maybe (Word8, a)) -> a -> ByteString
- uncons :: ByteString -> Maybe (Word8, ByteString)
- transpose :: [ByteString] -> [ByteString]
- toFilePath :: ByteString -> IO FilePath
- takeWhileEnd :: (Word8 -> Bool) -> ByteString -> ByteString
- takeWhile :: (Word8 -> Bool) -> ByteString -> ByteString
- takeEnd :: Int -> ByteString -> ByteString
- take :: Int -> ByteString -> ByteString
- tails :: ByteString -> [ByteString]
- tail :: HasCallStack => ByteString -> ByteString
- stripSuffix :: ByteString -> ByteString -> Maybe ByteString
- stripPrefix :: ByteString -> ByteString -> Maybe ByteString
- splitWith :: (Word8 -> Bool) -> ByteString -> [ByteString]
- splitAt :: Int -> ByteString -> (ByteString, ByteString)
- split :: Word8 -> ByteString -> [ByteString]
- spanEnd :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
- span :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
- sort :: ByteString -> ByteString
- snoc :: ByteString -> Word8 -> ByteString
- singleton :: Word8 -> ByteString
- scanr1 :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString
- scanr :: (Word8 -> Word8 -> Word8) -> Word8 -> ByteString -> ByteString
- scanl1 :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString
- scanl :: (Word8 -> Word8 -> Word8) -> Word8 -> ByteString -> ByteString
- reverse :: ByteString -> ByteString
- replicate :: Int -> Word8 -> ByteString
- putStr :: ByteString -> IO ()
- partition :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
- packZipWith :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString -> ByteString
- packCStringLen :: CStringLen -> IO ByteString
- packCString :: CString -> IO ByteString
- pack :: [Word8] -> ByteString
- null :: ByteString -> Bool
- notElem :: Word8 -> ByteString -> Bool
- minimum :: HasCallStack => ByteString -> Word8
- maximum :: HasCallStack => ByteString -> Word8
- mapAccumR :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString)
- mapAccumL :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString)
- map :: (Word8 -> Word8) -> ByteString -> ByteString
- length :: ByteString -> Int
- last :: HasCallStack => ByteString -> Word8
- isValidUtf8 :: ByteString -> Bool
- isSuffixOf :: ByteString -> ByteString -> Bool
- isPrefixOf :: ByteString -> ByteString -> Bool
- isInfixOf :: ByteString -> ByteString -> Bool
- intersperse :: Word8 -> ByteString -> ByteString
- intercalate :: ByteString -> [ByteString] -> ByteString
- interact :: (ByteString -> ByteString) -> IO ()
- inits :: ByteString -> [ByteString]
- init :: HasCallStack => ByteString -> ByteString
- indexMaybe :: ByteString -> Int -> Maybe Word8
- index :: HasCallStack => ByteString -> Int -> Word8
- head :: HasCallStack => ByteString -> Word8
- hPutStr :: Handle -> ByteString -> IO ()
- hPutNonBlocking :: Handle -> ByteString -> IO ByteString
- hPut :: Handle -> ByteString -> IO ()
- hGetSome :: Handle -> Int -> IO ByteString
- hGetNonBlocking :: Handle -> Int -> IO ByteString
- hGetLine :: Handle -> IO ByteString
- hGetContents :: Handle -> IO ByteString
- hGet :: Handle -> Int -> IO ByteString
- groupBy :: (Word8 -> Word8 -> Bool) -> ByteString -> [ByteString]
- group :: ByteString -> [ByteString]
- getLine :: IO ByteString
- getContents :: IO ByteString
- fromFilePath :: FilePath -> IO ByteString
- foldr1' :: HasCallStack => (Word8 -> Word8 -> Word8) -> ByteString -> Word8
- foldr1 :: HasCallStack => (Word8 -> Word8 -> Word8) -> ByteString -> Word8
- foldr' :: (Word8 -> a -> a) -> a -> ByteString -> a
- foldr :: (Word8 -> a -> a) -> a -> ByteString -> a
- foldl1' :: HasCallStack => (Word8 -> Word8 -> Word8) -> ByteString -> Word8
- foldl1 :: HasCallStack => (Word8 -> Word8 -> Word8) -> ByteString -> Word8
- foldl' :: (a -> Word8 -> a) -> a -> ByteString -> a
- foldl :: (a -> Word8 -> a) -> a -> ByteString -> a
- findIndices :: (Word8 -> Bool) -> ByteString -> [Int]
- findIndexEnd :: (Word8 -> Bool) -> ByteString -> Maybe Int
- findIndex :: (Word8 -> Bool) -> ByteString -> Maybe Int
- find :: (Word8 -> Bool) -> ByteString -> Maybe Word8
- filter :: (Word8 -> Bool) -> ByteString -> ByteString
- elemIndices :: Word8 -> ByteString -> [Int]
- elemIndexEnd :: Word8 -> ByteString -> Maybe Int
- elemIndex :: Word8 -> ByteString -> Maybe Int
- elem :: Word8 -> ByteString -> Bool
- dropWhileEnd :: (Word8 -> Bool) -> ByteString -> ByteString
- dropWhile :: (Word8 -> Bool) -> ByteString -> ByteString
- dropEnd :: Int -> ByteString -> ByteString
- drop :: Int -> ByteString -> ByteString
- count :: Word8 -> ByteString -> Int
- copy :: ByteString -> ByteString
- cons :: Word8 -> ByteString -> ByteString
- concatMap :: (Word8 -> ByteString) -> ByteString -> ByteString
- concat :: [ByteString] -> ByteString
- breakSubstring :: ByteString -> ByteString -> (ByteString, ByteString)
- breakEnd :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
- break :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
- append :: ByteString -> ByteString -> ByteString
- any :: (Word8 -> Bool) -> ByteString -> Bool
- all :: (Word8 -> Bool) -> ByteString -> Bool
- (!?) :: ByteString -> Int -> Maybe Word8
- toStrict :: ByteString -> ByteString
- fromStrict :: ByteString -> ByteString
- type StrictByteString = ByteString
- data ByteString
- empty :: ByteString
- type RawFilePath = ByteString
- readFile :: RawFilePath -> IO ByteString
- writeFile :: RawFilePath -> ByteString -> IO ()
- appendFile :: RawFilePath -> ByteString -> IO ()
- withFile :: RawFilePath -> IOMode -> (Handle -> IO r) -> IO r
Documentation
zipWith :: (Word8 -> Word8 -> a) -> ByteString -> ByteString -> [a] #
zip :: ByteString -> ByteString -> [(Word8, Word8)] #
useAsCStringLen :: ByteString -> (CStringLen -> IO a) -> IO a #
O(n) construction Use a ByteString
with a function requiring a CStringLen
.
As for useAsCString
this function makes a copy of the original ByteString
.
It must not be stored or used after the subcomputation finishes.
useAsCString :: ByteString -> (CString -> IO a) -> IO a #
O(n) construction Use a ByteString
with a function requiring a
null-terminated CString
. The CString
is a copy and will be freed
automatically; it must not be stored or used after the
subcomputation finishes.
unzip :: [(Word8, Word8)] -> (ByteString, ByteString) #
unsnoc :: ByteString -> Maybe (ByteString, Word8) #
unpack :: ByteString -> [Word8] #
O(n) Converts a ByteString
to a [
.Word8
]
unfoldrN :: Int -> (a -> Maybe (Word8, a)) -> a -> (ByteString, Maybe a) #
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 #
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) #
O(1) Extract the head and tail of a ByteString, returning Nothing if it is empty.
transpose :: [ByteString] -> [ByteString] #
The transpose
function transposes the rows and columns of its
ByteString
argument.
toFilePath :: ByteString -> IO FilePath #
Convert a ByteString
to a FilePath
.
This function uses the file system encoding, and resulting FilePath
s
can be safely used with standard IO functions and will reference the
correct path in the presence of arbitrary non-UTF-8 encoded paths.
This function is in IO
because the file system encoding can be
changed. If the encoding can be assumed to be constant in your
use case, you may invoke this function via unsafePerformIO
.
Since: bytestring-0.11.2.0
takeWhileEnd :: (Word8 -> Bool) -> ByteString -> ByteString #
Returns the longest (possibly empty) suffix of elements satisfying the predicate.
is equivalent to takeWhileEnd
p
.reverse
. takeWhile
p . reverse
Since: bytestring-0.10.12.0
takeWhile :: (Word8 -> Bool) -> ByteString -> ByteString #
Similar to takeWhile
,
returns the longest (possibly empty) prefix of elements
satisfying the predicate.
takeEnd :: Int -> ByteString -> ByteString #
take :: Int -> ByteString -> ByteString #
tails :: ByteString -> [ByteString] #
O(n) Return all final segments of the given ByteString
, longest first.
tail :: HasCallStack => ByteString -> ByteString #
O(1) Extract the elements after the head of a ByteString, which must be non-empty. An exception will be thrown in the case of an empty ByteString.
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
.
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
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 (==97) "aabbaca" == ["","","bb","c",""] -- fromEnum 'a' == 97 splitWith undefined "" == [] -- and not [""]
splitAt :: Int -> ByteString -> (ByteString, ByteString) #
split :: Word8 -> ByteString -> [ByteString] #
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 split undefined "" == [] -- and not [""]
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 ByteString
s that
are slices of the original.
spanEnd :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString) #
Returns the longest (possibly empty) suffix of elements satisfying the predicate and the remainder of the string.
spanEnd
p
is equivalent to
and to breakEnd
(not . p)(
.takeWhileEnd
p &&& dropWhileEnd
p)
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) #
sort :: ByteString -> ByteString #
O(n) Sort a ByteString efficiently, using counting sort.
snoc :: ByteString -> Word8 -> ByteString infixl 5 #
O(n) Append a byte to the end of a ByteString
singleton :: Word8 -> ByteString #
O(1) Convert a Word8
into a ByteString
scanr1 :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString #
:: (Word8 -> Word8 -> Word8) | element -> accumulator -> new accumulator |
-> Word8 | starting value of accumulator |
-> ByteString | input of length n |
-> ByteString | output of length n+1 |
scanl1 :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString #
:: (Word8 -> Word8 -> Word8) | accumulator -> element -> new accumulator |
-> Word8 | starting value of accumulator |
-> ByteString | input of length n |
-> ByteString | output of length n+1 |
reverse :: ByteString -> ByteString #
O(n) reverse
xs
efficiently returns the elements of xs
in reverse order.
replicate :: Int -> Word8 -> ByteString #
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 implementation uses memset(3)
putStr :: ByteString -> IO () #
Write a ByteString to stdout
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)
packZipWith :: (Word8 -> Word8 -> Word8) -> ByteString -> ByteString -> ByteString #
A specialised version of zipWith
for the common case of a
simultaneous map over two ByteStrings, to build a 3rd.
Since: bytestring-0.11.1.0
packCStringLen :: CStringLen -> IO ByteString #
O(n). Construct a new ByteString
from a CStringLen
. The
resulting ByteString
is an immutable copy of the original CStringLen
.
The ByteString
is a normal Haskell value and will be managed on the
Haskell heap.
packCString :: CString -> IO ByteString #
O(n). Construct a new ByteString
from a CString
. The
resulting ByteString
is an immutable copy of the original
CString
, and is managed on the Haskell heap. The original
CString
must be null terminated.
pack :: [Word8] -> ByteString #
O(n) Convert a [
into a Word8
]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 #
O(1) Test whether a ByteString is empty.
minimum :: HasCallStack => ByteString -> Word8 #
O(n) minimum
returns the minimum value from a ByteString
An exception will be thrown in the case of an empty ByteString.
maximum :: HasCallStack => ByteString -> Word8 #
O(n) maximum
returns the maximum value from a ByteString
An exception will be thrown in the case of an empty ByteString.
mapAccumR :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString) #
mapAccumL :: (acc -> Word8 -> (acc, Word8)) -> acc -> ByteString -> (acc, ByteString) #
map :: (Word8 -> Word8) -> ByteString -> ByteString #
O(n) map
f xs
is the ByteString obtained by applying f
to each
element of xs
.
last :: HasCallStack => ByteString -> Word8 #
O(1) Extract the last element of a ByteString, which must be finite and non-empty. An exception will be thrown in the case of an empty ByteString.
isValidUtf8 :: ByteString -> Bool #
O(n) Check whether a ByteString
represents valid UTF-8.
Since: bytestring-0.11.2.0
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
However, the real implementation uses memcmp to compare the end of the string only, with no reverse required..
isPrefixOf :: ByteString -> ByteString -> Bool #
O(n) The isPrefixOf
function takes two ByteStrings and returns True
if the first is a prefix of the second.
isInfixOf :: ByteString -> ByteString -> Bool #
Check whether one string is a substring of another.
intersperse :: Word8 -> ByteString -> ByteString #
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 #
O(n) The intercalate
function takes a ByteString
and a list of
ByteString
s and concatenates the list after interspersing the first
argument between each element of the list.
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.
inits :: ByteString -> [ByteString] #
O(n) Return all initial segments of the given ByteString
, shortest first.
init :: HasCallStack => ByteString -> ByteString #
O(1) Return all the elements of a ByteString
except the last one.
An exception will be thrown in the case of an empty ByteString.
indexMaybe :: ByteString -> Int -> Maybe Word8 #
O(1) ByteString
index, starting from 0, that returns Just
if:
0 <= n < length bs
Since: bytestring-0.11.0.0
index :: HasCallStack => ByteString -> Int -> Word8 #
O(1) ByteString
index (subscript) operator, starting from 0.
head :: HasCallStack => ByteString -> Word8 #
O(1) Extract the first element of a ByteString, which must be non-empty. An exception will be thrown in the case of an empty ByteString.
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
.
hGetSome :: Handle -> Int -> IO ByteString #
Like hGet
, except that a shorter ByteString
may be returned
if there are not enough bytes immediately available to satisfy the
whole request. hGetSome
only blocks if there is no data
available, and EOF has not yet been reached.
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
.
hGetLine :: Handle -> IO ByteString #
Read a line from a handle
hGetContents :: Handle -> IO ByteString #
Read a handle's entire contents strictly into a ByteString
.
This function reads chunks at a time, increasing the chunk size on each
read. The final string is then reallocated to the appropriate size. For
files > half of available memory, this may lead to memory exhaustion.
Consider using readFile
in this case.
The Handle is closed once the contents have been read, or if an exception is thrown.
hGet :: Handle -> Int -> IO ByteString #
Read a ByteString
directly from the specified Handle
. This
is far more efficient than reading the characters into a String
and then using pack
. First argument is the Handle to read from,
and the second is the number of bytes to read. It returns the bytes
read, up to n, or empty
if EOF has been reached.
hGet
is implemented in terms of hGetBuf
.
If the handle is a pipe or socket, and the writing end
is closed, hGet
will behave as if EOF was reached.
groupBy :: (Word8 -> Word8 -> Bool) -> ByteString -> [ByteString] #
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 string 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 (==)
getLine :: IO ByteString #
Read a line from stdin.
getContents :: IO ByteString #
getContents. Read stdin strictly. Equivalent to hGetContents stdin
The Handle
is closed after the contents have been read.
fromFilePath :: FilePath -> IO ByteString #
Convert a FilePath
to a ByteString
.
The FilePath
type is expected to use the file system encoding
as reported by getFileSystemEncoding
. This
encoding allows for round-tripping of arbitrary data on platforms
that allow arbitrary bytes in their paths. This conversion
function does the same thing that openFile
would
do when decoding the FilePath
.
This function is in IO
because the file system encoding can be
changed. If the encoding can be assumed to be constant in your
use case, you may invoke this function via unsafePerformIO
.
Since: bytestring-0.11.2.0
foldr1' :: HasCallStack => (Word8 -> Word8 -> Word8) -> ByteString -> Word8 #
foldr1 :: HasCallStack => (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 ByteString
s
An exception will be thrown in the case of an empty ByteString.
foldr' :: (Word8 -> a -> a) -> a -> ByteString -> a #
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.
foldl1' :: HasCallStack => (Word8 -> Word8 -> Word8) -> ByteString -> Word8 #
foldl1 :: HasCallStack => (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 ByteString
s.
An exception will be thrown in the case of an empty ByteString.
foldl' :: (a -> Word8 -> a) -> a -> ByteString -> a #
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.
findIndices :: (Word8 -> Bool) -> ByteString -> [Int] #
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 #
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 #
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.
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.
elemIndices :: Word8 -> ByteString -> [Int] #
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 #
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 = case elemIndex c (reverse xs) of Nothing -> Nothing Just i -> Just (length xs - 1 - i)
elemIndex :: Word8 -> ByteString -> Maybe Int #
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 #
O(n) elem
is the ByteString
membership predicate.
dropWhileEnd :: (Word8 -> Bool) -> ByteString -> ByteString #
Similar to dropWhileEnd
,
drops the longest (possibly empty) suffix of elements
satisfying the predicate and returns the remainder.
is equivalent to dropWhileEnd
p
.reverse
. dropWhile
p . reverse
Since: bytestring-0.10.12.0
dropWhile :: (Word8 -> Bool) -> ByteString -> ByteString #
Similar to dropWhile
,
drops the longest (possibly empty) prefix of elements
satisfying the predicate and returns the remainder.
dropEnd :: Int -> ByteString -> ByteString #
drop :: Int -> ByteString -> ByteString #
count :: Word8 -> ByteString -> Int #
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 #
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 #
O(n) cons
is analogous to (:) for lists, but of different
complexity, as it requires making a copy.
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.
:: 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
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 occurrence 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) #
Returns the longest (possibly empty) suffix of elements which do not satisfy the predicate and the remainder of the string.
breakEnd
p
is equivalent to
and to spanEnd
(not . p)(
.takeWhileEnd
(not . p) &&& dropWhileEnd
(not . p))
break :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString) #
Similar to break
,
returns the longest (possibly empty) prefix of elements which do not
satisfy the predicate and the remainder of the string.
break
p
is equivalent to
and to span
(not . p)(
.takeWhile
(not . p) &&& dropWhile
(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 #
O(n) Append two ByteStrings
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.
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.
(!?) :: ByteString -> Int -> Maybe Word8 #
O(1) ByteString
index, starting from 0, that returns Just
if:
0 <= n < length bs
Since: bytestring-0.11.0.0
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
.
type StrictByteString = ByteString #
Type synonym for the strict flavour of ByteString
.
Since: bytestring-0.11.2.0
data ByteString #
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
empty :: ByteString #
O(1) The empty ByteString
type RawFilePath = ByteString #
A literal POSIX file path
readFile :: RawFilePath -> IO ByteString Source #
Read an entire file at the RawFilePath
strictly into a ByteString
.
writeFile :: RawFilePath -> ByteString -> IO () Source #
Write a ByteString
to a file at the RawFilePath
.
appendFile :: RawFilePath -> ByteString -> IO () Source #
Append a ByteString
to a file at the RawFilePath
.