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ByteStringUtils

Portability | portable
Stability | experimental
Maintainer | droundy@abridgegame.org

Description
GZIp and MMap IO for ByteStrings, and miscellaneous functions for Data.ByteString
Synopsis

unsafeWithInternals :: ByteString -> (Ptr Word8 -> Int -> IO a) -> IO a
gzReadFilePS :: FilePath -> IO ByteString
mmapFilePS :: FilePath -> IO ByteString
gzWriteFilePS :: FilePath -> ByteString -> IO ()
gzWriteFilePSs :: FilePath -> [ByteString] -> IO ()
isGZFile :: FilePath -> IO (Maybe Int)
gzDecompress :: Maybe Int -> ByteString -> ([ByteString], Bool)
ifHeadThenTail :: Word8 -> ByteString -> Maybe ByteString
dropSpace :: ByteString -> ByteString
breakSpace :: ByteString -> (ByteString, ByteString)
linesPS :: ByteString -> [ByteString]
unlinesPS :: [ByteString] -> ByteString
hashPS :: ByteString -> Int32
breakFirstPS :: Char -> ByteString -> Maybe (ByteString, ByteString)
breakLastPS :: Char -> ByteString -> Maybe (ByteString, ByteString)
substrPS :: ByteString -> ByteString -> Maybe Int
readIntPS :: ByteString -> Maybe (Int, ByteString)
is_funky :: ByteString -> Bool
fromHex2PS :: ByteString -> ByteString
fromPS2Hex :: ByteString -> ByteString
betweenLinesPS :: ByteString -> ByteString -> ByteString -> Maybe ByteString
break_after_nth_newline :: Int -> ByteString -> Maybe (ByteString, ByteString)
break_before_nth_newline :: Int -> ByteString -> (ByteString, ByteString)
intercalate

Documentation

unsafeWithInternals :: ByteString -> (Ptr Word8 -> Int -> IO a) -> IO a | Source

Do something with the internals of a PackedString. Beware of altering the contents!

gzReadFilePS :: FilePath -> IO ByteString | Source

Read an entire file, which may or may not be gzip compressed, directly into a `ByteString`.

mmapFilePS :: FilePath -> IO ByteString | Source

Like readFilePS, this reads an entire file directly into a `ByteString`, but it is even more efficient. It involves directly mapping the file to memory. This has the advantage that the contents of the file never need to be copied. Also, under memory pressure the page may simply be discarded, wile in the case of readFilePS it would need to be written to swap. If you read many small files, mmapFilePS will be less memory-efficient than readFilePS, since each mmapFilePS takes up a separate page of memory. Also, you can run into bus errors if the file is modified. NOTE: as with readFilePS, the string representation in the file is assumed to be ISO-8859-1.

gzWriteFilePS :: FilePath -> ByteString -> IO () | Source

gzWriteFilePSs :: FilePath -> [ByteString] -> IO () | Source

isGZFile :: FilePath -> IO (Maybe Int) | Source

gzDecompress :: Maybe Int -> ByteString -> ([ByteString], Bool) | Source

Decompress the given bytestring into a lazy list of chunks, along with a boolean flag indicating (if True) that the CRC was corrupted. Inspecting the flag will cause the entire list of chunks to be evaluated (but if you throw away the list immediately this should run in constant space).

ifHeadThenTail :: Word8 -> ByteString -> Maybe ByteString | Source

dropSpace :: ByteString -> ByteString | Source

`dropSpace` efficiently returns the ByteString argument with white space Chars removed from the front. It is more efficient than calling dropWhile for removing whitespace. I.e.

     dropWhile isSpace == dropSpace

breakSpace :: ByteString -> (ByteString, ByteString) | Source

`breakSpace` returns the pair of ByteStrings when the argument is broken at the first whitespace byte. I.e.

     break isSpace == breakSpace

linesPS :: ByteString -> [ByteString] | Source

unlinesPS :: [ByteString] -> ByteString | Source

This function acts exactly like the Prelude unlines function, or like Data.ByteString.Char8 `unlines`, but with one important difference: it will produce a string which may not end with a newline! That is:

     unlinesPS ["foo", "bar"]

evaluates to "foo\nbar", not "foo\nbar\n"! This point should hold true for `linesPS` as well.

TODO: rename this function.

hashPS :: ByteString -> Int32 | Source

breakFirstPS :: Char -> ByteString -> Maybe (ByteString, ByteString) | Source

breakLastPS :: Char -> ByteString -> Maybe (ByteString, ByteString) | Source

substrPS :: ByteString -> ByteString -> Maybe Int | Source

readIntPS :: ByteString -> Maybe (Int, ByteString) | Source

readIntPS skips any whitespace at the beginning of its argument, and reads an Int from the beginning of the PackedString. If there is no integer at the beginning of the string, it returns Nothing, otherwise it just returns the int read, along with a B.ByteString containing the remainder of its input.

is_funky :: ByteString -> Bool | Source

fromHex2PS :: ByteString -> ByteString | Source

fromPS2Hex :: ByteString -> ByteString | Source

betweenLinesPS :: ByteString -> ByteString -> ByteString -> Maybe ByteString | Source

betweenLinesPS returns the B.ByteString between the two lines given, or Nothing if they do not appear.

break_after_nth_newline :: Int -> ByteString -> Maybe (ByteString, ByteString) | Source

break_before_nth_newline :: Int -> ByteString -> (ByteString, ByteString) | Source

intercalate
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