Data.PackedString

This API is deprecated. You might be able to use Data.ByteString or Data.ByteString.Char8 from the bytestring package, provided you don't need full Unicode support. The long term aim is to provide a Unicode layer on Data.ByteString, and then to provide a replacement for this Data.PackedString API based on that.

The PackedString type

data PackedString

A space-efficient representation of a String, which supports various efficient operations. A PackedString contains full Unicode Chars.

Instances

Eq PackedString

Data PackedString

Ord PackedString

Show PackedString

Typeable PackedString

Converting to and from PackedStrings

packString :: String -> PackedString

Convert a String into a PackedString

unpackPS :: PackedString -> String

Convert a PackedString into a String

I/O with PackedStrings

hPutPS :: Handle -> PackedString -> IO ()

Outputs a PackedString to the specified Handle.

NOTE: the representation of the PackedString in the file is assumed to be in the ISO-8859-1 encoding. In other words, only the least significant byte is taken from each character in the PackedString.

hGetPS :: Handle -> Int -> IO PackedString

Read a PackedString directly from the specified Handle. This is far more efficient than reading the characters into a String and then using packString.

NOTE: as with hPutPS, the string representation in the file is assumed to be ISO-8859-1.

List-like manipulation functions

nilPS :: PackedString

The nilPS value is the empty string.

consPS :: Char -> PackedString -> PackedString

The consPS function prepends the given character to the given string.

headPS :: PackedString -> Char

The headPS function returns the first element of a PackedString or throws an error if the string is empty.

tailPS :: PackedString -> PackedString

The tailPS function returns the tail of a PackedString or throws an error if the string is empty.

nullPS :: PackedString -> Bool

The nullPS function returns True iff the argument is null.

appendPS :: PackedString -> PackedString -> PackedString

The appendPS function appends the second string onto the first.

lengthPS :: PackedString -> Int

The lengthPS function returns the length of the input list. Analogous to length.

indexPS :: PackedString -> Int -> Char

The indexPS function returns the character in the string at the given position.

mapPS :: (Char -> Char) -> PackedString -> PackedString

The mapPS function applies a function to each character in the string.

filterPS :: (Char -> Bool) -> PackedString -> PackedString

The filterPS function filters out the appropriate substring.

reversePS :: PackedString -> PackedString

The reversePS function reverses the string.

concatPS :: [PackedString] -> PackedString

The concatPS function concatenates a list of PackedStrings.

elemPS :: Char -> PackedString -> Bool

The elemPS function returns True iff the given element is in the string.

substrPS :: PackedString -> Int -> Int -> PackedString

The substrPS function takes a PackedString and two indices and returns the substring of the input string between (and including) these indices.

takePS :: Int -> PackedString -> PackedString

The takePS function takes the first n characters of a PackedString.

dropPS :: Int -> PackedString -> PackedString

The dropPS function drops the first n characters of a PackedString.

splitAtPS :: Int -> PackedString -> (PackedString, PackedString)

The splitWithPS function splits a PackedString at a given index.

foldlPS :: (a -> Char -> a) -> a -> PackedString -> a

The foldlPS function behaves like foldl on PackedStrings.

foldrPS :: (Char -> a -> a) -> a -> PackedString -> a

The foldrPS function behaves like foldr on PackedStrings.

takeWhilePS :: (Char -> Bool) -> PackedString -> PackedString

The takeWhilePS function is analogous to the takeWhile function.

dropWhilePS :: (Char -> Bool) -> PackedString -> PackedString

The dropWhilePS function is analogous to the dropWhile function.

spanPS :: (Char -> Bool) -> PackedString -> (PackedString, PackedString)

The spanPS function returns a pair containing the result of running both takeWhilePS and dropWhilePS.

breakPS :: (Char -> Bool) -> PackedString -> (PackedString, PackedString)

The breakPS function breaks a string at the first position which satisfies the predicate.

linesPS :: PackedString -> [PackedString]

The linesPS function splits the input on line-breaks.

unlinesPS :: [PackedString] -> PackedString

The unlinesPS function concatenates the input list after interspersing newlines.

wordsPS :: PackedString -> [PackedString]

The wordsPS function is analogous to the words function.

unwordsPS :: [PackedString] -> PackedString

The unwordsPS function is analogous to the unwords function.

splitPS :: Char -> PackedString -> [PackedString]

The splitPS function splits the input string on each occurrence of the given Char.

splitWithPS :: (Char -> Bool) -> PackedString -> [PackedString]

The splitWithPS function takes a character predicate and splits the input string at each character which satisfies the predicate.

joinPS :: PackedString -> [PackedString] -> PackedString

The joinPS function takes a PackedString and a list of PackedStrings and concatenates the list after interspersing the first argument between each element of the list.