utf8-string-1: Support for reading and writing UTF8 Strings

Copyright(c) Iavor S. Diatchki 2009
LicenseBSD3-style (see LICENSE)
Maintaineremertens@galois.com
Stabilityexperimental
Portabilityportable This module provides fast, validated encoding and decoding functions between 'ByteString's and 'String's. It does not exactly match the output of the Codec.Binary.UTF8.String output for invalid encodings as the number of replacement characters is sometimes longer.
Safe HaskellTrustworthy
LanguageHaskell98

Data.ByteString.UTF8

Description

 

Synopsis

Documentation

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.

decode :: ByteString -> Maybe (Char, Int) Source

Try to extract a character from a byte string. Returns Nothing if there are no more bytes in the byte string. Otherwise, it returns a decoded character and the number of bytes used in its representation. Errors are replaced by character '\0xFFFD'.

replacement_char :: Char Source

This character is used to mark errors in a UTF8 encoded string.

uncons :: ByteString -> Maybe (Char, ByteString) Source

Get the first character of a byte string, if any. Malformed characters are replaced by '\0xFFFD'.

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

Split after a given number of characters. Negative values are treated as if they are 0.

take :: Int -> ByteString -> ByteString Source

take n s returns the first n characters of s. If s has less than n characters, then we return the whole of s.

drop :: Int -> ByteString -> ByteString Source

drop n s returns the s without its first n characters. If s has less than n characters, then we return an empty string.

span :: (Char -> Bool) -> ByteString -> (ByteString, ByteString) Source

Split a string into two parts: the first is the longest prefix that contains only characters that satisfy the predicate; the second part is the rest of the string. Invalid characters are passed as '\0xFFFD' to the predicate.

break :: (Char -> Bool) -> ByteString -> (ByteString, ByteString) Source

Split a string into two parts: the first is the longest prefix that contains only characters that do not satisfy the predicate; the second part is the rest of the string. Invalid characters are passed as '\0xFFFD' to the predicate.

fromString :: String -> ByteString Source

Converts a Haskell string into a UTF8 encoded bytestring.

toString :: ByteString -> String Source

Convert a UTF8 encoded bytestring into a Haskell string. Invalid characters are replaced with '\xFFFD'.

foldl :: (a -> Char -> a) -> a -> ByteString -> a Source

Traverse a bytestring (left biased). This function is strict in the accumulator.

foldr :: (Char -> a -> a) -> a -> ByteString -> a Source

Traverse a bytestring (right biased).

length :: ByteString -> Int Source

Counts the number of characters encoded in the bytestring. Note that this includes replacement characters.

lines :: ByteString -> [ByteString] Source

Split a string into a list of lines. Lines are terminated by '\n' or the end of the string. Empty lines may not be terminated by the end of the string. See also 'lines\''.

lines' :: ByteString -> [ByteString] Source

Split a string into a list of lines. Lines are terminated by '\n' or the end of the string. Empty lines may not be terminated by the end of the string. This function preserves the terminators. See also lines.