Data.MIME.Charset

MIME character sets.

Recognised charsets:

• us-ascii / iso646-us

• utf-8

• iso-8859-1

See also the purebred-icu plugin, which adds support for many character sets.

Documentation

class HasCharset a where

Minimal complete definition

charsetName, charsetData, charsetDecoded, charsetEncode

Associated Types

type Decoded a

Methods

charsetName :: Getter a (Maybe CharsetName)

Get the declared (or default) character set name. There is no guarantee that it corresponds to a registered or supported charset.

charsetData :: Getter a ByteString

Return the encoded data in the structure

charsetDecoded :: AsCharsetError e => CharsetLookup -> forall p f. (Profunctor p, Contravariant f) => Optic' p f a (Either e (Decoded a))

Structure with the encoded data replaced with Text

charsetDecoded' :: CharsetLookup -> forall p f. (Profunctor p, Contravariant f) => Optic' p f a (Either CharsetError (Decoded a))

Structure with the encoded data replaced with Text (monomorphic error type)

charsetEncode :: Decoded a -> a

Encode the data

Instances

HasCharset ByteEntity

RFC 6657 specifies that each subtype of the text media type can define its own default value for the charset parameter, including the absense of any default. It can also specify that the charset information is transported inside the payload (such as in text/xml. Behaviour for common media types includes:

text/plain

Default: us-ascii (RFC 6657)

text/csv

Default: utf-8 (RFC 7111)

text/markdown

No default; charset parameter is REQUIRED (RFC 7763)

text/enriched

Default: us-ascii (RFC 1896)

text/rtf

Decoded as us-ascii. Serialised RTF must be 7-bit ASCII, with the character set declared in the payload. Decoding RTF is outside the scope of this library. See https://www.iana.org/assignments/media-types/text/rtf.

Defined in Data.MIME

Associated Types

type Decoded ByteEntity

Methods

charsetName :: Getter ByteEntity (Maybe CharsetName)

charsetData :: Getter ByteEntity ByteString

charsetDecoded :: AsCharsetError e => CharsetLookup -> forall (p :: Type -> Type -> Type) (f :: Type -> Type). (Profunctor p, Contravariant f) => Optic' p f ByteEntity (Either e (Decoded ByteEntity))

charsetDecoded' :: CharsetLookup -> forall (p :: Type -> Type -> Type) (f :: Type -> Type). (Profunctor p, Contravariant f) => Optic' p f ByteEntity (Either CharsetError (Decoded ByteEntity))

charsetEncode :: Decoded ByteEntity -> ByteEntity

HasCharset EncodedParameterValue

The default charset us-ascii is implied by the abstract of RFC 2231 which states: /This memo defines … a means to specify parameter values in character sets other than US-ASCII/.

When encoding, 'utf-8' is always used, but if the whole string contains only ASCII characters then the charset declaration is omitted (so that it can be encoded as a non-extended parameter).

Defined in Data.MIME.Parameter

Associated Types

type Decoded EncodedParameterValue

Methods

charsetName :: Getter EncodedParameterValue (Maybe CharsetName)

charsetData :: Getter EncodedParameterValue ByteString

charsetDecoded :: AsCharsetError e => CharsetLookup -> forall (p :: Type -> Type -> Type) (f :: Type -> Type). (Profunctor p, Contravariant f) => Optic' p f EncodedParameterValue (Either e (Decoded EncodedParameterValue))

charsetDecoded' :: CharsetLookup -> forall (p :: Type -> Type -> Type) (f :: Type -> Type). (Profunctor p, Contravariant f) => Optic' p f EncodedParameterValue (Either CharsetError (Decoded EncodedParameterValue))

charsetEncode :: Decoded EncodedParameterValue -> EncodedParameterValue

type CharsetName = CI ByteString

charsetText :: (HasCharset a, AsCharsetError e, Profunctor p, Contravariant f) => CharsetLookup -> Optic' p f a (Either e Text)

Decode the object according to the declared charset.

charsetText' :: (HasCharset a, Profunctor p, Contravariant f) => CharsetLookup -> Optic' p f a (Either CharsetError Text)

Monomorphic in error type

data CharsetError

Constructors

CharsetUnspecified

CharsetUnsupported CharsetName

CharsetDecodeError CharsetName

Instances

Show CharsetError

Defined in Data.MIME.Charset

Methods

showsPrec :: Int -> CharsetError -> ShowS

show :: CharsetError -> String

showList :: [CharsetError] -> ShowS

AsCharsetError CharsetError

Defined in Data.MIME.Charset

Methods

_CharsetError :: Prism' CharsetError CharsetError

_CharsetUnspecified :: Prism' CharsetError ()

_CharsetUnsupported :: Prism' CharsetError CharsetName

_CharsetDecodeError :: Prism' CharsetError CharsetName

class AsCharsetError s where

Minimal complete definition

_CharsetError

Methods

_CharsetError :: Prism' s CharsetError

_CharsetUnspecified :: Prism' s ()

_CharsetUnsupported :: Prism' s CharsetName

_CharsetDecodeError :: Prism' s CharsetName

Instances

AsCharsetError CharsetError

Defined in Data.MIME.Charset

Methods

_CharsetError :: Prism' CharsetError CharsetError

_CharsetUnspecified :: Prism' CharsetError ()

_CharsetUnsupported :: Prism' CharsetError CharsetName

_CharsetDecodeError :: Prism' CharsetError CharsetName

AsCharsetError EncodingError

Defined in Data.MIME.Error

Methods

_CharsetError :: Prism' EncodingError CharsetError

_CharsetUnspecified :: Prism' EncodingError ()

_CharsetUnsupported :: Prism' EncodingError CharsetName

_CharsetDecodeError :: Prism' EncodingError CharsetName

charsetPrism :: forall a. HasCharset a => CharsetLookup -> Prism' a (Decoded a)

Prism for charset decoded/encoded data. Information about decoding failures is discarded.

type CharsetLookup = CI ByteString -> Maybe Charset

defaultCharsets :: CharsetLookup

Supports US-ASCII, UTF-8 and ISO-8859-1, UTF-16[BE|LE] and UTF-32[BE|LE]. The purebred-icu package provides support for more charsets.

decodeLenient :: ByteString -> Text

Decode as UTF-8, replacing invalid sequences with placeholders.