Text.LaTeX.Base.Parser

The LaTeX parser.

Use parseLaTeX to parse a Text containing LaTeX code. If the Text is in a file, you may want to use parseLaTeXFile. Use this module together with Text.LaTeX.Base.Syntax to perform analysis and transformations of LaTeX code. The parser (parseLaTeX) is related with the renderer (render) by the following property:

If t :: Text is a syntactically valid LaTeX block, then:

fmap render (parseLaTeX t) == Right t

This property says two things:

• Given a valid LaTeX input, parseLaTeX returns a LaTeX value.
• If the parsed value is again rendered, you get the initial input.

In other words, parseLaTeX is a partial function defined over the set of valid LaTeX files, and render is its left inverse.

The parser

parseLaTeX :: Text -> Either ParseError LaTeX

Parse a Text sequence as a LaTeX block. If it fails, it returns an error string.

parseLaTeXFile :: FilePath -> IO (Either ParseError LaTeX)

Read a file and parse it as LaTeX.

Parsing errors

data ParseError

The abstract data type ParseError represents parse errors. It provides the source position (SourcePos) of the error and a list of error messages (Message). A ParseError can be returned by the function parse. ParseError is an instance of the Show and Eq classes.

Instances

Eq ParseError

Defined in Text.Parsec.Error

Methods

(==) :: ParseError -> ParseError -> Bool

(/=) :: ParseError -> ParseError -> Bool

Show ParseError

Defined in Text.Parsec.Error

Methods

showsPrec :: Int -> ParseError -> ShowS

show :: ParseError -> String

showList :: [ParseError] -> ShowS

errorPos :: ParseError -> SourcePos

Extracts the source position from the parse error

errorMessages :: ParseError -> [Message]

Extracts the list of error messages from the parse error

Error messages

data Message

This abstract data type represents parse error messages. There are four kinds of messages:

 data Message = SysUnExpect String
              | UnExpect String
              | Expect String
              | Message String

The fine distinction between different kinds of parse errors allows the system to generate quite good error messages for the user. It also allows error messages that are formatted in different languages. Each kind of message is generated by different combinators:

• A SysUnExpect message is automatically generated by the satisfy combinator. The argument is the unexpected input.
• A UnExpect message is generated by the unexpected combinator. The argument describes the unexpected item.
• A Expect message is generated by the <?> combinator. The argument describes the expected item.
• A Message message is generated by the fail combinator. The argument is some general parser message.

Constructors

SysUnExpect !String

UnExpect !String

Expect !String

Message !String

Instances

Enum Message

Defined in Text.Parsec.Error

Methods

succ :: Message -> Message

pred :: Message -> Message

toEnum :: Int -> Message

fromEnum :: Message -> Int

enumFrom :: Message -> [Message]

enumFromThen :: Message -> Message -> [Message]

enumFromTo :: Message -> Message -> [Message]

enumFromThenTo :: Message -> Message -> Message -> [Message]

Eq Message

Defined in Text.Parsec.Error

Methods

(==) :: Message -> Message -> Bool

(/=) :: Message -> Message -> Bool

Ord Message

Defined in Text.Parsec.Error

Methods

compare :: Message -> Message -> Ordering

(<) :: Message -> Message -> Bool

(<=) :: Message -> Message -> Bool

(>) :: Message -> Message -> Bool

(>=) :: Message -> Message -> Bool

max :: Message -> Message -> Message

min :: Message -> Message -> Message

messageString :: Message -> String

Extract the message string from an error message

Source positions

data SourcePos

The abstract data type SourcePos represents source positions. It contains the name of the source (i.e. file name), a line number and a column number. SourcePos is an instance of the Show, Eq and Ord class.

Instances

Eq SourcePos

Defined in Text.Parsec.Pos

Methods

(==) :: SourcePos -> SourcePos -> Bool

(/=) :: SourcePos -> SourcePos -> Bool

Data SourcePos

Defined in Text.Parsec.Pos

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SourcePos -> c SourcePos

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c SourcePos

toConstr :: SourcePos -> Constr

dataTypeOf :: SourcePos -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c SourcePos)

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c SourcePos)

gmapT :: (forall b. Data b => b -> b) -> SourcePos -> SourcePos

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SourcePos -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SourcePos -> r

gmapQ :: (forall d. Data d => d -> u) -> SourcePos -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> SourcePos -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> SourcePos -> m SourcePos

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SourcePos -> m SourcePos

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SourcePos -> m SourcePos

Ord SourcePos

Defined in Text.Parsec.Pos

Methods

compare :: SourcePos -> SourcePos -> Ordering

(<) :: SourcePos -> SourcePos -> Bool

(<=) :: SourcePos -> SourcePos -> Bool

(>) :: SourcePos -> SourcePos -> Bool

(>=) :: SourcePos -> SourcePos -> Bool

max :: SourcePos -> SourcePos -> SourcePos

min :: SourcePos -> SourcePos -> SourcePos

Show SourcePos

Defined in Text.Parsec.Pos

Methods

showsPrec :: Int -> SourcePos -> ShowS

show :: SourcePos -> String

showList :: [SourcePos] -> ShowS

sourceLine :: SourcePos -> Line

Extracts the line number from a source position.

sourceColumn :: SourcePos -> Column

Extracts the column number from a source position.

sourceName :: SourcePos -> SourceName

Extracts the name of the source from a source position.

Configuring your parser

data ParserConf

Configuration for the LaTeX parser.

Constructors

ParserConf

Fields

• verbatimEnvironments :: [String]

  This is the list of names of the environments such that their content will be parsed verbatim.

defaultParserConf :: ParserConf

Default parser configuration, used by parseLaTeX and parseLaTeXFile.

Defaults:

verbatimEnvironments = ["verbatim"]

parseLaTeXWith :: ParserConf -> Text -> Either ParseError LaTeX

parseLaTeXFileWith :: ParserConf -> FilePath -> IO (Either ParseError LaTeX)

Parser combinators

type Parser = Parsec Text ParserConf

Parser with Text input and ParserConf environment.

latexParser :: Parser LaTeX

The LaTeX parser.

latexBlockParser :: Parser LaTeX

Parser of a single LaTeX constructor, no appending blocks.