Safe Haskell	Safe-Inferred
Language	Haskell98

Text.XML.HaXml.Xtract.Lex

Description

This is another hand-written lexer, this time for the Xtract command-language. The entry point is lexXtract. You don't normally need to use this module directly - the lexer is called automatically by the parser. (We only expose this interface for debugging purposes.)

The Xtract command language is very like the XPath specification.

Synopsis

lexXtract :: (String -> String) -> String -> [Token]
data Posn = Pn Int
data TokenT
- = Symbol String
- | TokString String
- | TokNum Integer
type Token = Either String (Posn, TokenT)

Documentation

lexXtract :: (String -> String) -> String -> [Token] Source #

First argument is a transformer for pattern strings, e.g. map toLower, but only applying to parts of the pattern not in quotation marks. (Needed to canonicalise HTML where tags are case-insensitive, but attribute values are case sensitive.)

data Posn Source #

Constructors

Pn Int

Instances

Instances details

Eq Posn Source #
Instance details Defined in Text.XML.HaXml.Xtract.Lex Methods (==) :: Posn -> Posn -> Bool (/=) :: Posn -> Posn -> Bool
Show Posn Source #
Instance details Defined in Text.XML.HaXml.Xtract.Lex Methods showsPrec :: Int -> Posn -> ShowS show :: Posn -> String showList :: [Posn] -> ShowS

data TokenT Source #

Constructors

Symbol String
TokString String
TokNum Integer

Instances

Instances details

Eq TokenT Source #
Instance details Defined in Text.XML.HaXml.Xtract.Lex Methods (==) :: TokenT -> TokenT -> Bool (/=) :: TokenT -> TokenT -> Bool
Show TokenT Source #
Instance details Defined in Text.XML.HaXml.Xtract.Lex Methods showsPrec :: Int -> TokenT -> ShowS show :: TokenT -> String showList :: [TokenT] -> ShowS

type Token = Either String (Posn, TokenT) Source #