Text.XML.HaXml.Xtract.Lex

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.

Documentation

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

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

Constructors

Pn Int

Instances

Eq Posn

Show Posn

data TokenT

Constructors

Symbol String

TokString String

TokNum Integer

Instances

Eq TokenT

Show TokenT

type Token = Either String (Posn, TokenT)