polyparse-1.3: A variety of alternative parser combinator libraries.




The Parser datatype

newtype Parser s t a Source

This Parser datatype is a fairly generic parsing monad with error reporting. It can be used for arbitrary token types, not just String input. (If you require a running state, use module PolyState instead)


P (s -> [t] -> Result [t] s a) 


Monad (Parser s t) 
Functor (Parser s t) 
PolyParse (Parser s t) 

data Result z s a Source

A return type like Either, that distinguishes not only between right and wrong answers, but also has gradations of wrongness. This should only be used for writing very primitive parsers - really it is an internal detail of the library.


Success z s a 
Failure z s String 
Committed (Result z s a) 


Functor (Result z s) 

runParser :: Parser s t a -> s -> [t] -> (a, s, [t])Source

Apply a parser to an input token sequence.

basic parsers

satisfy :: (t -> Bool) -> Parser s t tSource

manyFinally :: Parser s t a -> Parser s t z -> Parser s t [a]Source


stUpdate :: (s -> s) -> Parser s t ()Source

Update the internal state.

stQuery :: (s -> a) -> Parser s t aSource

Query the internal state.

stGet :: Parser s t sSource

Deliver the entire internal state.


reparse :: [t] -> Parser s t ()Source

Push some tokens back onto the front of the input stream and reparse. This is useful e.g. for recursively expanding macros. When the user-parser recognises a macro use, it can lookup the macro expansion from the parse state, lex it, and then stuff the lexed expansion back down into the parser.

Re-export all more general combinators