 | HaXml-1.13.2: Utilities for manipulating XML documents | Contents | Index |
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| Text.ParserCombinators.HuttonMeijerWallace |
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| Description |
| This library of monadic parser combinators is based on the ones
defined by Graham Hutton and Erik Meijer. It has been extended by
Malcolm Wallace to use an abstract token type (no longer just a
string) as input, and to incorporate a State Transformer monad, useful
for symbol tables, macros, and so on. Basic facilities for error
reporting have also been added, and later extended by Graham Klyne
to return the errors through an Either type, rather than just
calling error.
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| Synopsis |
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| newtype Parser s t e a = P (s -> [Either e t] -> ParseResult s t e a) | | | item :: Parser s t e t | | | eof :: Show p => Parser s (p, t) String () | | | papply :: Parser s t String a -> s -> [Either String t] -> [(a, s, [Either String t])] | | | papply' :: Parser s t e a -> s -> [Either e t] -> Either e [(a, s, [Either e t])] | | | (+++) :: Parser s t e a -> Parser s t e a -> Parser s t e a | | | tok :: Eq t => t -> Parser s (p, t) e t | | | nottok :: Eq t => [t] -> Parser s (p, t) e t | | | many :: Parser s t e a -> Parser s t e [a] | | | many1 :: Parser s t e a -> Parser s t e [a] | | | sepby :: Parser s t e a -> Parser s t e b -> Parser s t e [a] | | | sepby1 :: Parser s t e a -> Parser s t e b -> Parser s t e [a] | | | chainl :: Parser s t e a -> Parser s t e (a -> a -> a) -> a -> Parser s t e a | | | chainl1 :: Parser s t e a -> Parser s t e (a -> a -> a) -> Parser s t e a | | | chainr :: Parser s t e a -> Parser s t e (a -> a -> a) -> a -> Parser s t e a | | | chainr1 :: Parser s t e a -> Parser s t e (a -> a -> a) -> Parser s t e a | | | ops :: [(Parser s t e a, b)] -> Parser s t e b | | | bracket :: (Show p, Show t) => Parser s (p, t) e a -> Parser s (p, t) e b -> Parser s (p, t) e c -> Parser s (p, t) e b | | | toEOF :: Show p => Parser s (p, t) String a -> Parser s (p, t) String a | | | elserror :: (Show p, Show t) => Parser s (p, t) String a -> String -> Parser s (p, t) String a | | | stupd :: (s -> s) -> Parser s t e () | | | stquery :: (s -> a) -> Parser s t e a | | | stget :: Parser s t e s | | | reparse :: [Either e t] -> Parser s t e () |
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| The parser monad
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| newtype Parser s t e a |
| Constructors | | P (s -> [Either e t] -> ParseResult s t e a) | The parser type is parametrised on the types of the state s,
the input tokens t, error-type e, and the result value a.
The state and remaining input are threaded through the monad.
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|  Instances | |
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| Primitive parser combinators
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| item :: Parser s t e t |
| Deliver the first remaining token.
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| eof :: Show p => Parser s (p, t) String () |
| Fail if end of input is not reached
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| papply :: Parser s t String a -> s -> [Either String t] -> [(a, s, [Either String t])] |
| Apply the parser to some real input, given an initial state value.
If the parser fails, raise error to halt the program.
(This is the original exported behaviour - to allow the caller to
deal with the error differently, see papply'.)
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| papply' :: Parser s t e a -> s -> [Either e t] -> Either e [(a, s, [Either e t])] |
| Apply the parser to some real input, given an initial state value.
If the parser fails, return a diagnostic message to the caller.
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| Derived combinators
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| (+++) :: Parser s t e a -> Parser s t e a -> Parser s t e a |
| A choice between parsers. Keep only the first success.
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| tok :: Eq t => t -> Parser s (p, t) e t |
| Deliver the first token if it equals the argument.
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| nottok :: Eq t => [t] -> Parser s (p, t) e t |
| Deliver the first token if it does not equal the argument.
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| many :: Parser s t e a -> Parser s t e [a] |
| Deliver zero or more values of a.
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| many1 :: Parser s t e a -> Parser s t e [a] |
| Deliver one or more values of a.
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| sepby :: Parser s t e a -> Parser s t e b -> Parser s t e [a] |
| Deliver zero or more values of a separated by b's.
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| sepby1 :: Parser s t e a -> Parser s t e b -> Parser s t e [a] |
| Deliver one or more values of a separated by b's.
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| chainl :: Parser s t e a -> Parser s t e (a -> a -> a) -> a -> Parser s t e a |
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| chainl1 :: Parser s t e a -> Parser s t e (a -> a -> a) -> Parser s t e a |
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| chainr :: Parser s t e a -> Parser s t e (a -> a -> a) -> a -> Parser s t e a |
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| chainr1 :: Parser s t e a -> Parser s t e (a -> a -> a) -> Parser s t e a |
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| ops :: [(Parser s t e a, b)] -> Parser s t e b |
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| bracket :: (Show p, Show t) => Parser s (p, t) e a -> Parser s (p, t) e b -> Parser s (p, t) e c -> Parser s (p, t) e b |
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| toEOF :: Show p => Parser s (p, t) String a -> Parser s (p, t) String a |
| Accept a complete parse of the input only, no partial parses.
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| Error handling
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| elserror :: (Show p, Show t) => Parser s (p, t) String a -> String -> Parser s (p, t) String a |
| If the parser fails, generate an error message.
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| State handling
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| stupd :: (s -> s) -> Parser s t e () |
| Update the internal state.
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| stquery :: (s -> a) -> Parser s t e a |
| Query the internal state.
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| stget :: Parser s t e s |
| Deliver the entire internal state.
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| Re-parsing
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| reparse :: [Either e t] -> Parser s t e () |
| This is useful 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.
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| Produced by Haddock version 0.8 |