Copyright | (c) Paolo Martini 2007 |
---|---|
License | BSD-style (see the LICENSE file) |
Maintainer | derek.a.elkins@gmail.com |
Stability | provisional |
Portability | portable |
Safe Haskell | Safe |
Language | Haskell2010 |
Text.ParserCombinators.Parsec.Error
Description
Parsec compatibility module
Synopsis
- data Message
- messageString :: Message -> String
- messageCompare :: Message -> Message -> Ordering
- messageEq :: Message -> Message -> Bool
- data ParseError
- errorPos :: ParseError -> SourcePos
- errorMessages :: ParseError -> [Message]
- errorIsUnknown :: ParseError -> Bool
- showErrorMessages :: String -> String -> String -> String -> String -> [Message] -> String
- newErrorMessage :: Message -> SourcePos -> ParseError
- newErrorUnknown :: SourcePos -> ParseError
- addErrorMessage :: Message -> ParseError -> ParseError
- setErrorPos :: SourcePos -> ParseError -> ParseError
- setErrorMessage :: Message -> ParseError -> ParseError
- mergeError :: ParseError -> ParseError -> ParseError
Documentation
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 thesatisfy
combinator. The argument is the unexpected input. - A
UnExpect
message is generated by theunexpected
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 thefail
combinator. The argument is some general parser message.
Instances
Enum Message Source # | |
Methods succ :: Message -> Message Source # pred :: Message -> Message Source # toEnum :: Int -> Message Source # fromEnum :: Message -> Int Source # enumFrom :: Message -> [Message] Source # enumFromThen :: Message -> Message -> [Message] Source # enumFromTo :: Message -> Message -> [Message] Source # enumFromThenTo :: Message -> Message -> Message -> [Message] Source # | |
Eq Message Source # | |
Ord Message Source # | |
messageString :: Message -> String Source #
Extract the message string from an error message
data ParseError Source #
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 Source # | |
Show ParseError Source # | |
errorPos :: ParseError -> SourcePos Source #
Extracts the source position from the parse error
errorMessages :: ParseError -> [Message] Source #
Extracts the list of error messages from the parse error
errorIsUnknown :: ParseError -> Bool Source #
newErrorMessage :: Message -> SourcePos -> ParseError Source #
addErrorMessage :: Message -> ParseError -> ParseError Source #
setErrorPos :: SourcePos -> ParseError -> ParseError Source #
setErrorMessage :: Message -> ParseError -> ParseError Source #
mergeError :: ParseError -> ParseError -> ParseError Source #