Portability | portable |
---|---|
Stability | provisional |
Maintainer | derek.a.elkins@gmail.com |
Parse errors
- data Message
- messageString :: Message -> String
- 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 theText.Parsec.Combinator.satisfy
combinator. The argument is the unexpected input. - A
UnExpect
message is generated by theText.Parsec.Prim.unexpected
combinator. The argument describes the unexpected item. - A
Expect
message is generated by theText.Parsec.Prim.<?>
combinator. The argument describes the expected item. - A
Message
message is generated by thefail
combinator. The argument is some general parser message.
messageString :: Message -> StringSource
Extract the message string from an error message
data ParseError Source
errorPos :: ParseError -> SourcePosSource
Extracts the source position from the parse error
errorMessages :: ParseError -> [Message]Source
Extracts the list of error messages from the parse error
newErrorMessage :: Message -> SourcePos -> ParseErrorSource
addErrorMessage :: Message -> ParseError -> ParseErrorSource
setErrorPos :: SourcePos -> ParseError -> ParseErrorSource
setErrorMessage :: Message -> ParseError -> ParseErrorSource
mergeError :: ParseError -> ParseError -> ParseErrorSource