Module winnow::error

Error management

Errors are designed with multiple needs in mind:

• Accumulate more context as the error goes up the parser chain
• Distinguish between recoverable errors, unrecoverable errors, and more data is needed
• Have a very low overhead, as errors are often discarded by the calling parser (examples: many0, alt)
• Can be modified according to the user’s needs, because some languages need a lot more information
• Help thread-through the stream

To abstract these needs away from the user, generally winnow parsers use the IResult alias, rather than Result. finish is provided for top-level parsers to integrate with your application’s error reporting.

Error types include:

• ()
• Error
• VerboseError
• [Custom errors][crate::_topic::error]

Structs

Error

Default error type, only contains the error’ location and kind

VerboseError

Accumulates error information while backtracking

Enums

ErrMode

The Err enum indicates the parser was not successful

ErrorKind

Provide some minor debug context for errors

Needed

Contains information on needed data if a parser returned Incomplete

VerboseErrorKind

Error context for VerboseError

Traits

ContextError

Used by Parser::context to add custom data to error while backtracking

ErrorConvert

Equivalent of From implementation to avoid orphan rules in bits parsers

FinishIResultDeprecated

Extension trait to convert a parser’s IResult to a more manageable type

FromExternalError

Create a new error with an external error, from std::str::FromStr

ParseError

The basic Parser trait for errors

Functions

convert_error

Transforms a VerboseError into a trace with input position information

Type Definitions

IResult

Holds the result of Parser