Struct ContextError

pub struct ContextError<C = StrContext> { /* private fields */ }

Accumulate context while backtracking errors

See the [tutorial][crate::_tutorial::chapter_7#error-adaptation-and-rendering] for an example of how to adapt this to an application error with custom rendering.

Implementations

impl<C> ContextError<C>

pub fn new() -> Self

Create an empty error

pub fn push(&mut self, context: C)

Add more context

pub fn extend<I: IntoIterator<Item = C>>(&mut self, context: I)

Add more context

pub fn context(&self) -> impl Iterator<Item = &C>

Available on crate feature alloc only.

Access context from Parser::context

pub fn cause(&self) -> Option<&(dyn Error + Send + Sync + 'static)>

Available on crate feature std only.

Originating std::error::Error

Trait Implementations

impl<C, I: Stream> AddContext<I, C> for ContextError<C>

fn add_context( self, _input: &I, _token_start: &<I as Stream>::Checkpoint, context: C, ) -> Self

Append to an existing error custom data

impl<C: Clone> Clone for ContextError<C>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<C: Debug> Debug for ContextError<C>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<C> Default for ContextError<C>

fn default() -> Self

Returns the “default value” for a type.

impl Display for ContextError<StrContext>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<C> ErrorConvert<ContextError<C>> for ContextError<C>

fn convert(self) -> ContextError<C>

Transform to another error type

impl<C, I, E: Error + Send + Sync + 'static> FromExternalError<I, E> for ContextError<C>

Available on crate feature std only.

fn from_external_error(_input: &I, e: E) -> Self

Like ParserError::from_input but also include an external error.

impl<I: Stream, C> ParserError<I> for ContextError<C>

type Inner = ContextError<C>

Generally, Self

fn from_input(_input: &I) -> Self

Creates an error from the input position

fn into_inner(self) -> Result<Self::Inner, Self>

Unwrap the mode, returning the underlying error, if present

fn assert(input: &I, _message: &'static str) -> Self

where I: Debug,

Process a parser assertion

fn incomplete(input: &I, _needed: Needed) -> Self

There was not enough data to determine the appropriate action

fn append(self, _input: &I, _token_start: &<I as Stream>::Checkpoint) -> Self

Like ParserError::from_input but merges it with the existing error.

fn or(self, other: Self) -> Self

Combines errors from two different parse branches.

fn is_backtrack(&self) -> bool

Is backtracking and trying new parse branches allowed?

fn is_incomplete(&self) -> bool

Is more data Needed

fn needed(&self) -> Option<Needed>

Extract the Needed data, if present

impl<C: PartialEq> PartialEq for ContextError<C>

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 40 bytes