Struct Error 

pub struct Error {
    pub kind: ErrorKind,
    /* private fields */
}

Error type for parsing.

Fields

kind: ErrorKind

Kind of the error.

Implementations

impl Error

pub const fn no_error() -> Error

Create a ErrorKind::NoError error.

pub fn upgrade<T>(&mut self, r: Result<T, Error>) -> Result<T, Error>

Upgrade an error to one with greater pos value.

pub fn set_pos(&mut self, pos: impl TokenCount)

Set the position of the error.

Sometimes the position of the error is not known at the time of creation. This allows to adjust it later.

pub const fn pos(&self) -> usize

Get the position of the error.

pub fn unexpected_token<T>( at: Option<TokenTree>, after: &TokenIter, ) -> Result<T, Error>

Create a Result<T>::Err(Error{ kind: ErrorKind::UnexpectedToken }) error at a token iter position. Takes the failed token (if available) and a reference to the TokenIter past the error.

Note on position tracking

The pos field is set to after.counter(), which represents the number of tokens that were consumed up to and including the failed token (if any):

• If at is Some(token): The token was consumed by next() which incremented the counter, so pos reflects the position AFTER consuming the failed token.
• If at is None: The iterator was exhausted, so pos reflects how many tokens were successfully consumed before running out.

pub fn unexpected_end<T>() -> Result<T, Error>

Create a Result<T>::Err(Error{ kind: ErrorKind::UnexpectedToken }) error without a token iter.

pub fn out_of_range<const LIM: usize, T>( have: usize, at: Option<TokenTree>, after: &TokenIter, ) -> Result<T, Error>

Create a Result<T>::Err(Error{ kind: ErrorKind::OutOfRange }) error at a token iter position. Takes the failed token (if available) and a reference to the TokenIter past the error.

pub fn other<T>( at: Option<TokenTree>, after: &TokenIter, reason: String, ) -> Result<T, Error>

Create a Result<T>::Err(Error{ kind: ErrorKind::Other }) error. Takes the failed token (if available), a reference to the TokenIter past the error and a String describing the error.

pub fn infinite_loop<T>( at: Option<TokenTree>, after: &TokenIter, ) -> Result<T, Error>

Create a Result<T>::Err(Error{ kind: ErrorKind::InfiniteLoop }) error. Used when a repeating (conatianer) parser detects that the inner parser succeeded without consuming any tokens, which would lead to an infinite loop.

pub fn dynamic<T>( at: Option<TokenTree>, after: &TokenIter, error: impl Error + Send + Sync + 'static, ) -> Result<T, Error>

Create a Result<T>::Err(Error{ kind: ErrorKind::Dynamic }) error. Takes the failed token (if available), a reference to the TokenIter past the error and a boxed error.

pub fn expected_type_name(&self) -> &'static str

Returns the refined type name of the parser that failed.

pub const fn expected_original_type_name(&self) -> &'static str

Returns the original/fundamental type name of the parser that failed.

pub fn failed_at(&self) -> Option<TokenTree>

Returns a Option<TokenTree> where the error happend.

pub fn tokens_after(&self) -> TokenIter

Returns a iterator to the tokens after the error

Creates a new TokenIter from the stored token stream position

Trait Implementations

impl Clone for Error

fn clone(&self) -> Error

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Error

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

Formats the value using the given formatter.

impl Display for Error

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

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.