pub enum Err<E> {
Incomplete(Needed),
Error(E),
Failure(E),
}
Expand description
The Err
enum indicates the parser was not successful
It has three cases:
Incomplete
indicates that more data is needed to decide. TheNeeded
enum can contain how many additional bytes are necessary. If you are sure your parser is working on full data, you can wrap your parser with thecomplete
combinator to transform that case inError
Error
means some parser did not succeed, but another one might (as an example, when testing different branches of analt
combinator)Failure
indicates an unrecoverable error. As an example, if you recognize a prefix to decide on the next parser to apply, and that parser fails, you know there’s no need to try other parsers, you were already in the right branch, so the data is invalid
Variants
Incomplete(Needed)
There was not enough data
Error(E)
The parser had an error (recoverable)
Failure(E)
The parser had an unrecoverable error: we got to the right branch and we know other branches won’t work, so backtrack as fast as possible
Implementations
sourceimpl<E> Err<E>
impl<E> Err<E>
Trait Implementations
sourceimpl<E> Error for Err<E> where
E: Debug,
impl<E> Error for Err<E> where
E: Debug,
sourcefn source(&self) -> Option<&(dyn Error + 'static)>
fn source(&self) -> Option<&(dyn Error + 'static)>
The lower-level source of this error, if any. Read more
sourcefn backtrace(&self) -> Option<&Backtrace>
fn backtrace(&self) -> Option<&Backtrace>
🔬 This is a nightly-only experimental API. (
backtrace
)Returns a stack backtrace, if available, of where this error occurred. Read more
1.0.0 · sourcefn description(&self) -> &str
fn description(&self) -> &str
👎 Deprecated since 1.42.0:
use the Display impl or to_string()
impl<E> Eq for Err<E> where
E: Eq,
impl<E> StructuralPartialEq for Err<E>
Auto Trait Implementations
impl<E> RefUnwindSafe for Err<E> where
E: RefUnwindSafe,
impl<E> Send for Err<E> where
E: Send,
impl<E> Sync for Err<E> where
E: Sync,
impl<E> Unpin for Err<E> where
E: Unpin,
impl<E> UnwindSafe for Err<E> where
E: UnwindSafe,
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more