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§
source§impl<E> Err<E>
impl<E> Err<E>
Trait Implementations§
source§impl<E> Error for Err<E>where
E: Debug,
impl<E> Error for Err<E>where
E: Debug,
source§fn source(&self) -> Option<&(dyn Error + 'static)>
fn source(&self) -> Option<&(dyn Error + 'static)>
Returns the lower-level source of this error, if any. Read more
1.0.0 · source§fn description(&self) -> &str
fn description(&self) -> &str
👎Deprecated since 1.42.0: use the Display impl or to_string()
impl<E: Eq> Eq for Err<E>
impl<E> StructuralPartialEq for Err<E>
Auto Trait Implementations§
impl<E> Freeze for Err<E>where
E: Freeze,
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§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
🔬This is a nightly-only experimental API. (
clone_to_uninit
)