Struct failure::Error
[−]
[src]
pub struct Error { /* fields omitted */ }The Error type, which can contain any failure.
Functions which accumulate many kinds of errors should return this type.
All failures can be converted into it, so functions which catch those
errors can be tried with ? inside of a function that returns this kind
of Error.
In addition to implementing Debug and Display, this type carries Backtrace information, and can be downcast into the failure that underlies it for more detailed inspection.
Methods
impl Error[src]
fn cause(&self) -> &Fail[src]
Returns a reference to the underlying cause of this Error. Unlike the
method on Fail, this does not return an Option. The Error type
always has an underlying failure.
fn backtrace(&self) -> &Backtrace[src]
Get a reference to the Backtrace for this Error.
If the failure this wrapped carried a backtrace, that backtrace will be returned. Otherwise, the backtrace will have been constructed at the point that failure was cast into the Error type.
fn context<D: Display + Send + Sync + 'static>(self, context: D) -> Context<D>[src]
Provide context for this Error.
This can provide additional information about this error, appropriate to the semantics of the current layer. That is, if you have a lower level error, such as an IO error, you can provide additional context about what that error means in the context of your function. This gives users of this function more information about what has gone wrong.
This takes any type that implements Display, as well as Send/Sync/'static. In practice, this means it can take a String or a string literal, or a failure, or some other custom context carrying type.
fn compat(self) -> Compat<Error>[src]
Wrap Error in a compatibility type.
This type implements the Error trait from std::error. If you need
to pass failure's Error to an interface that takes any Error, you
can use this method to get a compatible type.
fn downcast<T: Fail>(self) -> Result<T, Error>[src]
Attempt to downcast this Error to a particular Fail type.
This downcasts by value, returning an owned T if the underlying
failure is of the type T. For this reason it returns a Result - in
the case that the underlying error is of a different type, the
original Error is returned.
fn root_cause(&self) -> &Fail[src]
Returns the "root cause" of this error - the last value in the
cause change which does not return an underlying cause.
fn downcast_ref<T: Fail>(&self) -> Option<&T>[src]
Attempt to downcast this Error to a particular Fail type by
reference.
If the underlying error is not of type T, this will return None.
fn downcast_mut<T: Fail>(&mut self) -> Option<&mut T>[src]
Attempt to downcast this Error to a particular Fail type by
mutable reference.
If the underlying error is not of type T, this will return None.
Trait Implementations
impl<F: Fail> From<F> for Error[src]
impl Display for Error[src]
fn fmt(&self, f: &mut Formatter) -> Result[src]
Formats the value using the given formatter. Read more