Struct rocket::Error[][src]

pub struct Error { /* fields omitted */ }
Expand description

An error that occurs during launch.

An Error is returned by launch() when launching an application fails or, more rarely, when the runtime fails after lauching.

Panics

A value of this type panics if it is dropped without first being inspected. An inspection occurs when any method is called. For instance, if println!("Error: {}", e) is called, where e: Error, the Display::fmt method being called by println! results in e being marked as inspected; a subsequent drop of the value will not result in a panic. The following snippet illustrates this:

if let Err(error) = rocket::build().launch().await {
    // This println "inspects" the error.
    println!("Launch failed! Error: {}", error);

    // This call to drop (explicit here for demonstration) will do nothing.
    drop(error);
}

When a value of this type panics, the corresponding error message is pretty printed to the console. The following illustrates this:

let error = rocket::build().launch().await;

// This call to drop (explicit here for demonstration) will result in
// `error` being pretty-printed to the console along with a `panic!`.
drop(error);

Usage

An Error value should usually be allowed to drop without inspection. There are at least two exceptions:

  1. If you are writing a library or high-level application on-top of Rocket, you likely want to inspect the value before it drops to avoid a Rocket-specific panic!. This typically means simply printing the value.

  2. You want to display your own error messages.

Implementations

impl Error[src]

pub fn kind(&self) -> &ErrorKind[src]

Retrieve the kind of the launch error.

Example

use rocket::error::ErrorKind;

if let Err(error) = rocket::build().launch().await {
    match error.kind() {
        ErrorKind::Io(e) => println!("found an i/o launch error: {}", e),
        e => println!("something else happened: {}", e)
    }
}

Trait Implementations

impl Debug for Error[src]

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

Formats the value using the given formatter. Read more

impl Display for Error[src]

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

Formats the value using the given formatter. Read more

impl Drop for Error[src]

fn drop(&mut self)[src]

Executes the destructor for this type. Read more

impl Error for Error[src]

fn source(&self) -> Option<&(dyn Error + 'static)>1.30.0[src]

The lower-level source of this error, if any. Read more

fn backtrace(&self) -> Option<&Backtrace>[src]

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

Returns a stack backtrace, if available, of where this error occurred. Read more

fn description(&self) -> &str1.0.0[src]

👎 Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>1.0.0[src]

👎 Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

impl From<ErrorKind> for Error[src]

fn from(kind: ErrorKind) -> Self[src]

Performs the conversion.

Auto Trait Implementations

impl !RefUnwindSafe for Error

impl Send for Error

impl Sync for Error

impl Unpin for Error

impl !UnwindSafe for Error

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized
[src]

pub fn type_id(&self) -> TypeId[src]

Gets the TypeId of self. Read more

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

pub fn borrow(&self) -> &T[src]

Immutably borrows from an owned value. Read more

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

pub fn borrow_mut(&mut self) -> &mut T[src]

Mutably borrows from an owned value. Read more

impl<T> From<T> for T[src]

pub fn from(t: T) -> T[src]

Performs the conversion.

impl<T> Instrument for T[src]

fn instrument(self, span: Span) -> Instrumented<Self>[src]

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

fn in_current_span(self) -> Instrumented<Self>[src]

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

pub fn into(self) -> U[src]

Performs the conversion.

impl<T> IntoCollection<T> for T

pub fn into_collection<A>(self) -> SmallVec<A> where
    A: Array<Item = T>, 

Converts self into a collection.

pub fn mapped<U, F, A>(self, f: F) -> SmallVec<A> where
    F: FnMut(T) -> U,
    A: Array<Item = U>, 

impl<T> Same<T> for T

type Output = T

Should always be Self

impl<T> ToString for T where
    T: Display + ?Sized
[src]

pub default fn to_string(&self) -> String[src]

Converts the given value to a String. Read more

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]

Performs the conversion.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>[src]

Performs the conversion.

impl<V, T> VZip<V> for T where
    V: MultiLane<T>, 

pub fn vzip(self) -> V