tokio_executor/
error.rs

1use std::error::Error;
2use std::fmt;
3
4/// Errors returned by `Executor::spawn`.
5///
6/// Spawn errors should represent relatively rare scenarios. Currently, the two
7/// scenarios represented by `SpawnError` are:
8///
9/// * An executor being at capacity or full. As such, the executor is not able
10///   to accept a new future. This error state is expected to be transient.
11/// * An executor has been shutdown and can no longer accept new futures. This
12///   error state is expected to be permanent.
13#[derive(Debug)]
14pub struct SpawnError {
15    is_shutdown: bool,
16}
17
18impl SpawnError {
19    /// Return a new `SpawnError` reflecting a shutdown executor failure.
20    pub fn shutdown() -> Self {
21        SpawnError { is_shutdown: true }
22    }
23
24    /// Return a new `SpawnError` reflecting an executor at capacity failure.
25    pub fn at_capacity() -> Self {
26        SpawnError { is_shutdown: false }
27    }
28
29    /// Returns `true` if the error reflects a shutdown executor failure.
30    pub fn is_shutdown(&self) -> bool {
31        self.is_shutdown
32    }
33
34    /// Returns `true` if the error reflects an executor at capacity failure.
35    pub fn is_at_capacity(&self) -> bool {
36        !self.is_shutdown
37    }
38}
39
40impl fmt::Display for SpawnError {
41    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
42        write!(fmt, "{}", self.description())
43    }
44}
45
46impl Error for SpawnError {
47    fn description(&self) -> &str {
48        "attempted to spawn task while the executor is at capacity or shut down"
49    }
50}
tokio_executor/error.rs

tokio_executor/
error.rs
