Enum BuildError 

#[non_exhaustive]
pub enum BuildError {
    #[non_exhaustive]
    ResourceLimitReached {
        resource: &'static str,
        limit: usize,
    },
    #[non_exhaustive]
    CapacityTooLarge {
        field: &'static str,
        value: usize,
        max: usize,
    },
    #[non_exhaustive]
    ThreadStartFailed {
        component: &'static str,
        worker: usize,
        kind: ErrorKind,
        raw_os_error: Option<i32>,
    },
}

Failure to build a stopped Supervisor.

SupervisorBuilder::try_build returns this type while validating capacities, reserving subscriber ownership, and starting required cleanup workers. No Supervisor is returned on failure.

This enum and its data-carrying variants are non-exhaustive; keep a fallback arm and use .. when matching fields.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

#[non_exhaustive]

ResourceLimitReached

The supervisor cannot reserve every required user-owned lifetime.

Fields

Non-exhaustive enum variants could have additional fields added in future. Therefore, non-exhaustive enum variants cannot be constructed in external crates and cannot be matched against.

resource: &'static str

Stable resource name suitable for diagnostics.

limit: usize

Reported supervisor-local limit.

#[non_exhaustive]

CapacityTooLarge

A bounded async capacity exceeds Tokio’s structural limit.

Fields

Non-exhaustive enum variants could have additional fields added in future. Therefore, non-exhaustive enum variants cannot be constructed in external crates and cannot be matched against.

field: &'static str

Stable configuration field name.

value: usize

Rejected value.

max: usize

Largest value accepted by the underlying primitive.

#[non_exhaustive]

ThreadStartFailed

A required build-time cleanup worker could not start.

Subscriber metadata callbacks have not run when this error is returned.

Fields

Non-exhaustive enum variants could have additional fields added in future. Therefore, non-exhaustive enum variants cannot be constructed in external crates and cannot be matched against.

component: &'static str

Stable build component name suitable for diagnostics.

worker: usize

Zero-based position in the worker startup batch.

kind: ErrorKind

Portable I/O error category.

raw_os_error: Option<i32>

Platform-specific OS error code, when one was available.

Implementations

impl BuildError

pub fn as_label(&self) -> &'static str

Returns the stable category label used by logs and metrics.

Trait Implementations

impl Clone for BuildError

fn clone(&self) -> BuildError

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for BuildError

impl Debug for BuildError

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

Formats the value using the given formatter.

impl Display for BuildError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for BuildError

impl Error for BuildError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

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

Provides type-based access to context intended for error reports.

impl PartialEq for BuildError

fn eq(&self, other: &BuildError) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for BuildError