Enum rustc_errors::Level

pub enum Level {
    Bug,
    Fatal,
    Error,
    DelayedBug,
    GoodPathDelayedBug,
    ForceWarning(Option<LintExpectationId>),
    Warning,
    Note,
    OnceNote,
    Help,
    OnceHelp,
    FailureNote,
    Allow,
    Expect(LintExpectationId),
}

Level is_error EmissionGuarantee Top-level Sub Used in lints?

---

Bug yes BugAbort yes - - Fatal yes FatalAbort/FatalError(*) yes - - Error yes ErrorGuaranteed yes - yes DelayedBug yes ErrorGuaranteed yes - - GoodPathDelayedBug - () yes - - ForceWarning - () yes - lint-only Warning - () yes yes yes Note - () rare yes - OnceNote - () - yes lint-only Help - () rare yes - OnceHelp - () - yes lint-only FailureNote - () rare - - Allow - () yes - lint-only Expect - () yes - lint-only

(*) FatalAbort normally, FatalError in the non-aborting “almost fatal” case that is occasionally used.

Variants

Bug

For bugs in the compiler. Manifests as an ICE (internal compiler error) panic.

Fatal

An error that causes an immediate abort. Used for things like configuration errors, internal overflows, some file operation errors.

Error

An error in the code being compiled, which prevents compilation from finishing. This is the most common case.

DelayedBug

This is a strange one: lets you register an error without emitting it. If compilation ends without any other errors occurring, this will be emitted as a bug. Otherwise, it will be silently dropped. I.e. “expect other errors are emitted” semantics. Useful on code paths that should only be reached when compiling erroneous code.

GoodPathDelayedBug

Like DelayedBug, but weaker: lets you register an error without emitting it. If compilation ends without any other diagnostics being emitted (and without an expected lint being suppressed), this will be emitted as a bug. Otherwise, it will be silently dropped. I.e. “expect other diagnostics are emitted (or suppressed)” semantics. Useful on code paths that should only be reached when emitting diagnostics, e.g. for expensive one-time diagnostic formatting operations.

FIXME(nnethercote) good path delayed bugs are semantically strange: if printed they produce an ICE, but they don’t satisfy is_error and they don’t guarantee an error is emitted. Plus there’s the extra complication with expected (suppressed) lints. They have limited use, and are used in very few places, and “good path” isn’t a good name. It would be good to remove them.

ForceWarning(Option<LintExpectationId>)

A force-warn lint warning about the code being compiled. Does not prevent compilation from finishing.

The LintExpectationId is used for expected lint diagnostics. In all other cases this should be None.

Warning

A warning about the code being compiled. Does not prevent compilation from finishing. Will be skipped if can_emit_warnings is false.

Note

A message giving additional context.

OnceNote

A note that is only emitted once.

Help

A message suggesting how to fix something.

OnceHelp

A help that is only emitted once.

FailureNote

Similar to Note, but used in cases where compilation has failed. When printed for human consumption, it doesn’t have any kind of note: label.

Allow

Only used for lints.

Expect(LintExpectationId)

Only used for lints.

Implementations

impl Level

pub(crate) fn color(self) -> ColorSpec

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

pub fn is_failure_note(&self) -> bool

pub fn get_expectation_id(&self) -> Option<LintExpectationId>

pub(crate) fn can_be_top_or_sub(&self) -> (bool, bool)

Trait Implementations

impl Clone for Level

fn clone(&self) -> Level

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Level

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

Formats the value using the given formatter.

impl<__D: SpanDecoder> Decodable<__D> for Level

fn decode(__decoder: &mut __D) -> Self

impl Display for Level

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

Formats the value using the given formatter.

impl<__E: SpanEncoder> Encodable<__E> for Level

fn encode(&self, __encoder: &mut __E)

impl Hash for Level

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl IntoDiagnosticArg for Level

fn into_diagnostic_arg(self) -> DiagnosticArgValue

impl PartialEq for Level

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Level

impl Eq for Level

impl StructuralPartialEq for Level

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 24 bytes

Size for each variant:

• Bug: 0 bytes
• Fatal: 0 bytes
• Error: 0 bytes
• DelayedBug: 0 bytes
• GoodPathDelayedBug: 0 bytes
• ForceWarning: 20 bytes
• Warning: 0 bytes
• Note: 0 bytes
• OnceNote: 0 bytes
• Help: 0 bytes
• OnceHelp: 0 bytes
• FailureNote: 0 bytes
• Allow: 0 bytes
• Expect: 20 bytes