Enum rustc_error_messages::SubdiagnosticMessage

pub enum SubdiagnosticMessage {
    Str(String),
    FluentIdentifier(Cow<'static, str>),
    FluentAttr(Cow<'static, str>),
}

Abstraction over a message in a subdiagnostic (i.e. label, note, help, etc) to support both translatable and non-translatable diagnostic messages.

Translatable messages for subdiagnostics are typically attributes attached to a larger Fluent message so messages of this type must be combined with a DiagnosticMessage (using DiagnosticMessage::with_subdiagnostic_message) before rendering. However, subdiagnostics from the SessionSubdiagnostic derive refer to Fluent identifiers directly.

Variants

Str(String)

Non-translatable diagnostic message.

FluentIdentifier(Cow<'static, str>)

Identifier of a Fluent message. Instances of this variant are generated by the SessionSubdiagnostic derive.

FluentAttr(Cow<'static, str>)

Attribute of a Fluent message. Needs to be combined with a Fluent identifier to produce an actual translated message. Instances of this variant are generated by the fluent_messages macro.

https://projectfluent.org/fluent/guide/attributes.html

Trait Implementations

impl<S: Into<String>> From<S> for SubdiagnosticMessage

From impl that enables existing diagnostic calls to functions which now take impl Into<SubdiagnosticMessage> to continue to work as before.

fn from(s: S) -> Self

Converts to this type from the input type.

impl Into<SubdiagnosticMessage> for DiagnosticMessage

Translating into a subdiagnostic message from a diagnostic message is a little strange - but the subdiagnostic functions (e.g. span_label) take a SubdiagnosticMessage and the subdiagnostic derive refers to typed identifiers that are DiagnosticMessages, so need to be able to convert between these, as much as they’ll be converted back into DiagnosticMessage using with_subdiagnostic_message eventually. Don’t use this other than for the derive.

fn into(self) -> SubdiagnosticMessage

Converts this type into the (usually inferred) input type.

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: 32 bytes

Size for each variant:

• Str: 24 bytes
• FluentIdentifier: 24 bytes
• FluentAttr: 24 bytes