Struct SpanLabel 

pub struct SpanLabel {
    pub span: Span<BytePos>,
    pub message: String,
    pub primary: bool,
    pub file: Option<SourceFileId>,
}

One underlined region of the user’s source, and what to say about it.

file: when a label is not about the module under check

A [codespan_reporting::diagnostic::Label] needs a file id as well as a byte range. Most labels don’t carry one themselves: a phase only ever sees one module, so its spans belong to the file that module was read from, and check_package — the only place that knows which file that is — supplies it for the whole diagnostic at render time. file: None is that case, and it covers everything built before ERR-5.

Some is the escape hatch: a label built from a SourceSpan cloned out of an Interface (via Interface::source_span) already carries its own file, generally a different one from the module being checked — “the annotation you are contradicting is over there, in Basics” — and that id is used verbatim instead of the diagnostic’s.

primary is the rustc distinction, and it applies independently of file: the caret under the thing that is wrong is primary even when it is local, and “defined here” in another file is secondary even though it is the only label pointing into that file.

Fields

span: Span<BytePos>

message: String

primary: bool

file: Option<SourceFileId>

Trait Implementations

impl Clone for SpanLabel

fn clone(&self) -> SpanLabel

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SpanLabel

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

Formats the value using the given formatter.

impl PartialEq for SpanLabel

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for SpanLabel