Struct CollectTrackerAndEmitter 

struct CollectTrackerAndEmitter<'dcx, 'matcher> {
    macro_name: Ident,
    dcx: DiagCtxtHandle<'dcx>,
    current: Option<(WhichMatcher, &'matcher [MatcherLoc])>,
    matches: FxHashSet<SuccessfulMatch>,
    remaining_matcher: Option<&'matcher MatcherLoc>,
    best_failure: Option<BestFailure>,
    root_span: Span,
    result: Option<(Span, ErrorGuaranteed)>,
}

The tracker used for the slow error path that collects useful info for diagnostics.

Fields

macro_name: Ident

dcx: DiagCtxtHandle<'dcx>

current: Option<(WhichMatcher, &'matcher [MatcherLoc])>

The matcher currently being parsed.

matches: FxHashSet<SuccessfulMatch>

Matches of MatcherLocs that successfully consumed input from the parser.

This accumulates all calls to Tracker::matched_one(). It is used to identify all competing matches for ambiguity errors.

remaining_matcher: Option<&'matcher MatcherLoc>

best_failure: Option<BestFailure>

Which arm’s failure should we report? (the one furthest along)

root_span: Span

result: Option<(Span, ErrorGuaranteed)>

Implementations

impl<'dcx> CollectTrackerAndEmitter<'dcx, '_>

fn new(macro_name: Ident, dcx: DiagCtxtHandle<'dcx>, root_span: Span) -> Self

Trait Implementations

impl<'dcx, 'matcher> Tracker<'matcher> for CollectTrackerAndEmitter<'dcx, 'matcher>

fn prepare( &mut self, which_matcher: WhichMatcher, matcher: &'matcher [MatcherLoc], )

Provide context on the arm that’s about to be matched.

fn before_match_loc(&mut self, parser: &TtParser, matcher: &'matcher MatcherLoc)

This is called before trying to match next MatcherLoc on the current token.

fn matched_one(&mut self, parser: &Parser<'_>, loc_index: usize)

A MatcherLoc successfully consumed input from the parser.

fn after_arm( &mut self, result: &ParseResult<FxHashMap<MacroRulesNormalizedIdent, NamedMatch>>, )

This is called after an arm has been parsed, either successfully or unsuccessfully. When this is called, before_match_loc was called at least once (with a MatcherLoc::Eof).

fn failure(&mut self, parser: &Parser<'_>)

The arm could not be matched successfully.

fn ambiguity(&mut self, parser: &Parser<'_>)

An ambiguity error occurred.

fn description() -> &'static str

For tracing.

fn recovery() -> Recovery

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: 200 bytes