Struct TtParser 

pub(crate) struct TtParser {
    cur_mps: Vec<MatcherPos>,
    next_mps: Vec<MatcherPos>,
    empty_matches: Rc<Vec<NamedMatch>>,
    found_ambiguity: bool,
}

Fields

cur_mps: Vec<MatcherPos>

The set of current mps to be processed. This should be empty by the end of a successful execution of parse_tt_inner.

next_mps: Vec<MatcherPos>

The set of newly generated mps. These are used to replenish cur_mps in the function parse_tt.

empty_matches: Rc<Vec<NamedMatch>>

Pre-allocate an empty match array, so it can be cloned cheaply for macros with many rules that have no metavars.

found_ambiguity: bool

Whether an ambiguity error has occurred.

Implementations

impl TtParser

pub(super) fn new() -> TtParser

pub(super) fn has_no_remaining_items_for_step(&self) -> bool

fn parse_tt_inner<'matcher, T: Tracker<'matcher>>( &mut self, parser: &mut Cow<'_, Parser<'_>>, matcher: &'matcher [MatcherLoc], track: &mut T, ) -> Option<ParseResult<FxHashMap<MacroRulesNormalizedIdent, NamedMatch>>>

Process the matcher positions of cur_mps until it is empty. In the process, this will produce more mps in next_mps and bb_mps.

Returns

Some(result) if everything is finished, None otherwise. Note that matches are kept track of through the mps generated.

fn match_one<'matcher, T: Tracker<'matcher>>( &mut self, parser: &mut Cow<'_, Parser<'_>>, matcher: &'matcher [MatcherLoc], mp: MatcherPos, track: &mut T, checking_for_ambiguity: bool, ) -> Option<ParseResult<FxHashMap<MacroRulesNormalizedIdent, NamedMatch>>>

Match a single MatcherPos.

If a meta-variable is encountered and checking_for_ambiguity is false, cur_mps will be drained to eagerly check for ambiguity, and parser will be modified.

fn check_for_ambiguity<'matcher, R, T: Tracker<'matcher>>( &mut self, parser: &mut Cow<'_, Parser<'_>>, matcher: &'matcher [MatcherLoc], track: &mut T, checking_for_ambiguity: bool, ) -> ControlFlow<Option<ParseResult<R>>>

Look for ambiguity before parsing a non-terminal.

• When checking_for_ambiguity: immediately an ambiguity error.
• Otherwise: eagerly consumes Self::cur_mps to check for ambiguity.

If ControlFlow::Continue is returned, ambiguity has not been detected.

pub(super) fn parse_tt<'matcher, T: Tracker<'matcher>>( &mut self, parser: &mut Cow<'_, Parser<'_>>, matcher: &'matcher [MatcherLoc], track: &mut T, ) -> ParseResult<FxHashMap<MacroRulesNormalizedIdent, NamedMatch>>

Match the token stream from parser against matcher.

fn nt_parsing_error<R>(&self, loc: &MatcherLoc, err: Diag<'_>) -> ParseResult<R>

fn nameize<I: Iterator<Item = NamedMatch>>( &self, matcher: &[MatcherLoc], res: I, ) -> FxHashMap<MacroRulesNormalizedIdent, NamedMatch>

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: 64 bytes