marser 0.1.1

Parser combinator toolkit with matcher-level backtracking and rich error reporting.
Documentation 
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use crate::{
    error::{MatcherRunError, error_handler::ErrorHandler},
    input::{Input, InputStream},
    matcher::{MatchRunner, MatcherCombinator},
    parser::{Parser, ParserCombinator},
};

/// Matcher wrapper that succeeds when `parser` succeeds and discards its output.
#[derive(Clone, Debug)]
pub struct IgnoreResult<Parser> {
    parser: Parser,
}

impl<Parser> MatcherCombinator for IgnoreResult<Parser> where Parser: ParserCombinator {}

impl<Parser> IgnoreResult<Parser> {
    /// Wrap `parser`.
    pub fn new(parser: Parser) -> Self {
        Self { parser }
    }
}

impl<'src, Inp: Input<'src>, MRes, Pars> super::internal::MatcherImpl<'src, Inp, MRes>
    for IgnoreResult<Pars>
where
    Pars: Parser<'src, Inp>,
{
    const CAN_MATCH_DIRECTLY: bool = true;
    const HAS_PROPERTY: bool = false;
    const CAN_FAIL: bool = Pars::CAN_FAIL;

    #[inline]
    fn match_with_runner<'a, Runner>(
        &'a self,
        runner: &mut Runner,
        error_handler: &mut impl ErrorHandler,
        input: &mut InputStream<'src, Inp>,
    ) -> Result<bool, MatcherRunError>
    where
        Runner: MatchRunner<'a, 'src, Inp, MRes = MRes>,
        'src: 'a,
    {
        let result = self
            .parser
            .parse(runner.get_parser_context(), error_handler, input)?;
        Ok(result.is_some())
    }
}