marser 0.1.1

Parser combinator toolkit with matcher-level backtracking and rich error reporting.
Documentation 
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use std::marker::PhantomData;

use crate::{
    error::{MatcherRunError, error_handler::ErrorHandler},
    input::{Input, InputStream},
    matcher::{MatcherCombinator, internal::MatcherImpl, runner::MatchRunner},
    parser::{Parser, ParserCombinator, capture::MatchResult},
};

use super::property::Property;

/// [`crate::matcher::Matcher`] that runs parser `Pars` and stores its output with `Prop`.
#[derive(Clone)]
pub struct ResultBinder<Pars, Prop, Inp> {
    pub(super) parser: Pars,
    pub(super) property: Prop,
    pub(super) _phantom: PhantomData<Inp>,
}

impl<Pars, Prop, Inp> std::fmt::Debug for ResultBinder<Pars, Prop, Inp> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("ResultBinder").finish()
    }
}

impl<Pars, Prop, Inp> MatcherCombinator for ResultBinder<Pars, Prop, Inp> where
    Pars: ParserCombinator
{
}

impl<Pars, Prop, Inp> ResultBinder<Pars, Prop, Inp> {
    /// Wraps `parser` and `property`.
    pub fn new(parser: Pars, property: Prop) -> Self {
        Self {
            parser,
            property,
            _phantom: PhantomData,
        }
    }
}

/// Convenience constructor for [`ResultBinder`].
pub fn bind_result<Pars, Prop, Inp>(parser: Pars, property: Prop) -> ResultBinder<Pars, Prop, Inp> {
    ResultBinder::new(parser, property)
}

impl<'src, Inp: Input<'src> + 'src, Pars, Prop, MRes> MatcherImpl<'src, Inp, MRes>
    for ResultBinder<Pars, Prop, Inp>
where
    Pars: Parser<'src, Inp> + 'src,
    Inp: Input<'src> + Clone,
    MRes: MatchResult,
    Prop: Property<Pars::Output, MRes> + Clone + 'src,
{
    const CAN_MATCH_DIRECTLY: bool = true;
    const HAS_PROPERTY: bool = true;
    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,
    {
        if let Some(result) =
            self.parser
                .parse(runner.get_parser_context(), error_handler, input)?
        {
            let bound = self.property.bind_result(result);
            runner.register_result(bound);
            Ok(true)
        } else {
            Ok(false)
        }
    }
}