mpl 0.3.0

One-rule TDPL/PEG parsing language with a static-codegen backend (FastParse) that beats pest, peg, nom, winnow, and chumsky on equal-work benchmarks.
Documentation 
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use crate::span::{Len, Span, Start, StartAndLenSpan};
use crate::symbols::terminal::StartAndLenResult;
use crate::symbols::{Metasymbol, Terminal};
use crate::trees::AST;

#[derive(Copy, Clone, Debug, PartialEq)]
pub enum StrTerminal<'a> {
    Char(char),
    Str(&'a str),
}

impl From<char> for StrTerminal<'_> {
    fn from(value: char) -> Self {
        Self::Char(value)
    }
}

impl<'a> From<&'a str> for StrTerminal<'a> {
    fn from(value: &'a str) -> Self {
        Self::Str(value)
    }
}

impl<'a, V, P, L, O> Terminal<'a, str, V, StartAndLenSpan<P, L>, P, O> for StrTerminal<'a>
where
    P: Start<str, L>,
    L: Len<str, P>,
{
    fn eval(&self, input: &'a str, pos: P, max_pos: &P) -> StartAndLenResult<V, P, L, O> {
        let eval_from = |len: usize, string: &str| {
            let start = pos.clone();
            let pos: usize = P::into_usize(pos, input);
            let span = StartAndLenSpan::from_lo_len(start, len, input);
            let hi = span.hi(input);
            let ast = AST::from_leaf(Metasymbol::Omit.into(), span);
            if &hi <= max_pos {
                if let Some(s) = input.get(pos..pos + len) {
                    if s == string {
                        return Ok(ast);
                    }
                }
            }
            Err(ast)
        };

        match self {
            StrTerminal::Char(c) => eval_from(c.len_utf8(), &c.to_string()),
            StrTerminal::Str(s) => eval_from(s.len(), s),
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn convert() {
        let c = StrTerminal::from('A');
        let s = StrTerminal::from("abc");

        assert_eq!(c, StrTerminal::Char('A'));
        assert_eq!(s, StrTerminal::Str("abc"));
    }
}