mpl-macro 0.2.1

Derive parsers from MPL's one-rule grammar files. Includes the FastParse static-codegen backend (cascade detection, first-byte dispatch, Squirrel left recursion).
Documentation 
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use mpl::parser::Parser;
use mpl::span::StartAndLenSpan;
use mpl::trees::AST;
use mpl_macro::Parse;

#[derive(Parse, Debug)]
#[mplg = "tests/parentheses.mplg"]
pub struct ParenParser;

type ParenSpan = StartAndLenSpan<u32, u16>;
type ParenAst = AST<ParenVariable, ParenSpan, ()>;
type ParenParseResult = Result<ParenAst, ParenAst>;

enum ParseResult {
    Ok,
    Err,
}

const INPUTS: [(&str, ParseResult); 8] = [
    // Ok
    ("", ParseResult::Ok),
    ("()", ParseResult::Ok),
    ("()(())", ParseResult::Ok),
    ("(()(()))", ParseResult::Ok),
    // Err
    ("(", ParseResult::Err),
    (")", ParseResult::Err),
    ("()())", ParseResult::Err),
    ("(()(())))", ParseResult::Err),
];

#[test]
fn derive_grammar_from_file() {
    let parser = ParenParser;

    for input in INPUTS {
        let input_data = input.0.as_bytes();
        let parse_result = input.1;
        // all of the span
        let all_of_the_span =
            StartAndLenSpan::<u32, u16>::from_start_len(0, input_data.len() as u16);
        let result: ParenParseResult = parser.parse(
            input_data,
            &ParenRules,
            &ParenVariable::Open,
            &all_of_the_span,
        );
        match parse_result {
            ParseResult::Ok => assert!(result.is_ok()),
            ParseResult::Err => assert!(result.is_err()),
        }
    }
}