rib-lang 0.0.4

Rib language: parser, typechecker, compiler, and interpreter for WebAssembly component (WIT) workflows
Documentation 
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use crate::parser::errors::RibParseError;
use crate::parser::rib_expr::rib_expr;
use crate::rib_source_span::GetSourcePosition;
use crate::Expr;
use combine::parser::char::{char, spaces};
use combine::{attempt, sep_end_by, ParseError, Parser};

// Get all expressions in a block
// that doesn't have a return type
// It is not a valid rib by itself, unless we resolve the return collection type
// aligning to Rib grammar spec
pub fn block_without_return<Input>() -> impl Parser<Input, Output = Vec<Expr>>
where
    Input: combine::Stream<Token = char>,
    RibParseError: Into<
        <Input::Error as ParseError<Input::Token, Input::Range, Input::Position>>::StreamError,
    >,
    Input::Position: GetSourcePosition,
{
    spaces()
        .with(sep_end_by(attempt(rib_expr()), char(';').skip(spaces())))
        .map(|block: Vec<Expr>| block)
}

#[cfg(test)]
mod tests {
    use bigdecimal::BigDecimal;
    use test_r::test;

    use super::*;
    use combine::stream::position;
    use combine::EasyParser;

    #[test]
    fn test_block_without_return() {
        let input = r#"
        let x = 1;
        let y = 2;
        x + y;
        "#;
        let expr = block_without_return()
            .easy_parse(position::Stream::new(input))
            .unwrap()
            .0;

        let expected = vec![
            Expr::let_binding("x", Expr::number(BigDecimal::from(1)), None),
            Expr::let_binding("y", Expr::number(BigDecimal::from(2)), None),
            Expr::plus(
                Expr::identifier_global("x", None),
                Expr::identifier_global("y", None),
            ),
        ];
        assert_eq!(expr, expected);
    }
}