Function validate_syn_argsep

core/src/compiler/args.rs:44–94

Validates an argument separator against the expected syntax. `syn` contains the details about the separator syntax that is accepted. `end_ok` indicates whether an `ArgSep::End` is acceptable. This is true for repeated arguments, where `End` terminates the argument sequence, and false for singular arguments, where `End` should only be accepted by `ArgSepSyntax::End`. `is_last` indicates whether

(
    md: &Rc<CallableMetadata>,
    syn: &ArgSepSyntax,
    end_ok: bool,
    is_last: bool,
    sep: ArgSep,
    sep_pos: LineCol,
)

///
/// `sep` and `sep_pos` are the details about the separator being validated.
fn validate_syn_argsep(
    md: &Rc<CallableMetadata>,
    syn: &ArgSepSyntax,
    end_ok: bool,
    is_last: bool,
    sep: ArgSep,
    sep_pos: LineCol,
) -> Result<()> {
    debug_assert!(
        (!is_last || sep == ArgSep::End) && (is_last || sep != ArgSep::End),
        "Parser can only supply an End separator in the last argument"
    );

    match syn {
        ArgSepSyntax::Exactly(exp_sep) => {
            debug_assert!(*exp_sep != ArgSep::End, "Use ArgSepSyntax::End");
            if sep == *exp_sep || (sep == ArgSep::End && end_ok) {
                Ok(())
            } else {
                Err(Error::CallableSyntax(sep_pos, md.as_ref().clone()))
            }
        }

        ArgSepSyntax::OneOf(exp_seps) => {
            if sep == ArgSep::End {
                if end_ok {
                    return Ok(());
                }
                return Err(Error::CallableSyntax(sep_pos, md.as_ref().clone()));
            }

            let mut found = false;
            for exp_sep in *exp_seps {
                debug_assert!(*exp_sep != ArgSep::End, "Use ArgSepSyntax::End");
                if sep == *exp_sep {
                    found = true;
                    break;
                }
            }
            if !found {
                return Err(Error::CallableSyntax(sep_pos, md.as_ref().clone()));
            }
            Ok(())
        }

        ArgSepSyntax::End => {
            debug_assert!(is_last);
            Ok(())
        }
    }
}

/// Pre-allocates one local variable for a command output argument, setting its to its default
/// value.