radiance · commit

lang: Parse subscripts in normal context

55278d55842a314017ab0cfc216c2db29b60a391bfab0035c1c093909f4f9ec6

Subscript and slice bounds inherited the enclosing condition
context. A record literal used to compute a bracketed index was
mistaken for the condition body and rejected.

Parse expressions between subscript brackets in normal expression
context and restore the enclosing context afterward.

Assisted-by: Codex:gpt-5.6-sol

Alexis Sellier committed 1 month ago 1 parent 4e1403a0

lib/std/lang/parser.rad +3 -0

/// Parse array subscript or slice expression after `[`.
fn parseSubscriptOrSlice(p: *mut Parser, container: *ast::Node) -> *ast::Node
    throws (ParseError)
{
    try expect(p, scanner::TokenKind::LBracket, "expected `[`");
    let saved = p.context;
    set p.context = Context::Normal;

    let mut index: *ast::Node = undefined;

    if consume(p, scanner::TokenKind::DotDot) {
        // Either `..` or `..end`.

            // Just `n` - regular indexing.
            set index = startExpr;
        }
    }
    try expect(p, scanner::TokenKind::RBracket, "expected `]` after array index");
    set p.context = saved;

    return node(p, ast::NodeValue::Subscript { container, index });
}

/// Parse postfix operators (eg. field access, function call etc.)

test/tests/parser.condition.subscript.record.rad added +12 -0

1	+	//! returns: 0
2	+	//! Bracketed subscript expressions may contain record literals in a condition.
3	+
4	+	record Index { value: u32 }
5	+
6	+	@default fn main() -> i32 {
7	+	let values: [i32; 1] = [7];
8	+	if values[Index { value: 0 }.value] == 7 {
9	+	return 0;
10	+	}
11	+	return 1;
12	+	}

339	339		/// Parse array subscript or slice expression after `[`.
340	340		fn parseSubscriptOrSlice(p: mut Parser, container: ast::Node) -> *ast::Node
341	341		throws (ParseError)
342	342		{
343	343		try expect(p, scanner::TokenKind::LBracket, "expected `[`");
	344	+	let saved = p.context;
	345	+	set p.context = Context::Normal;
344	346
345	347		let mut index: *ast::Node = undefined;
346	348
347	349		if consume(p, scanner::TokenKind::DotDot) {
348	350		// Either `..` or `..end`.

370	372		// Just `n` - regular indexing.
371	373		set index = startExpr;
372	374		}
373	375		}
374	376		try expect(p, scanner::TokenKind::RBracket, "expected `]` after array index");
	377	+	set p.context = saved;
375	378
376	379		return node(p, ast::NodeValue::Subscript { container, index });
377	380		}
378	381
379	382		/// Parse postfix operators (eg. field access, function call etc.)