swc-project/swc · error · Error

Expected function or ident tokens

Error message

Expected function or ident tokens

What it means

Fired at the end of pseudo-class selector parsing: a pseudo-class must be either a functional form (a Function token, parsed into name + children) or a simple ident; the current token was neither, so no PseudoClassSelector could be built. Input at fault is a `:` followed by a non-ident, non-function token, e.g. `: 5` or `:.`.

Source

Thrown at crates/swc_css_parser/src/parser/selectors/mod.rs:1064

                name: Ident {
                    span: Span::new(fn_span.lo, fn_span.hi - BytePos(1)),
                    value: names.0,
                    raw: Some(names.1),
                },
                children: Some(children),
            })
        } else if is!(self, Ident) {
            let name: Ident = self.parse()?;

            Ok(PseudoClassSelector {
                span: span!(self, span.lo),
                name,
                children: None,
            })
        } else {
            let span = self.input.cur_span();

            Err(Error::new(
                span,
                ErrorKind::Expected("function or ident tokens"),
            ))
        }
    }
}

impl<I> Parse<PseudoElementSelector> for Parser<I>
where
    I: ParserInput,
{
    fn parse(&mut self) -> PResult<PseudoElementSelector> {
        let span = self.input.cur_span();

        expect!(self, ":");
        expect!(self, ":");

        if is!(self, Function) {

View on GitHub (pinned to 5176682b65)

Solutions

1. Write pseudo-classes as :ident or :function(args)
2. Surface the diagnostic from the parse result
3. Fix the selector

When it happens

Trigger: Thrown at crates/swc_css_parser/src/parser/selectors/mod.rs:1064 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of swc-project/swc@5176682b65 (2026-08-17). Data as JSON: /api/errors/eec4d6785e3b010b. Report an issue: GitHub.