swc-project/swc · error · Error

Unexpected value

Error message

Unexpected value

What it means

Fired while parsing math/calc-style function values (calc, sin, cos, ...): after the single calc-sum argument, additional tokens remain before ')'. These functions accept exactly one argument, so trailing content (often a missing comma for multi-argument functions) is reported as unexpected.

Source

Thrown at crates/swc_css_parser/src/parser/values_and_units/mod.rs:213

        let mut values = Vec::new();

        let lower_fname = function_name.to_ascii_lowercase();

        match &*lower_fname {
            "calc" | "-moz-calc" | "-webkit-calc" | "sin" | "cos" | "tan" | "asin" | "acos"
            | "atan" | "sqrt" | "exp" | "abs" | "sign" => {
                self.input.skip_ws();

                let calc_sum = ComponentValue::CalcSum(self.parse()?);

                values.push(calc_sum);

                self.input.skip_ws();

                if !is!(self, EOF) {
                    let span = self.input.cur_span();

                    return Err(Error::new(span, ErrorKind::Unexpected("value")));
                }
            }
            "min" | "max" | "hypot" => {
                self.input.skip_ws();

                let calc_sum = ComponentValue::CalcSum(self.parse()?);

                values.push(calc_sum);

                loop {
                    self.input.skip_ws();

                    if is!(self, ",") {
                        values.push(ComponentValue::Delimiter(self.parse()?));

                        self.input.skip_ws();
                    } else {
                        break;

View on GitHub (pinned to 5176682b65)

Solutions

1. Pass exactly one math expression argument: 'calc(1px + 2%)'
2. Use a comma-separated multi-argument function (e.g. clamp, min, max) if several arguments are needed
3. Remove trailing tokens before the ')'

When it happens

Trigger: Thrown at crates/swc_css_parser/src/parser/values_and_units/mod.rs:213 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/98444b4d55599f54. Report an issue: GitHub.