matryer/xbar · error

alternate

Error message

alternate

What it means

This error occurs when the "alternate" key in a plugin item's parameter string cannot be parsed as a boolean. setValueByKey calls parseBool for the alternate value and wraps the failure with the key "alternate". It means the alternate= value (controlling alternate dropdown-line display) is not a valid boolean literal.

Source

Thrown at pkg/plugins/item_params.go:243

			return errors.Wrap(err, key)
		}
	case "length":
		val, err := parseInt(value)
		if err != nil {
			return errors.Wrap(err, key)
		}
		p.Length = val
	case "trim":
		var err error
		p.Trim, err = parseBool(value)
		if err != nil {
			return errors.Wrap(err, key)
		}
	case "alternate":
		var err error
		p.Alternate, err = parseBool(value)
		if err != nil {
			return errors.Wrap(err, key)
		}
	case "emojize":
		var err error
		p.Emojize, err = parseBool(value)
		if err != nil {
			return errors.Wrap(err, key)
		}
	case "ansi":
		var err error
		p.ANSI, err = parseBool(value)
		if err != nil {
			return errors.Wrap(err, key)
		}
	default:
		if strings.HasPrefix(key, "param") {
			paramIndex, err := strconv.Atoi(key[5:])
			if err != nil {
				return errors.Errorf("bad parameter: %s (should be paramN)", key)

View on GitHub (pinned to d624239058)

Solutions

1. Set alternate=true or alternate=false (1/0, t/f also accepted).
2. Fix stray characters or whitespace around the value.
3. Guard the emitting script so it writes a literal true/false instead of an empty or unexpanded value.
4. Remove the key if you want the default behavior.

Example fix

// before
params := "alternate=yes"
// after
params := "alternate=true"

re := regexp.MustCompile(`alternate=(true|false|1|0|t|f|TRUE|FALSE|True|False|T|F)\b`)
if strings.Contains(params, "alternate=") && !re.MatchString(params) {
    return errors.New("alternate must be true or false")
}

func isGoBool(s string) bool {
    _, err := strconv.ParseBool(strings.TrimSpace(s))
    return err == nil
}

if err := item.ParseParams(raw); err != nil {
    if strings.Contains(err.Error(), "alternate") {
        log.Printf("bad alternate value in %q: %v", raw, err)
        raw = removeParam(raw, "alternate")
    }
}

When it happens

Trigger: Parsing a param string containing 'alternate=yes', 'alternate=TRUE.' with stray characters, 'alternate=' (empty), or any other non-boolean value.

Common situations: Authors toggling alternate line display copy conventions from YAML (yes/no) or JSON (true with quotes stripped), or scripts emit an empty value when a flag variable is unset.

Related errors

• refresh
• dropdown
• trim
• emojize
• ansi

AI-assisted analysis of matryer/xbar@d624239058 (2026-09-02). Data as JSON: /api/errors/e393ba8873b005fd. Report an issue: GitHub.