if err != nil {
		return err
	}

	if err := p.writeEnd(start.Name); err != nil {
		return err
	}

	return p.cachedWriteError()
}

// marshalAttr marshals an attribute with the given name and value, adding to start.Attr.
func (p *printer) marshalAttr(start *StartElement, name Name, val reflect.Value) error {
	if val.CanInterface() && val.Type().Implements(marshalerAttrType) {