func (s *state) evalPipeline(dot reflect.Value, pipe *parse.PipeNode) (value reflect.Value) {
	if pipe == nil {
		return
	}
	s.at(pipe)
	value = missingVal
	for _, cmd := range pipe.Cmds {
		value = s.evalCommand(dot, cmd, value) // previous value is this one's final arg.
		// If the object has type interface{}, dig down one level to the thing inside.
		if value.Kind() == reflect.Interface && value.Type().NumMethod() == 0 {