private function loc(Token $startToken)
    {
        if (empty($this->lexer->options['noLocation'])) {
            return new Location($startToken, $this->lexer->lastToken, $this->lexer->source);
        }

        return null;
    }
private function loc(Token $startToken)
    {
        if (empty($this->lexer->options['noLocation'])) {
            return new Location($startToken, $this->lexer->lastToken, $this->lexer->source);
        }

        return null;
    }
Returns a location object, used to identify the place in
the source that created a given parsed object.

@return Location|null