* Remove unnecessary reference assigment
Proposed code is PHP5 and PHP7 compatible. PHP5 interpreted `$e->$type[$attr]` as `$e->{$type[$attr]}`, but the expected behavior based on workaround is consistent with PHP7 interpretation: `($e->$type)[$attr]`. By using curly braces `{$e->$type}[$attr]` there is a forced interpretation order working for both versions.
Details can be found on https://www.php.net/manual/en/migration70.incompatible.php (section "Changes to the handling of indirect variables, properties, and methods")
* Fix syntax
Use correct syntax for indirect variable evaluation order change.