Online PHP editor | output for 33Y0P

<?php phpversion() >= "7.0.1" or die(); $obj = new stdClass(); $obj->bar = "abc"; $data = array("foo" => "bar"); $key = "foo"; // the bad: /*try { echo $obj->${data[$key]}; // syntax error } catch (Error $e){ echo $e->getMessage(),"\n"; } */ // uvs - the good: without and within a string echo $obj->{$data[$key]},"\n"; echo "{$obj->{$data[$key]}}\n"; $obj->bar = "xyz"; // uvs - complex curly brace syntax: without and within a string echo $obj->{${'data'}[$key]},"\n"; echo "{$obj->{${'data'}[$key]}}\n"; echo "{$obj->{${data}[$key]}}\n";