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<?php $obj = new stdClass(); $obj->bar = "xyz"; $data = array("foo" => "bar"); $key = "foo"; // the good: without and within a string echo $obj->{$data[$key]}; echo "{$obj->{$data[$key]}}"; // the bad: try { echo @$obj->${data[$key]}; // syntax error } catch (Error $e){ echo $e->getMessage(),"\n"; } // complex curly brace syntax: without and within a string echo $obj->{${'data'}[$key]}; echo "{$obj->{${'data'}[$key]}}";
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
xyzxyzUndefined constant "data" xyzxyz
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
xyzxyzxyzxyz
Output for 7.0.0 - 7.0.33
xyzxyzCannot access empty property xyzxyz
Output for 5.6.0 - 5.6.40
xyzxyz
Process exited with code 255.
Output for 5.5.0 - 5.5.38
Parse error: syntax error, unexpected '[' in /in/m8WEh on line 14
Process exited with code 255.
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215.82 ms | 401 KiB | 330 Q