3v4l.org

run code in 300+ PHP versions simultaneously
<?php trait base_trait { protected $prop = []; function __construct() { var_dump($this->prop); } } class base_class { use base_trait; } class test_class_property extends base_class { protected $prop = ['a' => 'b']; } trait overlay_trait { protected $prop = ['a' => 'b']; } class test_class_overlay extends base_class { use overlay_trait; } new base_class; new test_class_property; new test_class_overlay;
Output for 7.0.0 - 7.0.26, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
Fatal error: base_class and overlay_trait define the same property ($prop) in the composition of test_class_overlay. However, the definition differs and is considered incompatible. Class was composed in /in/7qdmA on line 29
Process exited with code 255.
preferences:
149.65 ms | 408 KiB | 5 Q