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run code in 300+ PHP versions simultaneously
<?php class Foo { private $items; function __construct($a) { $this->items = []; $this->items['params'] = []; $this->items['a'] = $a; } function __get($name) { if ($name === 'a') { return $this->items['a']; } return null; } function __isset($a) { var_dump($a); return isset($this->items->params[$a]); } function bar() { if (isset($this->a['xyz'])) { return 'yes'; } return 'no'; } function baz() { $tmp = $this->a; if (isset($tmp['xyz'])) { return 'yes'; } return 'no'; } } $f = new Foo(['xyz' => true]); var_dump($f->bar()); var_dump($f->baz());
based on r9QFk
Output for 7.0.6 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.27, 7.4.0 - 7.4.15, 8.0.0 - 8.0.3
string(1) "a" string(2) "no" string(3) "yes"
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.5
string(3) "yes" string(3) "yes"