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run code in 300+ PHP versions simultaneously
<?php class Foo { protected $titleInfo = []; /** @return array */ public function bar() { $key = ''; if ( !isset( $this->titleInfo[$key] ) ) { $this->titleInfo[$key] = [ 42 ]; } return $this->titleInfo[$key]; # The critical line } } $value = ( new Foo )->bar(); var_dump( $value );
based on vS7Dn
Output for 7.1.25 - 7.1.30, 7.2.0 - 7.2.33, 7.3.0 - 7.3.21, 7.4.0 - 7.4.10, 8.0.0alpha1 - beta3
array(1) { [0]=> int(42) }