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<?php $x = new class() { public $callCounters = []; public function call($index) { if (!isset($this->callCounters[$index])) { $this->callCounters[$index] = 0; } ++$this->callCounters[$index]; } }; $indexes = range('a','e'); foreach($indexes as $index) { for($i = 0; $i <= 2; ++$i) { $x->call($index); } } var_dump($x->callCounters);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
array(5) { ["a"]=> int(3) ["b"]=> int(3) ["c"]=> int(3) ["d"]=> int(3) ["e"]=> int(3) }

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