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<?php class IteratorWithFilter { public $generator; public function __construct(array $data) { $this->generator = new \ArrayIterator($data); } public function filter() { $this->generator = new \CallbackFilterIterator($this->generator, function ($row) { return true; }); return $this; } } function createIterator() { $iter = new IteratorWithFilter([['a'], ['b']]); return $iter->filter(); } for ($i = 0; $i < 50 * 1000; $i++) { createIterator(); if (($i % 1000) === 0) { // gc_collect_cycles(); // explicit GC does not help... echo round(memory_get_usage() / (1024 * 1024), 3) . " MiB\n"; } }

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35.64 ms | 402 KiB | 5 Q