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<?php $decurrying = function ($arg = null, $acc = '') use (&$decurrying) { return $arg === null ? $acc : function ($arg = null, $acc = '') use (&$decurrying) { return $decurrying($arg, $acc . $arg); }; }; $result = $decurrying(1)(3)(3)(8)(); var_dump($result);
Output for 7.0.0 - 7.0.20, 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
string(0) ""

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