3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php /** * Run it: php r30.php * Run it with a custom number of rows: php r30.php <number> * Have fun :) */ function createRows($numRows, $rule) { $getNextRow = function ($currRow) use ($rule) { $nextRow = [0, 0]; for ($i = 1, $iMax = count($currRow) - 1; $i < $iMax; $i++) { $nextRow[] = $rule[$currRow[$i - 1] . $currRow[$i] . $currRow[$i + 1]]; } array_push($nextRow, 0, 0); return $nextRow; }; $rows[0] = [0, 0, 1, 0, 0]; for ($i = 1; $i <= $numRows; $i++) { $rows[$i] = $getNextRow($rows[$i - 1]); } return $rows; } function displayRows($rows, $isDownwards, $micSleep) { $rowCount = count($rows); $getRow = function ($rows, $isDownwards) use ($rowCount) { if ($isDownwards === true) { for ($i = 0; $i < $rowCount; $i++) { yield [$i, $rows[$i]]; } } else { for ($i = $rowCount - 1; $i >= 0; $i--) { yield [$i, $rows[$i]]; } } } foreach ($getRow($rows, $isDownwards) as [$pad, $row]) { echo str_repeat(' ', $rowCount - $pad); foreach ($row as $cell) { echo $cell === 1 ? '█' : ' '; } echo PHP_EOL; usleep($micSleep); } } // https://en.wikipedia.org/wiki/Rule_30 const RULE_30 = [ '111' => 0, '110' => 0, '101' => 0, '100' => 1, '011' => 1, '010' => 1, '001' => 1, '000' => 0, ]; $numRows = isset($argv[1]) && (int)$argv[1] > 0 && (int)$argv[1] <= 1000 ? (int)$argv[1] : 80; $rows = createRows($numRows, RULE_30); while (true) { displayRows($rows, true, 5000); displayRows($rows, false, 5000); }
based on bO716
Output for 5.6.0 - 5.6.30, 7.0.0 - 7.1.7
Parse error: syntax error, unexpected 'foreach' (T_FOREACH) in /in/GM147 on line 36
Process exited with code 255.
Output for hhvm-3.15.4
Fatal error: Uncaught Error: syntax error, unexpected T_FOREACH in /in/GM147:36 Stack trace: #0 {main}
Process exited with code 255.