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<?php $tree = array( 1 => array( 'parent_id' => null, 'name' => 'root', 'depth' => 0, ), 11 => array( 'parent_id' => 1, 'name' => 'a', 'depth' => 1, ), 12 => array( 'parent_id' => 1, 'name' => 'b', 'depth' => 1, ), 111 => array( 'parent_id' => 11, 'name' => 'aa', 'depth' => 2, ), 2 => array( 'parent_id' => null, 'name' => 'other root', 'depth' => 0, ) ); foreach ($tree as $key => &$sub) { if (isset($sub['parent_id'])) { $tree[$sub['parent_id']]['children'][$key] = &$sub; } } unset($sub); // unset the reference to make sure to not overwrite it later... // now remove the entries with parents foreach ($tree as $key => $sub) { if (isset($sub['parent_id'])) unset($tree[$key]); } var_dump($tree);
Output for 5.0.0 - 7.1.0
array(2) { [1]=> array(4) { ["parent_id"]=> NULL ["name"]=> string(4) "root" ["depth"]=> int(0) ["children"]=> array(2) { [11]=> array(4) { ["parent_id"]=> int(1) ["name"]=> string(1) "a" ["depth"]=> int(1) ["children"]=> array(1) { [111]=> array(3) { ["parent_id"]=> int(11) ["name"]=> string(2) "aa" ["depth"]=> int(2) } } } [12]=> array(3) { ["parent_id"]=> int(1) ["name"]=> string(1) "b" ["depth"]=> int(1) } } } [2]=> array(3) { ["parent_id"]=> NULL ["name"]=> string(10) "other root" ["depth"]=> int(0) } }
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '&', expecting T_VARIABLE or '$' in /in/1brJs on line 31
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.4.1
Parse error: parse error, unexpected '&', expecting T_VARIABLE or '$' in /in/1brJs on line 31
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/1brJs on line 31
Process exited with code 255.