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<?php $array = array( 55 => array( 'ident' => 'test 1', ), 77 => array( 'parent_id' => 55, 'ident' => 'test 2', ), 109 => array( 'parent_id' => 77, 'ident' => 'test 3', ), 78 => array( 'parent_id' => 55, 'ident' => 'test 4', ), 25 => array( 'ident' => 'test 5', ) ); foreach ($array as $key => &$sub) { if (isset($sub['parent_id'])) { $array[$sub['parent_id']]['children'][$key] = &$sub; } } unset($sub); // unset the reference to make sure to not overwrite it later... // now remove the entries with parents foreach ($array as $key => $sub) { if (isset($sub['parent_id'])) unset($array[$key]); } var_dump($array);
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
array(2) { [55]=> array(2) { ["ident"]=> string(6) "test 1" ["children"]=> array(2) { [77]=> array(3) { ["parent_id"]=> int(55) ["ident"]=> string(6) "test 2" ["children"]=> array(1) { [109]=> array(2) { ["parent_id"]=> int(77) ["ident"]=> string(6) "test 3" } } } [78]=> array(2) { ["parent_id"]=> int(55) ["ident"]=> string(6) "test 4" } } } [25]=> array(1) { ["ident"]=> string(6) "test 5" } }
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 array(2) { [55]=> array(2) { ["ident"]=> string(6) "test 1" ["children"]=> array(2) { [77]=> array(3) { ["parent_id"]=> int(55) ["ident"]=> string(6) "test 2" ["children"]=> array(1) { [109]=> array(2) { ["parent_id"]=> int(77) ["ident"]=> string(6) "test 3" } } } [78]=> array(2) { ["parent_id"]=> int(55) ["ident"]=> string(6) "test 4" } } } [25]=> array(1) { ["ident"]=> string(6) "test 5" } }
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '&', expecting T_VARIABLE or '$' in /in/QfVUr on line 26
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '&', expecting T_VARIABLE or '$' in /in/QfVUr on line 26
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/QfVUr on line 26
Process exited with code 255.

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