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<?php $a=array('title'=>'a','arr'=>[]); $b=array('title'=>'b','arr'=>[]); $b=array('title'=>'c','arr'=>[]); $arr=Array(); $map=Array(); $arr[1]=&$a; $map[0]=&$a; $map[1]=&$b; $map[2]=&$c; $map[0]['arr'][22]=$b; //$map[1]['arr'][33]=$c; ?><h2>MAP</h2><? var_dump($map); ?><h2>ARR</h2><? var_dump($arr);
Output for 7.2.29 - 7.2.33, 7.3.16 - 7.3.31, 7.4.0 - 7.4.32, 8.0.0 - 8.0.12, 8.0.14 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
<h2>MAP</h2><? var_dump($map); ?><h2>ARR</h2><? var_dump($arr);
Output for 5.4.2 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0, 7.3.32 - 7.3.33, 7.4.33, 8.0.13
<h2>MAP</h2>array(3) { [0]=> &array(2) { ["title"]=> string(1) "a" ["arr"]=> array(1) { [22]=> array(2) { ["title"]=> string(1) "c" ["arr"]=> array(0) { } } } } [1]=> &array(2) { ["title"]=> string(1) "c" ["arr"]=> array(0) { } } [2]=> &NULL } <h2>ARR</h2>array(1) { [1]=> &array(2) { ["title"]=> string(1) "a" ["arr"]=> array(1) { [22]=> array(2) { ["title"]=> string(1) "c" ["arr"]=> array(0) { } } } } }

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