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<?php $a1=['0'=>'my key should be a (numeric) string']; $a2=[0=>'my key should be an int']; $a3= new stdClass; $a3->{"0"} = 'my key should also a (numeric) string'; $a3=(array)$a3; foreach($a1 as $key=>$val){echo $val.': ';var_dump($key);} foreach($a2 as $key=>$val){echo $val.': ';var_dump($key);} foreach($a3 as $key=>$val){echo $val.': ';var_dump($key);} var_dump($a1,$a2,$a3);
Output for 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
my key should be a (numeric) string: int(0) my key should be an int: int(0) my key should also a (numeric) string: int(0) array(1) { [0]=> string(35) "my key should be a (numeric) string" } array(1) { [0]=> string(23) "my key should be an int" } array(1) { [0]=> string(37) "my key should also a (numeric) string" }
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33
my key should be a (numeric) string: int(0) my key should be an int: int(0) my key should also a (numeric) string: string(1) "0" array(1) { [0]=> string(35) "my key should be a (numeric) string" } array(1) { [0]=> string(23) "my key should be an int" } array(1) { ["0"]=> string(37) "my key should also a (numeric) string" }

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