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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 be 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);

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