note 112196 added to function.array-merge

Please note that -1 is a numeric key and will be reindexed. Less obvious numeric keys are also '-1' (becomes -1) and -1.5 (becomes -1). '-1a', however, is not a numeric key and you could exploit the fact that '-1a' == -1 evaluates to true in php (just a hint). But as this is not very efficient, operator + may be a better option. <?php $arr = array(-1=> "-1", '-2'=> "'-2'", -3.5=> "-3.5", '-4a'=> "'-4a'"); print_r(array( $arr, array_merge($arr,array()), '-1a' == -1, )); ?> Result: Array ( [0] => Array ( [-1] => -1 [-2] => '-2' [-3] => -3.5 [-4a] => '-4a' ) [1] => Array ( [0] => -1 [1] => '-2' [2] => -3.5 [-4a] => '-4a' ) [2] => 1 ) ---- Server IP: 193.9.21.50 Probable Submitter: 77.94.130.234 ---- Manual Page -- http://php.net/manual/en/function.array-merge.php Edit -- https://master.php.net/note/edit/112196 Del: integrated -- https://master.php.net/note/delete/112196/integrated Del: useless -- https://master.php.net/note/delete/112196/useless Del: bad code -- https://master.php.net/note/delete/112196/bad+code Del: spam -- https://master.php.net/note/delete/112196/spam Del: non-english -- https://master.php.net/note/delete/112196/non-english Del: in docs -- https://master.php.net/note/delete/112196/in+docs Del: other reasons-- https://master.php.net/note/delete/112196 Reject -- https://master.php.net/note/reject/112196 Search -- https://master.php.net/manage/user-notes.php