note 126981 rejected from function.usort by cmb
| From: | cmb@php.net | Date: | Mon, 11 Apr 2022 10:27:58 +0000 |
| Subject: | note 126981 rejected from function.usort by cmb | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-218145@lists.php.net to get a copy of this message | ||
Note Submitter: mail at bemcalavera dot com
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I'm reporting a strange behavior of usort while trying to sort array (with number index in
string format) by subarray item value (see example):
$example = array(
"1" => array("tit" => "title 1", "val" => 2),
"2" => array("tit" => "title 2", "val" => 10),
"3" => array("tit" => "title 3", "val" => 5)
);
usort( $example, function ($a, $b) {
if ( $a["val"] == $b["val"] ) {
return 0;
}
if ( $a["val"] < $b["val"] ) {
return 1;
}else{
return -1;
}
}
In this case usort will mess up all the values of "val" items (!), and in some cases it
creates a new item (with just the "val" field in the new subarray).