1.2.49. Array_Map() Passes By Value¶

array_map() requires the callback to receive elements by value. Unlike array_walk(), which accepts by value or by reference, depending on the action taken.

PHP 8.0 and more recent emits a Warning

<?php
// Example, courtery of Juliette Reinders Folmer
function trimNewlines(&$line, $key) {
    $line = str_replace(array("\n", "\r" ), '', $line);
}

$original = [
    "text\n\n",
    "text\n\r"
];

$array = $original;
array_walk($array, 'trimNewlines');

var_dump($array);

array_map('trimNewlines', $original, [0, 1]);

?>

See also array_map.

1.2.49.2. Connex PHP features¶

array

map

by-value

by-reference

1.2.49.2.1. Suggestions¶

Make the callback first argument a reference

1.2.49.2.2. Specs¶

Short name	Structures/ArrayMapPassesByValue
Rulesets	All, Analyze, CE, Changed Behavior, CompatibilityPHP80
Exakat since	2.2.0
PHP Version	With PHP 8.0 and older
Severity	Major
Time To Fix	Quick (30 mins)
Precision	Medium
Available in	Entreprise Edition, Community Edition, Exakat Cloud