The Coding Blacklist. No 52: PHP array_search

PHP has a few “gotchas” which have bitten me in the past. I just got bitten again, today!

I used this PHP code:

$foods = Array();
$foods[] = 'ice cream';
$foods[] = 'hamburger';
$foods[] = 'brussels sprouts';

function do_important_things() {
	echo 'Important!';
};

if (array_search('ice cream', $foods)) {
	do_important_things();
}

I banged my head against the wall for a few minutes when the do_important_things function never got called. I printed out the $foods array and could see that 'ice cream' was in it. So, array_search should return true, right?

So what was going on? Go figure it out for yourself if you want…. or scroll down to get the quick answer.
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PHP’s array_search returns the key of the first value that was matched in the array. Since 'ice cream' had key zero (first item in the array), was returned. In PHP, evaluates to FALSE when it is used in a boolean sense. Like here. They kind of warn you about that in the array_search documentation, but who looks up the docs every time they use an array function?

I kind of went ‘Doh!’ when this happened, because I’ve had this experience once before. I’d just forgotten it. This is a case where an editor plugin might help, but I don’t know of any good solution, except to be careful when using PHP array functions.