Re: Redundant isset() check?
| From: | Christoph Becker | Date: | Tue, 04 Nov 2014 12:37:12 +0000 |
| Subject: | Re: Redundant isset() check? | ||
| References: | 1 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-324034@lists.php.net to get a copy of this message | ||
Dotan Cohen wrote:
> Consider the situation where an application will use a different set
> of PDO connection details depending on which version of the site is
> running: production, dev, qa, cron job, etc. Considering that
> $_SERVER['DOCUMENT_ROOT'] may not be set, is this check sufficient:
>
> if ( !isset( !isset($connection_details[$_SERVER['DOCUMENT_ROOT']]) ) {
>
> Or would it be preferable to first check that
> $_SERVER['DOCUMENT_ROOT'] is set before relying on it:
>
> if ( !isset($_SERVER['DOCUMENT_ROOT']) ||
> !isset($connection_details[$_SERVER['DOCUMENT_ROOT']]) ) {
>
> The TRUE case of this if clause will simply use the default connection details:
> $connection_details[0]
Then you might consider using the following:
$index = isset($_SERVER['DOCUMENT_ROOT'])
? $_SERVER['DOCUMENT_ROOT'] : 0;
do_something_with($connection_details[$index]);
BTW: after upgrading to PHP 7 you could use the null coalesce operator[1]:
$index = $_SERVER['DOCUMENT_ROOT'] ?? 0;
[1] <https://wiki.php.net/rfc/isset_ternary>
--
Christoph M. Becker