Is it better to use require_once('filename.php') or require_once 'filename.php';

Question

Is this just a stylistic difference, or does using require_once(\'filename.php\') vs require_once \'filename.php\' have actual load/efficiency diff

Answer 1

Pear Coding Standards say :

"include_once and require_once are statements, not functions. Parentheses should not surround the subject filename."

Source : http://pear.php.net/manual/en/standards.including.php

Answer 2

What does your heart tell you?

Performance difference, if any: negligible.

Answer 3

include, include_once, require and require_once are not functions, they are statements, that is why you should not use ().

Also, consider this from php.net:

<?php

// won't work
if (include('vars.php') == TRUE) {
    echo 'OK';
}

// works
if ((include 'vars.php') == TRUE) {
    echo 'OK';
}

?>

Answer 4

It's exactly the same thing. It's a matter of style.

The parentheses may get in the way some times. For instance, this example from the manual doesn't do what you expect:

if (include('vars.php') == 'OK') {
    echo 'OK';
}

See example #4.

Answer 5

There is no difference. I don't use the brackets 'cause they are not necessary. require_once is no function.