PHP variable scope question

Question

According to the PHP manual $a should be available to b.inc in the following code segment:

<?php
$a = 1;
include 'b.inc';
?>

However when I try to do the same when calling a static method, $a seems to be out of scope.

class foo {
    public static function bar() {
        $a = 1;
        include('b.inc');               
    }
}

foo::bar();

Am I misunderstanding something? EDIT: Okay, I'm an idiot, everybody. I was using a wrapper function for the include -- to fill in the include path. This took the variable out of scope. Thanks for the help.

Answer 1

Inside the class you need to say that you mean the global one.

class foo {
    public static function bar() {
        global $a;
        var_dump($a);
    }
}

foo::bar();

Answer 2

It totally works for me. If you are describing the problem accurately, something must be happening to $a inside of b.inc.

Answer 3

<?php
//a.php
class test
{
    public static function run()
    {
        $a = 'Some value';
        include 'b.php'; //echo $a;
    }
}
test::run();
?>

all works fine in my test aswell.

Answer 4

Function scope is different than the global scope. b.inc will see $a, and any variables created in b.inc will be in foo::bar()'s scope (unless they are defined as globals, or inside their own function scope).

You can test this with some code:

function foo() {
    $a = 1;
    include '1.php'; // modify and initialize, ie. $a++; $b = 3; 
    include '2.php'; // test the values: $a == 2; $b == 3
}

We run into this problem occasionally when we bootstrap WordPress in other scripts: the initialization scripts assume they are in the outermost scope so they will set variables like $wpdb (the database object), but that file will actually get created in some function that did a require_once(). The solution is to always bootstrap WordPress in the app before you get into any function scope.