Why is it that I can't reference a global variable directly in PHP?

Question

I'm curious to know why the following code behaves differently?

The following does not work:

$_variable &= global $_global;
echo $_variable;

The following works:

global $global;
$_variable &= $_global;
echo $_variable;

?

Answer 1

global is a special language construct, it can't be used in operations as you do in example 1.

Answer 2

The global keyword is used to say, "Use the global variable by this name, rather than a local one." The most common use is like this:

$name = 'Slokun';

printName();
function printName() {
    global $name; // Use the global, rather than function-local, version
    echo $name;
}

which would print

Slokun

Compare to:

$name = 'Slokun';
printName();

function printName() {
    echo $name;
}

which wouldn't print anything

Answer 3

Think of the global keyword more like a verb than an adjective. Your first example says "reference assign the global known as $_global to $_variable". But global is not an adjective. The second example, which is correct, says to php, "Treat $_global as a global", or "global-ify $_global", and then make the assignment.