Variable variable class extensions in PHP--is it possible?

Question

Is something like the following possible in PHP?

$blah = \'foo1\';

class foo2 extends $blah {
    //...
}

class foo1 {
    //...
}

This g

Answer 1

you should have tried $$

$blah = 'foo1';
class foo2 extends $$blah {
    //...
}

class foo1 {
    //...
}