<?php
class B{
    public function process($x){
        return $x;
    }
}
class C{
    public function generate($x){
        throw new Exception;
    }
}
$b = new B;
$c = new C;
try{
    $b->process($c->generate(0));
}
catch(Exception $e){
    $c->generate(0);
}
?>