static function fuse(&$opt1, $opt2) {
        return isset($opt1) ? $opt1 : (isset($opt2) ? $opt2 : null); 
    }
static function fuse(&$opt1, $opt2) {
        return isset($opt1) ? $opt1 : (isset($opt2) ? $opt2 : null); 
    }
static function fuse ( & $ opt1 , $ opt2 ) { return isset ( $ opt1 ) ? $ opt1 : ( isset ( $ opt2 ) ? $ opt2 : null ) ; }
Alternate a value to undefined variable

@param   reference   &$opt1  Variable
@param   mixed       $opt2   Alternative value
@return  mixed
Alternate a value to undefined variable