my $rv = mysub();     ## sub is executed. normal
    my $rv = &mysyb();    ## same as above, but bad style, I think
    my $rv = \&mysub;     ## ref to the subroutine <- this is what we want
    my $rv = \&mysub();   ## ref to the return value of the subroutine
    my $rv = \{ &mysub() }; ## same as above