sub myfunc
{
  my ($ref) = @_;
  # modify $ref somehow
  warn "Should be called in void context" if defined wantarray;
}

##</code><code>##

func1();
myfunc($data);
func2();

##</code><code>##

func1(myfunc($data));

##</code><code>##

sub anotherfunc {
  # .. code here
  myfunc($data)
}

func1(anotherfunc())


##</code><code>##

sub xxx : Local Args(0) {
    my ($self, $c, $s, $r, $p) = @_;

    $c->res->body( wantarray );
}