$self->{&{\&{$testname}}}->($system); #system is hashref

##</code><code>##

Use of uninitialized value $self in concatenation (.) or string
Can't call method "_idown" on an undefined value
Can't call method "_idown" on an undefined value

##</code><code>##

sub method {
    my $self = shift or die join(", ", caller()), "\n";
...
}