Fun with returning nothing in different languages

nothing.perl

sub Foo {
  return;
}

sub Bar {
  return undef;
}

my $foo_item = Foo();
my $bar_item = Bar();

my $foo_things = [Foo()];
my $bar_things = [Bar()];

nothing.py

def foo():
  return

def bar():
  return None

foo_item = foo()
bar_item = bar()

foo_things = [foo()]
bar_things = [bar()]

nothing.rb

def foo
  return
end

def bar
  return nil
end

foo_item = foo
bar_item = bar

foo_things = [foo]
bar_things = [bar]