sub module_method {
  ...
  my anonymous_inner_function = sub {
    ...
  }
  ...
  $anonymous_inner_function->(@_);
  ...
}

##</code><code>##

sub module_method {
  ...
  sub inner_function {
    ...
  }
  ...
  inner_function(@_);
  ...
}

##</code><code>##

sub module_method {
  ...
  local *inner_function = sub {
    ...
  };

  inner_function(@_);
  ...
}