We use this at https://github.com/puppetlabs/puppet/pull/1848/files#L0R36 as well, and this is a little opaque. It might be a bit more clear to do this:

```ruby
def membership_union(left, right)
  left | right
end

# ...

  new_mem = membership_union(new_mem, @objectinfo.mem)
```

Although I'll admit this is nitpicky, your call on if you would like to do this or not.