Hi,

I've got an array of user logins and need to provide a way to select
one or more of them with auto-completion. Currently I've got code
straight from readline example:

users = ask("Select users: ", user_logins) do |q|
    q.readline = true
end

The problem is that it says "You must choose one of...." if I select
more than one login. How to allow to select multiple choices?