The ask* functions in buffer.rb are not commented. As far as I found
out, the arguments are:

domain:      token used as key for @textfields, which seems to be a
             dictionary of input field objects
question:    string used as prompt
completions: array of possible answers, that can be completed by using
             the tab key
default:     default value to return

Is this correct?

Greetings,
Ruthard