How should I handle branching to a distinct task whilst the first remains incomplete?
As a specific example, I have a web application where I am able to create appointments on my schedule. These appointments are with another 'person'/'contact'.
While adding an appointment, the user may realise that the person with whom the appointment is to be made is not currently a contact (thus the appointment with another 'person' cannot be made).
How should I handle adding this other 'person' to my contacts without forcing the user to abandon the partially-created appointment?