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You have retrieved a reference to an item in the address book, such as a person’s entry, and you want to retrieve that person’s properties, such as first and last names.
The records in the address book database are of type ABRecordRef. Each record could be either a
group or a person. We have not discussed groups yet, so let’s focus on
people. Each person could have various types of information assigned
to him, such as his first name, last name, email address, and so on.
Bear in mind that many of these values are optional, and at the time
of creating a new contact in the address book database, the user can
simply leave out fields such as phone number, middle name, email
address, URL, and so forth.