Specifies whether duplicate strings can be added to sorted lists. Set Duplicates to specify what should happen when an attempt is made to add a duplicate string to a sorted list.
Set Duplicates before adding any strings to the list. Setting Duplicates to dupIgnore or dupError does nothing about duplicate strings that are already in the list.
The value of Duplicates should be one of the following:
Ignore attempts to add duplicate strings to the sorted list.
Raise an EStringListError exception when an attempt is made to add duplicate strings to the sorted list.
Permit duplicate strings in the sorted list.
Duplicates does nothing if the list is not sorted.