Unique value of the item list column

5

Hi,
It often happens that the list of items should have unique values, at least in 1 column.
Currently, I often create and add a script to check when adding an item with this value already exists.
A great convenience would be the option in the column configuration, 'unique item'.
The user would receive an alert that an item with this value has already been added to the list.

Regards.