How to expand typehead?

Question

JavaScript

typehead generates a dropdown list from the data
[{"value":"","name":"","lable":""},{"value":"","name":"","lable":" "}, .... ]
there is a task to add the 4th parameter {"value":"","name":"","lable":"", "agrument":""}
and so that when [item selection|hover |or any custom event ] triggered function callback(agrument) { ... }
how to do it nicely?