I found a question as following in one of mock papers:
What are correct statements about creating scripting variables for a Tag::
1) It is necessary to implement TagExtraInfo interface. 2) You have to insert into the tag element of the taglib descriptor file an entry for tei-class element. 3) The interface you have to implement has a method called getVariableInfo. 4) None of the previous.
Answer is 1,2,3.Please explain me how and what are scripting variables ?