About Type

My problem is to define an element whose type could be either string or int or boolean, that is an enumeration of all these type.
Do you have an idea how i could do?
I would be very please if someone could help me!!

This is not possible neither with TSD3 nor with TSD4 as both do not support “union” feature of the XML schema language.
You will have to define a new global type (TSD4) that contains a choice of three elements with different names.