Is it possible to create a TYPE in postgreSQL whose field data types are same as that of existing table.

For example, I have tables
1. tblEMPLOYEE(EMPLOYEE_ID INTEGER, EMPLOYEE_NAME VARCHAR(50))
2. tblDEPT(DEPT_ID INTEGER, DEPT_NAME VARCHAR(50))
3. tblEMPLOYEE_DEPT(EMPLOYEE_ID INTEGER, DEPT_ID INTEGER).

I have created a composite type:
typeEMPLOYEE_DEPT(EMPLOYEE_ID INTEGER, EMPLOYEE_NAME VARCHAR(50), DEPT_NAME VARCHAR(50)) which is the return type from a function.

How can I create a type where the size of varchar in typeEMPLOYEE_DEPT changes whenever I make a change to the size of varchar field DEPT_NAME in table tblDEPT? (by use of something like %type)

Thanks.
roshni