---

12.2.6.3 Operations on A/V Lists

The following operations are defined on A/V lists:

x + y

Addition. The A/V pairs from y are added to x, honoring the respective pairs additivity (see additivity). For example:

( User-Name = "foo" ) + ( Password = "bar" )
⇒ ( User-Name = "foo" Password = "bar" )

( User-Name = "foo" Service-Type = Login-User ) + \
 ( Service-Type = Framed-User Password = "bar" )
⇒ ( User-Name = "foo" \
          Service-Type = Framed-User \
          Password = "bar" )

x - y

Subtraction. The result of this operation is an A/V list consisting of pairs from x, which are not found in y.

( User-Name = "foo" Service-Type = Login-User ) - \
( Service-Type = Framed-User )
⇒ ( User-Name = "foo" )

Notice, that only attribute name matters, its value is ignored.

x % y

Intersection. The result of this operation is an A/V pair list consisting of pairs from x which are also present in y.

( User-Name = "foo" Service-Type = Login-User ) - \
( Service-Type = Framed-User )
⇒ ( Service-Type = Login-User )