This operator may only be used in the following ways:
The expression ``record * symbol'' yields the
record which only contains the attribute of record whose name is symbol.
The expression ``record1 * record2'' yields the
The expression ``record1 + record2'' yields a
record wich consists of all attributes of record1 and record2. If
record1 and record2 have a common attribute names, the
corresponding attributes in the result record will have the attribute values
from record1, in contrast to the operator ``+''.
record which containsonly contains the attribute of record whose name is symbol.
The expression ``record * list'', where list is a list of symbols, yields the record which only contains the
attributes of record whose names are in list.
The expression ``list1 * list2'' yields the
``intersection'' of the lists interpreted as multi-sets; if an element is
times contained in list1
and times contained in list2, it will be min(, ) times
contained in the result.
The expression ``number1 * number2'' yields the
product of number1 and number2.