Obj is a newly created and initialized object. Descriptor is a term describing the object to create. After memory is allocated and any slot initializations are performed, a create message is sent to the object.
The functor of Descriptor indicates the class to create. The arguments of the create message are the arguments of Descriptor.
Descriptor is unbound.
Descriptor is not a valid
unable to allocate enough memory for object.
You must have a
create/N method for every
arity N you want to be able to use in creating instances of a
class. This includes arity 0. If no such method exists, then a domain
error will be raised.
Given the class definition
:- class point = [public x:integer=1, public y:integer=2]. Self <- create. Self <- create(X, Y) :- Self << x(X), Self << y(Y). :- end_class point.
| ?- create(point, Point1).
point object, with the default slot values for
Point1 to the new object. The command
| ?- create(point(10,15), Point2).
point object with values 10 and 15 for slots
respectively, and binds variable
Point2 to the new object.