define_method(+Obj, +Message, +Body)
Installs Body as the method for Message
in the instance Obj. Following the execution of this goal,
sending Message to Obj will execute Body, rather than the
default method or a method previously defined with
Message must have been declared to be an instance method for the class of Obj.
any argument is unbound.
Obj is not a compound term, or Message or Body is not callable.
Message does not specify an instance method for the class of Obj, or Body include a goal to fetch or store a non-existent slot.