GBBopen 1.5 Reference -- deleted-instance-class

deleted-instance-class

deleted-instance-class

unit-instance => class

[Generic Function]

Purpose
Return the class to be used for a deleted unit instance.

Method signatures

deleted-instance-class (unit-instance standard-unit-instance) => #<standard-class deleted-unit-instance>

Package :gbbopen

Module :gbbopen-core

Arguments and values

unit-instance		The unit instance (or space instance) to be deleted
class		A class or a non-`nil`, non-keyword symbol that names a class (the default method returns the class deleted-unit-instance)

Returns
The class or symbol naming the class to be used as the changed class for the deleted instance.

Description
This generic function is called by delete-instance to determine the class to be used as the changed class for a deleted unit instance. The returned class must be a subclass of deleted-unit-instance, but it must not be a subclass of standard-unit-instance.

Example
Define a class to be used for deleted hyp unit instances and a deleted-instance-class method to use deleted-hyp as the class for deleted hyp (and subclasses of hyp) unit instances:

  > (define-class deleted-hyp (deleted-unit-instance)
      (location
       classification
       supporting-hyps)
  #<standard-class deleted-hyp>
  > (defmethod deleted-instance-class ((hyp hyp))
      (load-time-value (find-class 'deleted-hyp)))
  deleted-instance-class
  >

The GBBopen Project

deleted-instance-class