PORK Object System Programmers' Guide

Ora Lassila
tech. report CMU-RI-TR-95-12, Robotics Institute, Carnegie Mellon University, April, 1995


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Abstract
PORK is an object system which brings a conventional object-oriented language closer to the requirements of frame-based programming. It only provides a very limited set of features (on top of the base object system itself), and aims to achieve seamless integration with conventional programming. PORK is implemented as a portable metalevel extension of the Common Lisp Object System (CLOS). It extends CLOS by adding the following concepts:

* Named objects. These simplify debugging and linked frame model construction. Collections of named objects (called "namespaces") can also be used as a low-level implementation vehicle for knowledge bases.

* References to nonexisting named objects. Programs can manipulate objects that have not yet been created. This greatly simplifies definition of complex linked frame models with circular references.

* Slots with multiple values, and a mechanism for defining an access interface.

* Automatic updating of inverse slots.


Notes
Sponsor: ARPA, NASA
Grant ID: F30602-90-C-0019, F30602-91-C-0014, NCC 2-531
Associated Center(s) / Consortia: Center for Integrated Manfacturing Decision Systems
Associated Lab(s) / Group(s): Intelligent Coordination and Logistics Laboratory
Number of pages: 59

Text Reference
Ora Lassila, "PORK Object System Programmers' Guide," tech. report CMU-RI-TR-95-12, Robotics Institute, Carnegie Mellon University, April, 1995

BibTeX Reference
@techreport{Lassila_1995_371,
   author = "Ora Lassila",
   title = "PORK Object System Programmers' Guide",
   booktitle = "",
   institution = "Robotics Institute",
   month = "April",
   year = "1995",
   number= "CMU-RI-TR-95-12",
   address= "Pittsburgh, PA",
}