Hide Login/Register to vote and to have access to more features

You are here: Root > Standards and Specifications > XML

View the dependency graph for this library

Common Lisp Reasoner
Created by hounslow on: Mon, 14 Apr 2008 18:03:37 GMT, Last modification: Mon, 02 Jul 2012 16:06:18 GMT

Provides tightly-integrated knowledge representation, reasoning and search capabilities, with vanilla XML and RDF/XML interfaces, built around a portable extension of CLOS.

eMail
Web site	http://reasoner.sourceforge.net/
Mailing list
Version	3.0 - Monday, 02 July 2012
Maturity	Stable
OS compatibility	All
ASDF installable	No
Official Download	http://sourceforge.net/projects/reasoner
Mirrored Download
Source code repository

Common Lisp Reasoner

Introduction

The Common Lisp Reasoner project aims to create a practical technology that exploits the synergy between its three major components to make AI-related applications, such as scheduling and diagnosis, easier to develop. These components are:

• A portable extension of the Common Lisp Object System (CLOS)
• The Assumption-Based Truth-Maintenance System (ATMS) of de Kleer
• A rule language comprising non-directional constraints as well as unidirectional rules

Because CLOS permits, by means of the Metaobject Protocol, open-ended extension, it is both the implementation language and the kernel of the implemented system, within which a set of sound principles appropriate to the practice of knowledge representation rather than programming have been realized.

In reasoning applications, the values stored into the slots of an instance (the data to be reasoned with) are accumulated rather than replaced. Permitted values are specified in the class of the instance. They are either other instances, or enumerated ranges of (mutually exclusive) values that may subsequently be narrowed by reasoning activity.

Each stored value is encapsulated in an ATMS nodea record not only of the value, but also its justification (derivation) and the resultant belief states (or environments), determined by the ATMS, in which it holds. An environment is given by a set of primitive assumptions; an assumption constitutes an explicit, problem-specific decision to assume some datum or data. The ATMS enables environments to be explored systematically and efficiently.

The rule language permits the expression of arbitrarily complex logical sentences. The slot definitions of classes collectively constitute a vocabulary of attributes that can be referred to in rule definitions. When reasoning, classes and instances provide an efficient means of retrieving rules and the data upon which they operate.

Source code may be downloaded via the project page. Before downloading, consult the release notes to determine compatibility with your Common Lisp implementation of choice.

Historical Note

The design outlined above was conceived in relation to the development of legal reasoning applications, in order to meet some exacting requirements: to capture the explicit and implicit exceptions inherent in legal language, to accommodate conflicting rules which give rise to competing arguments, and to derive all inferences sanctioned by a logical sentence by restricting the values of attributes.

Compatible Implementations

ECL | Steel Bank Common Lisp | CLISP | Allegro Common Lisp

Tags

XML | Language Extensions | Object-Oriented | Expert Systems

0 Notes and 0 comments