JarCasting
Graal Defeasible Core
This is the parser module for Defeasible Datalog+-, it can parse strict, defeasible, and defeater (existential) rules along with preferences on rules and on alternatives using DLGP fromat.
Getting Started
You can either import this module using Maven Central (recommended). Add the following to your pom.xml:
<dependency>
<groupId>fr.lirmm.graphik</groupId>
<artifactId>graal-defeasible-core</artifactId>
<version>0.0.2</version>
</dependency>
Or using Github then adding it to your project:
> git clone https://github.com/hamhec/graal-defeasible-core.git
Example
penguin(kowalski). # strict fact.
bird(tweety) <= . # defeasible fact.
brokenWing(tweety) <= . # defeasible fact.
# penguins definetly are birds who do not fly
[r1] notFly(X), bird(X) <- penguin(X). # strict rule, the label [r1] is optional
# birds generally fly
[r2] fly(X) <= bird(X). # defeasible rule
# birds with broken wings are not able to fly
[r3] notFly(X) <~ bird(X), brokenWings(X). # defeater rule
# r3 is preferred to r2
r3 >> r2. # preference on rules.
# one cannot fly and notFly at the same time (it leads to bottom '!' )
! :- fly(X), notFly(X). # Negative Constraint to express negation.
Authors
License
This project is licensed under CeCILL 2.1 - see the LICENSE file for details