Error occured (NullPointerException): 
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.patterns.PConstraintTransformer.hasValueExpression(PConstraintTransformer.java:487)
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.patterns.PConstraintTransformer._transformConstraint(PConstraintTransformer.java:614)
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.patterns.PConstraintTransformer.transformConstraint(PConstraintTransformer.java:689)
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.patterns.RelationDefinitionIndexer.transformPattern(RelationDefinitionIndexer.java:169)
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.patterns.RelationDefinitionIndexer.generateRelationDefinitions(RelationDefinitionIndexer.java:51)
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.patterns.PatternGenerator.transformBaseProperties(PatternGenerator.java:747)
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.patterns.PatternProvider.generateQueries(PatternProvider.java:59)
    hu.bme.mit.inf.dslreasoner.viatrasolver.logic2viatra.ModelGenerationMethodProvider.createModelGenerationMethod(ModelGenerationMethodProvider.java:57)
    hu.bme.mit.inf.dslreasoner.viatrasolver.reasoner.ViatraReasoner.solve(ViatraReasoner.java:96)
    hu.bme.mit.inf.dslreasoner.application.execution.GenerationTaskExecutor.executeGenerationTask(GenerationTaskExecutor.java:316)
    hu.bme.mit.inf.dslreasoner.application.execution.ScriptExecutor._execute(ScriptExecutor.java:129)
    hu.bme.mit.inf.dslreasoner.application.execution.ScriptExecutor.execute(ScriptExecutor.java:338)
    hu.bme.mit.inf.dslreasoner.application.execution.ScriptExecutor.executeScript(ScriptExecutor.java:110)
    hu.bme.mit.inf.dslreasoner.application.execution.StandaloneScriptExecutor.executeScript(StandaloneScriptExecutor.java:149)
    run.FamilyTreeGen.main(FamilyTreeGen.java:7)