public int doBefore(ASTNode node,
VariableResolverFactory factory) {
Object object = ((WithNode) node).getNestedStatement().getValue( null,
factory );
DroolsMVELKnowledgeHelper resolver = (DroolsMVELKnowledgeHelper) factory.getVariableResolver( "drools" );
KnowledgeHelper helper = (KnowledgeHelper) resolver.getValue();
helper.modifyRetract( object );
return 0;
}