final ConnectiveDescr c = (ConnectiveDescr) parser.getCurrent();
Object p = parser.getParent();
if ( p instanceof PatternDescr ) {
StringBuilder sb = new StringBuilder();
c.buildExpression( sb );
ExprConstraintDescr expr = new ExprConstraintDescr();
expr.setExpression( sb.toString() );
final PatternDescr patternDescr = (PatternDescr) parser.getParent();