ConstraintFactory cf = stream.getCas().getConstraintFactory();
List<Type> types = getTypes(block, stream);
FSMatchConstraint result = null;
for (Type eachType : types) {
BasicTypeConstraint anchorConstraint = new BasicTypeConstraint(cf.createTypeConstraint(),
eachType);
anchorConstraint.add(eachType);
if (result != null) {
result = cf.or(result, anchorConstraint);
} else {
result = anchorConstraint;
}