@Check
public void checkDataTypeUniqueName(DataType entry) {
	Domainmodel domain = (Blog) Domainmodel.eContainer();
	if (domain.getElements().stream()
			.filter(e -> (e instanceof DataType) && e != entry)
			.anyMatch(d -> d.getName().equals(entry.getName()))
		) {
			error(
				"Duplicate names detected: " + entry,
				DomainmodelPackage.Literals.DATATYPE__NAME,
				IssueCodes.DUPLICATE_DATATYPE_NAME,
				""); 
	}
}