anchor.diff:    if FAdditionalResources <> nil then
     begin
       for r in FAdditionalResources do
  -     if r.url = url then
  -     begin
  -       cs := r as TFhirCodeSystemW;
  -       exit(TFhirCodeSystemProvider.Create(FFactory.link, TFHIRCodeSystemEntry.Create(cs.link)));
  -     end;
  +      if (url <> '') and ((r.url = url) or (r.vurl = url)) then
  +      begin
  +        if not (r is TFhirCodeSystemW) then
  +          raise EFHIRException.Create('Attempt to reference '+url+' as a CodeSystem when it''s a '+r.fhirType);
  +        cs := r as TFhirCodeSystemW;
  +        exit(TFhirCodeSystemProvider.Create(FFactory.link, TFHIRCodeSystemEntry.Create(cs.link)));
  +      end;
     end;
     result := FOnGetCSProvider(self, url, version, params, true);
  -
   
     if not nullok then
       raise ETerminologySetup.create('Unable to provide support for code system '+url);
  
positive.code: var
    r : TFHIRMetadataResourceW;
  begin
    if FAdditionalResources <> nil then
    begin
      for r in FAdditionalResources do
       if r.url = url then
         exit(r.link.link as TFHIRValueSetW);
    end;
    result := FOnGetValueSet(self, url);
  end;
  
negative.code:   r : TFHIRMetadataResourceW;
    cs : TFhirCodeSystemW;
  begin
    if (url = '') then
      exit(nil);
  
    result := nil;
  
    if FAdditionalResources <> nil then
    begin
      for r in FAdditionalResources do
        if (url <> '') and ((r.url = url) or (r.vurl = url)) then
        begin
          if not (r is TFhirCodeSystemW) then
            raise EFHIRException.Create('Attempt to reference '+url+' as a CodeSystem when it''s a '+r.fhirType);
          cs := r as TFhirCodeSystemW;
          if (cs.content = cscmComplete) then
          begin
            exit(TFhirCodeSystemProvider.Create(FFactory.link, TFHIRCodeSystemEntry.Create(cs.link)));
          end;
        end;
    end;
    result := FOnGetCSProvider(self, url, version, params, true);
  
  