.....
TYPE TypeBaseDocuments IS RECORD (
      id    VARCHAR2( 10 ), 
      inout number,
      ourID number NULL); 
type BaseDocuments IS VARRAY( 2000 ) OF TypeBaseDocuments NOT NULL;
.............

BaseDocList BaseDocuments:=BaseDocuments();
CurrentBaseDoc TypeBaseDocuments;

while (DocId is not null) loop
      begin
        CurrentBaseDoc.id:=BaseDocumNum;
        CurrentBaseDoc.inout:=BaseDocumType;
        BaseDocList:=BaseDocuments(CurrentBaseDoc);
        select basedocindex_, basedockind_ into CurrentBaseDoc.id, CurrentBaseDoc.inout from t_naclhead where ((id_=BaseDocumNum) and (inout_=BaseDocumType));
        BaseDocList:=BaseDocuments(CurrentBaseDoc);
        BaseDocumNum:=CurrentBaseDoc.id;
        BaseDocumType:=CurrentBaseDoc.inout;
        PosBaseDocList:=PosBaseDocList+ 1 ;
      exception when others then
        DocId:=null;
      end; --exception
 
    end loop; --while
 

...
exception when others then
        DocId:=null;
....