type

  nsICollection = interface(nsISerializable)
  ['{83b6019c-cbc4-11d2-8cca-0060b0fc14a3}']
    function Count() : PRUint32; safecall;
    function GetElementAt(index: PRUint32) : nsISupports; safecall;
    procedure QueryElementAt(index: PRUint32; constref uuid: TGuid; out result); safecall;
    procedure SetElementAt(index: PRUint32; item: nsISupports); safecall;
    procedure AppendElement(item: nsISupports); safecall;
    procedure RemoveElement(item: nsISupports); safecall;
    function Enumerate() : nsIEnumerator; safecall;
    procedure Clear(); safecall;

  end;