Shell Sort

[Shark8 <onewingedshark@gmail.com>]

I'm having some trouble with a Shell Sort I'm writing; I think I
screwed up the internal insertion sort.

Type ARR is Array (Integer Range <>) of Integer;

   Procedure Sort( Input : in out ARR ) is
      Gaps : constant array(Positive Range <>) of Integer:=
           (1, 4, 10, 23, 57, 132, 301, 701, 1750);

      Initial_Gap_Index : Integer;
   begin
      If Input'Length > 1 then

         For Index in reverse Gaps'Range loop
            Initial_Gap_Index:= Index;
            exit when Gaps(Initial_Gap_Index) < Input'Length;
         end loop;

         For GapIndex in reverse Gaps'First..Initial_Gap_Index loop
            declare
               Inc	: Integer:= Gaps(GapIndex);
               Index	: Integer;
               Temp	: Integer;
            begin
               For Gap_Index in Input'First..Input'Last-Inc loop
                  Index:= Gap_Index;
                  Temp:= Input(Index);
                  while Index+Inc in Input'Range loop

                     if Temp >= Input(Index+Inc) then
                        Swap( Input, Index, Index+Inc );
                     end if;
                     Index:= Index + Inc;
                  end loop;
               end loop;
            end;
         end loop;

      end if;
   end Sort;