with Ada.Text_IO;
with Ada.Text_IO.Unbounded_IO;
with Ada.Strings.Unbounded;      use Ada.Strings.Unbounded;
with Ada.Containers.Vectors;     use Ada.Containers;
 
procedure Quotes is
   package IO renames Ada.Text_IO;
   package SUIO renames Ada.Text_IO.Unbounded_IO;
   package Quote_Container is new Vectors (Natural, Unbounded_String);
   use Quote_Container;
   Quotes    : Vector;
   Q_Cursor  : Cursor;
   Input     : IO.File_Type;
begin
   IO.Open (File => Input,
            Mode => IO.In_File,
            Name => "quotes.txt");
   while not IO.End_Of_File (File => Input) loop
      Quotes.Append (New_Item => SUIO.Get_Line (File => Input));
   end loop;
   IO.Close (Input);
 
   --  This is bad. If we change the Index_Type from Natural to Positive,
   --  0 would no longer be the first position in the vector.
   Q_Cursor := Quotes.To_Cursor (Index => 0);
   SUIO.Put_Line (Item => Element (Position => Q_Cursor));
 
   --  This is good. We always get the first position, no matter what 
   --  Index_Type we're using.
   Q_Cursor := Quotes.First;
   SUIO.Put_Line (Item => Element (Position => Q_Cursor));
end Quotes;

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