yannickmoy

  with Ada.Text_IO; use Ada.Text_IO;
  with System.Dim.Float_Mks; use System.Dim.Float_Mks;
  with System.Dim.Float_Mks_IO; use System.Dim.Float_Mks_IO;

    procedure Main is
       subtype Distance is System.Dim.Float_Mks.Length;
       subtype Area is System.Dim.Float_Mks.Area;

       D1 : constant Distance := 10.0*m;

       D2 : constant Distance := 20.0*m;

       -- D3 : constant Distance := D1 * D2;
       -- Does not compile. GNAT returns the following error:
       --   main.adb:13:08: dimensions mismatch in object declaration
       --   main.adb:13:37: expected dimension [L], found [L**2]

       A : constant Area := D1 * D2;
    begin
       -- print: Area A is  2.00000E+02 m**2
       Put ("Area A is ");
       Put (Item => A);
       Put_Line ("");
    end Main;

   procedure Open
     (File : in out File_Type;
      Mode : File_Mode;
      Name : String;
      Form : String := "")
   with
     Pre    => not Is_Open (File),
     Post   =>
      Is_Open (File)
      and then Ada.Text_IO.Mode (File) = Mode
      and then (if Mode /= In_File
                  then (Line_Length (File) = 0
                        and then Page_Length (File) = 0)),
     Global => (In_Out => File_System);

   procedure Put (File : File_Type; Item : Character) with
     Pre    => Is_Open (File) and then Mode (File) /= In_File,
     Post   =>
       Line_Length (File)'Old = Line_Length (File)
       and Page_Length (File)'Old = Page_Length (File),
     Global => (In_Out => File_System);

   procedure Close  (File : in out File_Type) with
     Pre    => Is_Open (File),
     Post   => not Is_Open (File),
     Global => (In_Out => File_System);