| -- CA11021.A |
| -- |
| -- Grant of Unlimited Rights |
| -- |
| -- Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687, |
| -- F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained |
| -- unlimited rights in the software and documentation contained herein. |
| -- Unlimited rights are defined in DFAR 252.227-7013(a)(19). By making |
| -- this public release, the Government intends to confer upon all |
| -- recipients unlimited rights equal to those held by the Government. |
| -- These rights include rights to use, duplicate, release or disclose the |
| -- released technical data and computer software in whole or in part, in |
| -- any manner and for any purpose whatsoever, and to have or permit others |
| -- to do so. |
| -- |
| -- DISCLAIMER |
| -- |
| -- ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR |
| -- DISCLOSED ARE AS IS. THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED |
| -- WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE |
| -- SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE |
| -- OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A |
| -- PARTICULAR PURPOSE OF SAID MATERIAL. |
| --* |
| -- |
| -- OBJECTIVE: |
| -- Check that body of the generic parent package can depend on one of |
| -- its own private generic children. |
| -- |
| -- TEST DESCRIPTION: |
| -- A scenario is created that demonstrates the potential of adding a |
| -- public generic child during code maintenance without distubing a large |
| -- subsystem. After child is added to the subsystem, a maintainer |
| -- decides to take advantage of the new functionality and rewrites |
| -- the parent's body. |
| -- |
| -- Declare a generic package which declares high level operations for a |
| -- complex number abstraction. Declare a private generic child package |
| -- of this package which defines low level complex operations. In the |
| -- parent body, instantiate the private child. Use the low level |
| -- operation to complete the high level operation. |
| -- |
| -- In the main program, instantiate the parent generic package. |
| -- Check that the operations in both packages perform as expected. |
| -- |
| -- |
| -- CHANGE HISTORY: |
| -- 06 Dec 94 SAIC ACVC 2.0 |
| -- |
| --! |
| |
| generic -- Complex number abstraction. |
| type Int_Type is range <>; |
| |
| package CA11021_0 is |
| |
| -- Simulate a generic complex number support package. Complex numbers |
| -- are treated as coordinates in the Cartesian plane. |
| |
| type Complex_Type is private; |
| |
| Zero : constant Complex_Type; -- Real number (0,0). |
| |
| function Real_Part (Complex_No : Complex_Type) |
| return Int_Type; |
| |
| function Imag_Part (Complex_No : Complex_Type) |
| return Int_Type; |
| |
| function Complex (Real, Imag : Int_Type) |
| return Complex_Type; |
| |
| -- High level operation for complex number. |
| function "*" (Factor : Int_Type; |
| C : Complex_Type) return Complex_Type; |
| |
| -- ... and other complicated ones. |
| |
| private |
| type Complex_Type is record |
| Real : Int_Type; |
| Imag : Int_Type; |
| end record; |
| |
| Zero : constant Complex_Type := (Real => 0, Imag => 0); |
| |
| end CA11021_0; |
| |
| --==================================================================-- |
| |
| -- Private generic child of Complex_Number. |
| |
| private |
| |
| generic |
| |
| -- No parameter. |
| |
| package CA11021_0.CA11021_1 is |
| |
| -- ... Other declarations. |
| |
| -- Low level operation on complex number. |
| function "+" (Left, Right : Complex_Type) |
| return Complex_Type; |
| |
| function "-" (Right : Complex_Type) |
| return Complex_Type; |
| |
| -- ... Various other operations in real application. |
| |
| end CA11021_0.CA11021_1; |
| |
| --==================================================================-- |
| |
| package body CA11021_0.CA11021_1 is |
| |
| function "+" (Left, Right : Complex_Type) |
| return Complex_Type is |
| |
| begin |
| return ( (Left.Real + Right.Real, Left.Imag + Right.Imag) ); |
| end "+"; |
| |
| -------------------------------------------------- |
| |
| function "-" (Right : Complex_Type) return Complex_Type is |
| begin |
| return (-Right.Real, -Right.Imag); |
| end "-"; |
| |
| end CA11021_0.CA11021_1; |
| |
| --==================================================================-- |
| |
| with CA11021_0.CA11021_1; -- Private generic child package. |
| |
| package body CA11021_0 is |
| |
| ----------------------------------------------------- |
| -- Parent's body depends on private generic child. -- |
| ----------------------------------------------------- |
| |
| -- Instantiate the private child. |
| |
| package Complex_Ops is new CA11021_1; |
| use Complex_Ops; -- All user-defined operators |
| -- directly visible. |
| |
| -------------------------------------------------- |
| |
| function "*" (Factor : Int_Type; |
| C : Complex_Type) return Complex_Type is |
| Result : Complex_Type := Zero; |
| |
| begin |
| for I in 1 .. abs (Factor) loop |
| Result := Result + C; -- Private generic child "+". |
| end loop; |
| |
| if Factor < 0 then |
| Result := - Result; -- Private generic child "-". |
| end if; |
| |
| return Result; |
| end "*"; |
| |
| -------------------------------------------------- |
| |
| function Real_Part (Complex_No : Complex_Type) return Int_Type is |
| begin |
| return (Complex_No.Real); |
| end Real_Part; |
| |
| -------------------------------------------------- |
| |
| function Imag_Part (Complex_No : Complex_Type) return Int_Type is |
| begin |
| return (Complex_No.Imag); |
| end Imag_Part; |
| |
| -------------------------------------------------- |
| |
| function Complex (Real, Imag : Int_Type) return Complex_Type is |
| begin |
| return (Real, Imag); |
| end Complex; |
| |
| end CA11021_0; |
| |
| --==================================================================-- |
| |
| with CA11021_0; -- Complex number abstraction. |
| |
| with Report; |
| |
| procedure CA11021 is |
| |
| type My_Integer is range -100 .. 100; |
| |
| -------------------------------------------------- |
| |
| -- Declare instance of the generic complex package for one particular |
| -- integer type. |
| |
| package My_Complex_Pkg is new |
| CA11021_0 (Int_Type => My_Integer); |
| |
| use My_Complex_Pkg; -- All user-defined operators |
| -- directly visible. |
| |
| -------------------------------------------------- |
| |
| Complex_One, Complex_Two : Complex_Type; |
| |
| My_Literal : My_Integer := -3; |
| |
| begin |
| |
| Report.Test ("CA11021", "Check that body of the generic parent package " & |
| "can depend on its private generic child"); |
| |
| Complex_One := Complex (11, 6); |
| |
| Complex_Two := 5 * Complex_One; |
| |
| if Real_Part (Complex_Two) /= 55 |
| and Imag_Part (Complex_Two) /= 30 |
| then |
| Report.Failed ("Incorrect results from complex operation"); |
| end if; |
| |
| Complex_One := Complex (-4, 7); |
| |
| Complex_Two := My_Literal * Complex_One; |
| |
| if Real_Part (Complex_Two) /= 12 |
| and Imag_Part (Complex_Two) /= -21 |
| then |
| Report.Failed ("Incorrect results from complex operation"); |
| end if; |
| |
| Report.Result; |
| |
| end CA11021; |
