c3a0003.a

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-- C3A0003.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 a function in a generic instance can be called using
--      an access-to-subprogram value.
--
-- TEST DESCRIPTION:
--      Declare a numeric type in the visible part of a generic package.
--      Declare an access to function type.  Declare three different sine 
--      functions that can be referred to by the access to function type.  
--
--      In the main program, instantiate the generic.  Call each function 
--      indirectly by dereferencing the access value.
--
--
-- CHANGE HISTORY:
--      06 Dec 94   SAIC    ACVC 2.0
--
--!

generic
   type Real_Num is digits <>;

package C3A0003_0 is
   
   TC_Call_Tag : Natural := 0;

   -- Type accesses to any sine function
   type Sine_Function_Ptr is access function   
      (Angle : in Real_Num) return Real_Num;

   function Sine_Calc_Fast  (Angle : in Real_Num) return Real_Num;         

   function Sine_Calc_Acc   (Angle : in Real_Num) return Real_Num;        

   function Sine_Calc_Table (Angle : in Real_Num) return Real_Num;        

end C3A0003_0;


-----------------------------------------------------------------------------


package body C3A0003_0 is

   function Sine_Calc_Fast (Angle : in Real_Num) return Real_Num is
      Sine_Num : Real_Num := 1.0;
   begin
      TC_Call_Tag := 1;
      return Sine_Num;
   end Sine_Calc_Fast;


   function Sine_Calc_Acc (Angle : in Real_Num) return Real_Num is
      Sine_Num : Real_Num := 0.0;
   begin
      TC_Call_Tag := 2;
      return Sine_Num;
   end Sine_Calc_Acc;


   function Sine_Calc_Table (Angle : in Real_Num) return Real_Num is
      Sine_Num : Real_Num := -1.0;
   begin
      TC_Call_Tag := 3;
      return Sine_Num;
   end Sine_Calc_Table;

end C3A0003_0;

-----------------------------------------------------------------------------

with Report;
with C3A0003_0;

procedure C3A0003 is

   type Real is digits 5;

   Subtype Trig_Float is Real range -1.0 .. 1.0;

   package Trig is new C3A0003_0 (Real_Num => Trig_Float);

   Sine_Access : Trig.Sine_Function_Ptr;
   X, Theta    : Trig_Float := 0.0;

begin

   Report.Test ("C3A0003", "Check that a function in a generic instance can "
                         & "be called using an access-to-subprogram value");

   Sine_Access := Trig.Sine_Calc_Fast'Access;

   -- Invoking Sine function designated by access value
   X := Sine_Access.all(Theta);

   If Trig.TC_Call_Tag /= 1 then
      Report.Failed ("Incorrect Sine_Calc_Fast result");
   end if;

   Sine_Access := Trig.Sine_Calc_Acc'Access;

   -- Invoking Sine function designated by access value
   X := Sine_Access.all(Theta);

   If Trig.TC_Call_Tag /= 2 then
      Report.Failed ("Incorrect Sine_Calc_Acc result");
   end if;

   Sine_Access := Trig.Sine_Calc_Table'Access;

   -- Invoking Sine function designated by access value
   X := Sine_Access.all(Theta);

   If Trig.TC_Call_Tag /= 3 then
      Report.Failed ("Incorrect Sine_Calc_Table result");
   end if;

   Report.Result;

end C3A0003;