| -- C3A0001.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 access to subprogram type can be used to select and |
| -- invoke functions with appropriate arguments dynamically. |
| -- |
| -- TEST DESCRIPTION: |
| -- Declare an access to function type in a package specification. |
| -- Declare three different sine functions that can be referred to by |
| -- the access to function type. |
| -- |
| -- In the main program, call each function indirectly by dereferencing |
| -- the access value. |
| -- |
| -- |
| -- CHANGE HISTORY: |
| -- 06 Dec 94 SAIC ACVC 2.0 |
| -- |
| --! |
| |
| package C3A0001_0 is |
| |
| TC_Call_Tag : Natural := 0; |
| |
| -- Type accesses to any sine function |
| type Sine_Function_Ptr is access function |
| (Angle : in Float) return Float; |
| |
| -- Three 'Sine' functions that model an application situation in which |
| -- one function might be chosen when speed is important, another (using |
| -- a different algorithm) might be chosen when accuracy is important, |
| -- and so on. |
| |
| function Sine_Calc_Fast (Angle : in Float) return Float; |
| |
| function Sine_Calc_Acc (Angle : in Float) return Float; |
| |
| function Sine_Calc_Table (Angle : in Float) return Float; |
| |
| end C3A0001_0; |
| |
| |
| ----------------------------------------------------------------------------- |
| |
| |
| package body C3A0001_0 is |
| |
| function Sine_Calc_Fast (Angle : in Float) return Float is |
| begin |
| TC_Call_Tag := 1; |
| return 1.0; |
| end Sine_Calc_Fast; |
| |
| |
| function Sine_Calc_Acc (Angle : in Float) return Float is |
| begin |
| TC_Call_Tag := 2; |
| return 0.0; |
| end Sine_Calc_Acc; |
| |
| |
| function Sine_Calc_Table (Angle : in Float) return Float is |
| begin |
| TC_Call_Tag := 3; |
| return -1.0; |
| end Sine_Calc_Table; |
| |
| end C3A0001_0; |
| |
| ----------------------------------------------------------------------------- |
| |
| with Report; |
| with C3A0001_0; |
| |
| procedure C3A0001 is |
| |
| Sine_Access : C3A0001_0.Sine_Function_Ptr; |
| X, Theta : Float := 0.0; |
| |
| begin |
| |
| Report.Test ("C3A0001", "Check that access to subprogram can be " & |
| "used to select and invoke an operation with " & |
| "appropriate arguments dynamically"); |
| |
| Sine_Access := C3A0001_0.Sine_Calc_Fast'Access; |
| |
| -- Invoking Sine function designated by access value |
| X := Sine_Access(Theta); |
| |
| If C3A0001_0.TC_Call_Tag /= 1 then |
| Report.Failed ("Incorrect Sine_Calc_Fast result"); |
| end if; |
| |
| Sine_Access := C3A0001_0.Sine_Calc_Acc'Access; |
| |
| -- Invoking Sine function designated by access value |
| X := Sine_Access(Theta); |
| |
| If C3A0001_0.TC_Call_Tag /= 2 then |
| Report.Failed ("Incorrect Sine_Calc_Acc result"); |
| end if; |
| |
| Sine_Access := C3A0001_0.Sine_Calc_Table'Access; |
| |
| -- Invoking Sine function designated by access value |
| X := Sine_Access(Theta); |
| |
| If C3A0001_0.TC_Call_Tag /= 3 then |
| Report.Failed ("Incorrect Sine_Calc_Table result"); |
| end if; |
| |
| Report.Result; |
| |
| end C3A0001; |