| -- CC50001.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, in an instance, each implicit declaration of a predefined |
| -- operator of a formal tagged private type declares a view of the |
| -- corresponding predefined operator of the actual type (even if the |
| -- operator has been overridden for the actual type). Check that the |
| -- body executed is determined by the type and tag of the operands. |
| -- |
| -- TEST DESCRIPTION: |
| -- The formal tagged private type has an unknown discriminant part, and |
| -- is thus indefinite. This allows both definite and indefinite types |
| -- to be passed as actuals. For tagged types, definite implies |
| -- nondiscriminated, and indefinite implies discriminated (with known |
| -- or unknown discriminants). |
| -- |
| -- Only nonlimited tagged types are tested, since equality operators |
| -- are not predefined for limited types. |
| -- |
| -- A tagged type is passed as an actual to a generic formal tagged |
| -- private type. The tagged type overrides the predefined equality |
| -- operator. A subprogram within the generic calls the equality operator |
| -- of the formal type. In an instance, the equality operator denotes |
| -- a view of the predefined operator of the actual type, but the |
| -- call dispatches to the body of the overriding operator. |
| -- |
| -- |
| -- CHANGE HISTORY: |
| -- 06 Dec 94 SAIC ACVC 2.0 |
| -- 21 Nov 95 SAIC ACVC 2.0.1 fixes: Corrected expected result on |
| -- calls to "=" within the instance. Modified |
| -- commentary. |
| -- |
| --! |
| |
| package CC50001_0 is |
| |
| type Count_Type is tagged record -- Nondiscriminated |
| Count : Integer := 0; -- tagged type. |
| end record; |
| |
| function "="(Left, Right : Count_Type) -- User-defined |
| return Boolean; -- equality operator. |
| |
| |
| subtype Str_Len is Natural range 0 .. 100; |
| subtype Stu_ID is String (1 .. 5); |
| subtype Dept_ID is String (1 .. 4); |
| subtype Emp_ID is String (1 .. 9); |
| type Status is (Student, Faculty, Staff); |
| |
| type Person_Type (Stat : Status; -- Discriminated |
| NameLen, AddrLen : Str_Len) is -- tagged type. |
| tagged record |
| Name : String (1 .. NameLen); |
| Address : String (1 .. AddrLen); |
| case Stat is |
| when Student => |
| Student_ID : Stu_ID; |
| when Faculty => |
| Department : Dept_ID; |
| when Staff => |
| Employee_ID : Emp_ID; |
| end case; |
| end record; |
| |
| function "="(Left, Right : Person_Type) -- User-defined |
| return Boolean; -- equality operator. |
| |
| |
| -- Testing entities: ------------------------------------------------ |
| |
| TC_Count_Item : constant Count_Type := (Count => 111); |
| |
| TC_Person_Item : constant Person_Type := |
| (Faculty, 18, 17, "Eccles, John Scott", "Popham House, Lee", "0931"); |
| |
| --------------------------------------------------------------------- |
| |
| |
| end CC50001_0; |
| |
| |
| --===================================================================-- |
| |
| |
| package body CC50001_0 is |
| |
| function "="(Left, Right : Count_Type) return Boolean is |
| begin |
| return False; -- Return FALSE even if Left = Right. |
| end "="; |
| |
| |
| function "="(Left, Right : Person_Type) return Boolean is |
| begin |
| return False; -- Return FALSE even if Left = Right. |
| end "="; |
| |
| end CC50001_0; |
| |
| |
| --===================================================================-- |
| |
| |
| with CC50001_0; -- Tagged (actual) type declarations. |
| generic -- Generic stack abstraction. |
| |
| type Item (<>) is tagged private; -- Formal tagged private type. |
| |
| package CC50001_1 is |
| |
| -- Simulate a generic stack abstraction. In a real application, the |
| -- second operand of Push might be of type Stack, and type Stack |
| -- would have at least one component (pointing to the top stack item). |
| |
| type Stack is private; |
| |
| procedure Push (I : in Item; TC_Check : out Boolean); |
| |
| -- ... Other stack operations. |
| |
| private |
| |
| -- ... Stack and ancillary type declarations. |
| |
| type Stack is record -- Artificial. |
| null; |
| end record; |
| |
| end CC50001_1; |
| |
| |
| --===================================================================-- |
| |
| |
| package body CC50001_1 is |
| |
| -- For the sake of brevity, the implementation of Push is completely |
| -- artificial; the goal is to model a call of the equality operator within |
| -- the generic. |
| -- |
| -- A real application might implement Push such that it does not add new |
| -- items to the stack if they are identical to the top item; in that |
| -- case, the equality operator would be called as part of an "if" |
| -- condition. |
| |
| procedure Push (I : in Item; TC_Check : out Boolean) is |
| begin |
| TC_Check := not (I = I); -- Call user-defined "="; should |
| -- return FALSE. Negation of |
| -- result makes TC_Check TRUE. |
| end Push; |
| |
| end CC50001_1; |
| |
| |
| --==================================================================-- |
| |
| |
| with CC50001_0; -- Tagged (actual) type declarations. |
| with CC50001_1; -- Generic stack abstraction. |
| |
| use CC50001_0; -- Overloaded "=" directly visible. |
| |
| with Report; |
| procedure CC50001 is |
| |
| package Count_Stacks is new CC50001_1 (CC50001_0.Count_Type); |
| package Person_Stacks is new CC50001_1 (CC50001_0.Person_Type); |
| |
| User_Defined_Op_Called : Boolean; |
| |
| begin |
| Report.Test ("CC50001", "Check that, in an instance, each implicit " & |
| "declaration of a primitive subprogram of a formal tagged " & |
| "private type declares a view of the corresponding " & |
| "predefined operator of the actual type (even if the " & |
| "operator has been overridden or hidden for the actual type)"); |
| |
| -- |
| -- Test which "=" is called inside generic: |
| -- |
| |
| User_Defined_Op_Called := False; |
| |
| Count_Stacks.Push (CC50001_0.TC_Count_Item, |
| User_Defined_Op_Called); |
| |
| |
| if not User_Defined_Op_Called then |
| Report.Failed ("User-defined ""="" not called inside generic for Count"); |
| end if; |
| |
| |
| User_Defined_Op_Called := False; |
| |
| Person_Stacks.Push (CC50001_0.TC_Person_Item, |
| User_Defined_Op_Called); |
| |
| if not User_Defined_Op_Called then |
| Report.Failed ("User-defined ""="" not called inside generic " & |
| "for Person"); |
| end if; |
| |
| |
| -- |
| -- Test which "=" is called outside generic: |
| -- |
| |
| User_Defined_Op_Called := False; |
| |
| User_Defined_Op_Called := |
| not (CC50001_0.TC_Count_Item = CC50001_0.TC_Count_Item); |
| |
| if not User_Defined_Op_Called then |
| Report.Failed ("User-defined ""="" not called outside generic "& |
| "for Count"); |
| end if; |
| |
| |
| User_Defined_Op_Called := False; |
| |
| User_Defined_Op_Called := |
| not (CC50001_0.TC_Person_Item = CC50001_0.TC_Person_Item); |
| |
| if not User_Defined_Op_Called then |
| Report.Failed ("User-defined ""="" not called outside generic "& |
| "for Person"); |
| end if; |
| |
| |
| Report.Result; |
| end CC50001; |
