1-- CC70001.A 2-- 3-- Grant of Unlimited Rights 4-- 5-- Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687, 6-- F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained 7-- unlimited rights in the software and documentation contained herein. 8-- Unlimited rights are defined in DFAR 252.227-7013(a)(19). By making 9-- this public release, the Government intends to confer upon all 10-- recipients unlimited rights equal to those held by the Government. 11-- These rights include rights to use, duplicate, release or disclose the 12-- released technical data and computer software in whole or in part, in 13-- any manner and for any purpose whatsoever, and to have or permit others 14-- to do so. 15-- 16-- DISCLAIMER 17-- 18-- ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR 19-- DISCLOSED ARE AS IS. THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED 20-- WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE 21-- SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE 22-- OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A 23-- PARTICULAR PURPOSE OF SAID MATERIAL. 24--* 25-- 26-- OBJECTIVE: 27-- Check that the template for a generic formal package may be a child 28-- package, and that a child instance which is an instance of the 29-- template may be passed as an actual to the formal package. Check that 30-- the visible part of the generic formal package includes the first list 31-- of basic declarative items of the package specification. 32-- 33-- TEST DESCRIPTION: 34-- Declare a list abstraction in a generic package which manages lists of 35-- elements of any nonlimited type. Declare a generic child package of 36-- this package which defines additional list operations. Declare a 37-- generic subprogram which operates on lists of elements of discrete 38-- types. Provide the generic subprogram with three formal parameters: 39-- (1) a formal discrete type which represents a list element type, (2) 40-- a generic formal package with the parent list generic as template, and 41-- (3) a generic formal package with the child list generic as template. 42-- Use the formal discrete type as the generic formal actual part for the 43-- parent formal package. In the main program, declare an instance of 44-- parent, then declare an instance of the child which is itself a child 45-- the parent's instance. Pass these instances as actuals to the generic 46-- subprogram instance. 47-- 48-- 49-- CHANGE HISTORY: 50-- 06 Dec 94 SAIC ACVC 2.0 51-- 05 Nov 95 SAIC ACVC 2.0.1 fixes: Corrected syntax of formal 52-- package declaration. 53-- 27 Feb 97 PWB.CTA Added an elaboration pragma. 54--! 55 56generic 57 type Element_Type is private; -- List elems may be of any nonlimited type. 58package CC70001_0 is -- List abstraction. 59 60 type List_Type is limited private; 61 62 63 -- Return true if current element is last in the list. 64 function End_Of_List (L : List_Type) return Boolean; 65 66 -- Set "current" pointer to first list element. 67 procedure Reset (L : in out List_Type); 68 69private 70 71 type Node_Type; 72 type Node_Pointer is access Node_Type; 73 74 type Node_Type is record 75 Item : Element_Type; 76 Next : Node_Pointer; 77 end record; 78 79 type List_Type is record 80 First : Node_Pointer; 81 Current : Node_Pointer; 82 Last : Node_Pointer; 83 end record; 84 85end CC70001_0; 86 87 88 --==================================================================-- 89 90 91package body CC70001_0 is 92 93 function End_Of_List (L : List_Type) return Boolean is 94 begin 95 return (L.Current = null); 96 end End_Of_List; 97 98 99 procedure Reset (L : in out List_Type) is 100 begin 101 L.Current := L.First; -- Set "current" pointer to first 102 end Reset; -- list element. 103 104end CC70001_0; 105 106 107 --==================================================================-- 108 109 110-- Child must be generic since parent is generic. A formal parameter for 111-- "element type" can not be provided here, because then the type of list 112-- element assumed by these new operations would be different from that 113-- defined by the list type declared in the parent. 114 115generic 116package CC70001_0.CC70001_1 is -- Additional list operations. 117 118 -- Read from current element and advance "current" pointer. 119 procedure Read_Element (L : in out List_Type; E : out Element_Type); 120 121 -- Write to current element and advance "current" pointer. 122 procedure Write_Element (L : in out List_Type; E : in Element_Type); 123 124 -- Add element to end of list. 125 procedure Add_Element (L : in out List_Type; E : in Element_Type); 126 127end CC70001_0.CC70001_1; 128 129 130 --==================================================================-- 131 132 133package body CC70001_0.CC70001_1 is 134 135 procedure Read_Element (L : in out List_Type; E : out Element_Type) is 136 begin 137 -- ... Error-checking code omitted for brevity. 138 E := L.Current.Item; -- Retrieve current element. 139 L.Current := L.Current.Next; -- Advance "current" pointer. 140 end Read_Element; 141 142 143 procedure Write_Element (L : in out List_Type; E : in Element_Type) is 144 begin 145 -- ... Error-checking code omitted for brevity. 146 L.Current.Item := E; -- Write to current element. 147 L.Current := L.Current.Next; -- Advance "current" pointer. 148 end Write_Element; 149 150 151 procedure Add_Element (L : in out List_Type; E : in Element_Type) is 152 New_Node : Node_Pointer := new Node_Type'(E, null); 153 begin 154 if L.First = null then -- No elements in list, so add new 155 L.First := New_Node; -- element at beginning of list. 156 else 157 L.Last.Next := New_Node; -- Add new element at end of list. 158 end if; 159 L.Last := New_Node; -- Set last-in-list pointer. 160 end Add_Element; 161 162end CC70001_0.CC70001_1; 163 164 165 --==================================================================-- 166 167 168with CC70001_0.CC70001_1; -- Generic list abstraction + additional operations. 169generic 170 171 -- Import the list abstraction defined in CC70001_0, as well as the 172 -- additional operations defined in CC70001_0.CC70001_1. Declare a formal 173 -- discrete type. Restrict this generic procedure to operate only on lists 174 -- of discrete elements by passing the formal discrete type as an actual 175 -- parameter to the formal (parent) package. 176 177 type Elem_Type is (<>); -- Discrete types only. 178 with package List_Mgr is new CC70001_0 (Elem_Type); 179 with package List_Ops is new List_Mgr.CC70001_1 (<>); 180 181procedure CC70001_2 (L : in out List_Mgr.List_Type); 182 183 184 --==================================================================-- 185 186 187procedure CC70001_2 (L : in out List_Mgr.List_Type) is 188begin 189 List_Mgr.Reset (L); 190 while not List_Mgr.End_Of_List (L) loop 191 List_Ops.Write_Element (L, Elem_Type'First); 192 end loop; 193end CC70001_2; 194 195 196 --==================================================================-- 197 198 199package CC70001_3 is 200 201 type Points is range 0 .. 10; 202 203 -- ... Various other types used by the application. 204 205end CC70001_3; 206 207 208-- No body for CC70001_3; 209 210 211 --==================================================================-- 212 213 214-- Declare instances of the generic list packages for the discrete type. 215-- In order to establish that the type passed as an actual to the parent 216-- generic (CC70001_0) is the one utilized by the child generic (CC70001_1), 217-- the instance of the child must itself be declared as a child of the 218-- instance of the parent. Since only library units may have or be children, 219-- both instances must be library units. 220 221with CC70001_0; -- Generic list abstraction. 222with CC70001_3; -- Package containing discrete type declaration. 223pragma Elaborate (CC70001_0); 224package CC70001_4 is new CC70001_0 (CC70001_3.Points); 225 226with CC70001_0.CC70001_1; -- Generic extension to list abstraction. 227with CC70001_4; 228package CC70001_4.CC70001_5 is new CC70001_4.CC70001_1; 229 230 231 --==================================================================-- 232 233 234with CC70001_2; -- Generic "zeroing" op for lists of discrete types. 235with CC70001_3; -- Types for application. 236with CC70001_4.CC70001_5; -- Discrete list abstraction + additional ops. 237 238with Report; 239procedure CC70001 is 240 241 package Lists_Of_Scores renames CC70001_4; 242 package Score_Ops renames CC70001_4.CC70001_5; 243 244 Scores : Lists_Of_Scores.List_Type; -- List of points. 245 246 procedure Reset_All_Scores is new CC70001_2 -- Operation on lists of 247 (Elem_Type => CC70001_3.Points, -- points. 248 List_Mgr => Lists_Of_Scores, 249 List_Ops => Score_Ops); 250 251 252 -- Begin test code declarations: ----------------------- 253 254 type TC_Score_Array is array (1 .. 3) of CC70001_3.Points; 255 256 TC_Initial_Values : constant TC_Score_Array := (2, 4, 6); 257 TC_Final_Values : constant TC_Score_Array := (0, 0, 0); 258 259 TC_Correct_Initial_Values : Boolean := False; 260 TC_Correct_Final_Values : Boolean := False; 261 262 263 procedure TC_Initialize_List (L : in out Lists_of_Scores.List_Type) is 264 begin -- Initial list contains 3 scores 265 for I in TC_Score_Array'Range loop -- with the values 2, 4, and 6. 266 Score_Ops.Add_Element (L, TC_Initial_Values(I)); 267 end loop; 268 end TC_Initialize_List; 269 270 271 procedure TC_Verify_List (L : in out Lists_of_Scores.List_Type; 272 Expected : in TC_Score_Array; 273 OK : out Boolean) is 274 Actual : TC_Score_Array; 275 begin -- Verify that all scores have been 276 Lists_of_Scores.Reset (L); -- set to zero. 277 for I in TC_Score_Array'Range loop 278 Score_Ops.Read_Element (L, Actual(I)); 279 end loop; 280 OK := (Actual = Expected); 281 end TC_Verify_List; 282 283 -- End test code declarations. ------------------------- 284 285 286begin 287 Report.Test ("CC70001", "Check that the template for a generic formal " & 288 "package may be a child package, and that a child instance " & 289 "which is an instance of the template may be passed as an " & 290 "actual to the formal package. Check that the visible part " & 291 "of the generic formal package includes the first list of " & 292 "basic declarative items of the package specification"); 293 294 TC_Initialize_List (Scores); 295 TC_Verify_List (Scores, TC_Initial_Values, TC_Correct_Initial_Values); 296 297 if not TC_Correct_Initial_Values then 298 Report.Failed ("List contains incorrect initial values"); 299 end if; 300 301 Reset_All_Scores (Scores); 302 TC_Verify_List (Scores, TC_Final_Values, TC_Correct_Final_Values); 303 304 if not TC_Correct_Final_Values then 305 Report.Failed ("List contains incorrect final values"); 306 end if; 307 308 Report.Result; 309end CC70001; 310