1------------------------------------------------------------------------------ 2-- -- 3-- GNAT LIBRARY COMPONENTS -- 4-- -- 5-- ADA.CONTAINERS.FORMAL_DOUBLY_LINKED_LISTS -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 2004-2012, Free Software Foundation, Inc. -- 10-- -- 11-- This specification is derived from the Ada Reference Manual for use with -- 12-- GNAT. The copyright notice above, and the license provisions that follow -- 13-- apply solely to the contents of the part following the private keyword. -- 14-- -- 15-- GNAT is free software; you can redistribute it and/or modify it under -- 16-- terms of the GNU General Public License as published by the Free Soft- -- 17-- ware Foundation; either version 3, or (at your option) any later ver- -- 18-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 19-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 20-- or FITNESS FOR A PARTICULAR PURPOSE. -- 21-- -- 22-- As a special exception under Section 7 of GPL version 3, you are granted -- 23-- additional permissions described in the GCC Runtime Library Exception, -- 24-- version 3.1, as published by the Free Software Foundation. -- 25-- -- 26-- You should have received a copy of the GNU General Public License and -- 27-- a copy of the GCC Runtime Library Exception along with this program; -- 28-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 29-- <http://www.gnu.org/licenses/>. -- 30------------------------------------------------------------------------------ 31 32-- This spec is derived from Ada.Containers.Bounded_Doubly_Linked_Lists in the 33-- Ada 2012 RM. The modifications are to facilitate formal proofs by making it 34-- easier to express properties. 35 36-- The modifications are: 37 38-- A parameter for the container is added to every function reading the 39-- contents of a container: Next, Previous, Query_Element, Has_Element, 40-- Iterate, Reverse_Iterate, Element. This change is motivated by the need 41-- to have cursors which are valid on different containers (typically a 42-- container C and its previous version C'Old) for expressing properties, 43-- which is not possible if cursors encapsulate an access to the underlying 44-- container. 45 46-- There are three new functions: 47 48-- function Strict_Equal (Left, Right : List) return Boolean; 49-- function Left (Container : List; Position : Cursor) return List; 50-- function Right (Container : List; Position : Cursor) return List; 51 52-- See detailed specifications for these subprograms 53 54private with Ada.Streams; 55with Ada.Containers; 56with Ada.Iterator_Interfaces; 57 58generic 59 type Element_Type is private; 60 61 with function "=" (Left, Right : Element_Type) 62 return Boolean is <>; 63 64package Ada.Containers.Formal_Doubly_Linked_Lists is 65 pragma Pure; 66 67 type List (Capacity : Count_Type) is tagged private with 68 Constant_Indexing => Constant_Reference, 69 Default_Iterator => Iterate, 70 Iterator_Element => Element_Type; 71 -- pragma Preelaborable_Initialization (List); 72 73 type Cursor is private; 74 pragma Preelaborable_Initialization (Cursor); 75 76 Empty_List : constant List; 77 78 No_Element : constant Cursor; 79 80 function Not_No_Element (Position : Cursor) return Boolean; 81 82 package List_Iterator_Interfaces is new 83 Ada.Iterator_Interfaces (Cursor => Cursor, Has_Element => Not_No_Element); 84 85 function Iterate (Container : List; Start : Cursor) 86 return List_Iterator_Interfaces.Reversible_Iterator'Class; 87 88 function Iterate (Container : List) 89 return List_Iterator_Interfaces.Reversible_Iterator'Class; 90 91 function "=" (Left, Right : List) return Boolean; 92 93 function Length (Container : List) return Count_Type; 94 95 function Is_Empty (Container : List) return Boolean; 96 97 procedure Clear (Container : in out List); 98 99 procedure Assign (Target : in out List; Source : List); 100 101 function Copy (Source : List; Capacity : Count_Type := 0) return List; 102 103 function Element (Container : List; Position : Cursor) return Element_Type; 104 105 procedure Replace_Element 106 (Container : in out List; 107 Position : Cursor; 108 New_Item : Element_Type); 109 110 procedure Query_Element 111 (Container : List; Position : Cursor; 112 Process : not null access procedure (Element : Element_Type)); 113 114 procedure Update_Element 115 (Container : in out List; 116 Position : Cursor; 117 Process : not null access procedure (Element : in out Element_Type)); 118 119 procedure Move (Target : in out List; Source : in out List); 120 121 procedure Insert 122 (Container : in out List; 123 Before : Cursor; 124 New_Item : Element_Type; 125 Count : Count_Type := 1); 126 127 procedure Insert 128 (Container : in out List; 129 Before : Cursor; 130 New_Item : Element_Type; 131 Position : out Cursor; 132 Count : Count_Type := 1); 133 134 procedure Insert 135 (Container : in out List; 136 Before : Cursor; 137 Position : out Cursor; 138 Count : Count_Type := 1); 139 140 procedure Prepend 141 (Container : in out List; 142 New_Item : Element_Type; 143 Count : Count_Type := 1); 144 145 procedure Append 146 (Container : in out List; 147 New_Item : Element_Type; 148 Count : Count_Type := 1); 149 150 procedure Delete 151 (Container : in out List; 152 Position : in out Cursor; 153 Count : Count_Type := 1); 154 155 procedure Delete_First 156 (Container : in out List; 157 Count : Count_Type := 1); 158 159 procedure Delete_Last 160 (Container : in out List; 161 Count : Count_Type := 1); 162 163 procedure Reverse_Elements (Container : in out List); 164 165 procedure Swap 166 (Container : in out List; 167 I, J : Cursor); 168 169 procedure Swap_Links 170 (Container : in out List; 171 I, J : Cursor); 172 173 procedure Splice 174 (Target : in out List; 175 Before : Cursor; 176 Source : in out List); 177 178 procedure Splice 179 (Target : in out List; 180 Before : Cursor; 181 Source : in out List; 182 Position : in out Cursor); 183 184 procedure Splice 185 (Container : in out List; 186 Before : Cursor; 187 Position : Cursor); 188 189 function First (Container : List) return Cursor; 190 191 function First_Element (Container : List) return Element_Type; 192 193 function Last (Container : List) return Cursor; 194 195 function Last_Element (Container : List) return Element_Type; 196 197 function Next (Container : List; Position : Cursor) return Cursor; 198 199 procedure Next (Container : List; Position : in out Cursor); 200 201 function Previous (Container : List; Position : Cursor) return Cursor; 202 203 procedure Previous (Container : List; Position : in out Cursor); 204 205 function Find 206 (Container : List; 207 Item : Element_Type; 208 Position : Cursor := No_Element) return Cursor; 209 210 function Reverse_Find 211 (Container : List; 212 Item : Element_Type; 213 Position : Cursor := No_Element) return Cursor; 214 215 function Contains 216 (Container : List; 217 Item : Element_Type) return Boolean; 218 219 function Has_Element (Container : List; Position : Cursor) return Boolean; 220 221 procedure Iterate 222 (Container : List; 223 Process : 224 not null access procedure (Container : List; Position : Cursor)); 225 226 procedure Reverse_Iterate 227 (Container : List; 228 Process : 229 not null access procedure (Container : List; Position : Cursor)); 230 231 generic 232 with function "<" (Left, Right : Element_Type) return Boolean is <>; 233 package Generic_Sorting is 234 235 function Is_Sorted (Container : List) return Boolean; 236 237 procedure Sort (Container : in out List); 238 239 procedure Merge (Target, Source : in out List); 240 241 end Generic_Sorting; 242 243 type Constant_Reference_Type 244 (Element : not null access constant Element_Type) is private 245 with 246 Implicit_Dereference => Element; 247 248 function Constant_Reference 249 (Container : List; -- SHOULD BE ALIASED ??? 250 Position : Cursor) return Constant_Reference_Type; 251 252 function Strict_Equal (Left, Right : List) return Boolean; 253 -- Strict_Equal returns True if the containers are physically equal, i.e. 254 -- they are structurally equal (function "=" returns True) and that they 255 -- have the same set of cursors. 256 257 function Left (Container : List; Position : Cursor) return List; 258 function Right (Container : List; Position : Cursor) return List; 259 -- Left returns a container containing all elements preceding Position 260 -- (excluded) in Container. Right returns a container containing all 261 -- elements following Position (included) in Container. These two new 262 -- functions can be used to express invariant properties in loops which 263 -- iterate over containers. Left returns the part of the container already 264 -- scanned and Right the part not scanned yet. 265 266private 267 268 type Node_Type is record 269 Prev : Count_Type'Base := -1; 270 Next : Count_Type; 271 Element : aliased Element_Type; 272 end record; 273 274 function "=" (L, R : Node_Type) return Boolean is abstract; 275 276 type Node_Array is array (Count_Type range <>) of Node_Type; 277 function "=" (L, R : Node_Array) return Boolean is abstract; 278 279 type List (Capacity : Count_Type) is tagged record 280 Nodes : Node_Array (1 .. Capacity) := (others => <>); 281 Free : Count_Type'Base := -1; 282 Busy : Natural := 0; 283 Lock : Natural := 0; 284 Length : Count_Type := 0; 285 First : Count_Type := 0; 286 Last : Count_Type := 0; 287 end record; 288 289 use Ada.Streams; 290 291 procedure Read 292 (Stream : not null access Root_Stream_Type'Class; 293 Item : out List); 294 295 for List'Read use Read; 296 297 procedure Write 298 (Stream : not null access Root_Stream_Type'Class; 299 Item : List); 300 301 for List'Write use Write; 302 303 type List_Access is access all List; 304 for List_Access'Storage_Size use 0; 305 306 type Cursor is record 307 Node : Count_Type := 0; 308 end record; 309 310 type Constant_Reference_Type 311 (Element : not null access constant Element_Type) is null record; 312 313 procedure Read 314 (Stream : not null access Root_Stream_Type'Class; 315 Item : out Cursor); 316 317 for Cursor'Read use Read; 318 319 procedure Write 320 (Stream : not null access Root_Stream_Type'Class; 321 Item : Cursor); 322 323 for Cursor'Write use Write; 324 325 Empty_List : constant List := (0, others => <>); 326 327 No_Element : constant Cursor := (Node => 0); 328 329end Ada.Containers.Formal_Doubly_Linked_Lists; 330