1------------------------------------------------------------------------------ 2-- -- 3-- GNAT LIBRARY COMPONENTS -- 4-- -- 5-- ADA.CONTAINERS.INDEFINITE_HASHED_MAPS -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 2004-2013, 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-- This unit was originally developed by Matthew J Heaney. -- 32------------------------------------------------------------------------------ 33 34with Ada.Iterator_Interfaces; 35 36private with Ada.Containers.Hash_Tables; 37private with Ada.Finalization; 38private with Ada.Streams; 39 40generic 41 type Key_Type (<>) is private; 42 type Element_Type (<>) is private; 43 44 with function Hash (Key : Key_Type) return Hash_Type; 45 with function Equivalent_Keys (Left, Right : Key_Type) return Boolean; 46 with function "=" (Left, Right : Element_Type) return Boolean is <>; 47 48package Ada.Containers.Indefinite_Hashed_Maps is 49 pragma Preelaborate; 50 pragma Remote_Types; 51 52 type Map is tagged private with 53 Constant_Indexing => Constant_Reference, 54 Variable_Indexing => Reference, 55 Default_Iterator => Iterate, 56 Iterator_Element => Element_Type; 57 58 pragma Preelaborable_Initialization (Map); 59 60 type Cursor is private; 61 pragma Preelaborable_Initialization (Cursor); 62 63 Empty_Map : constant Map; 64 -- Map objects declared without an initialization expression are 65 -- initialized to the value Empty_Map. 66 67 No_Element : constant Cursor; 68 -- Cursor objects declared without an initialization expression are 69 -- initialized to the value No_Element. 70 71 function Has_Element (Position : Cursor) return Boolean; 72 -- Equivalent to Position /= No_Element 73 74 package Map_Iterator_Interfaces is new 75 Ada.Iterator_Interfaces (Cursor, Has_Element); 76 77 overriding function "=" (Left, Right : Map) return Boolean; 78 -- For each key/element pair in Left, equality attempts to find the key in 79 -- Right; if a search fails the equality returns False. The search works by 80 -- calling Hash to find the bucket in the Right map that corresponds to the 81 -- Left key. If bucket is non-empty, then equality calls Equivalent_Keys 82 -- to compare the key (in Left) to the key of each node in the bucket (in 83 -- Right); if the keys are equivalent, then the equality test for this 84 -- key/element pair (in Left) completes by calling the element equality 85 -- operator to compare the element (in Left) to the element of the node 86 -- (in Right) whose key matched. 87 88 function Capacity (Container : Map) return Count_Type; 89 -- Returns the current capacity of the map. Capacity is the maximum length 90 -- before which rehashing in guaranteed not to occur. 91 92 procedure Reserve_Capacity (Container : in out Map; Capacity : Count_Type); 93 -- Adjusts the current capacity, by allocating a new buckets array. If the 94 -- requested capacity is less than the current capacity, then the capacity 95 -- is contracted (to a value not less than the current length). If the 96 -- requested capacity is greater than the current capacity, then the 97 -- capacity is expanded (to a value not less than what is requested). In 98 -- either case, the nodes are rehashed from the old buckets array onto the 99 -- new buckets array (Hash is called once for each existing key in order to 100 -- compute the new index), and then the old buckets array is deallocated. 101 102 function Length (Container : Map) return Count_Type; 103 -- Returns the number of items in the map 104 105 function Is_Empty (Container : Map) return Boolean; 106 -- Equivalent to Length (Container) = 0 107 108 procedure Clear (Container : in out Map); 109 -- Removes all of the items from the map 110 111 function Key (Position : Cursor) return Key_Type; 112 -- Returns the key of the node designated by the cursor 113 114 function Element (Position : Cursor) return Element_Type; 115 -- Returns the element of the node designated by the cursor 116 117 procedure Replace_Element 118 (Container : in out Map; 119 Position : Cursor; 120 New_Item : Element_Type); 121 -- Assigns the value New_Item to the element designated by the cursor 122 123 procedure Query_Element 124 (Position : Cursor; 125 Process : not null access procedure (Key : Key_Type; 126 Element : Element_Type)); 127 -- Calls Process with the key and element (both having only a constant 128 -- view) of the node designed by the cursor. 129 130 procedure Update_Element 131 (Container : in out Map; 132 Position : Cursor; 133 Process : not null access procedure (Key : Key_Type; 134 Element : in out Element_Type)); 135 -- Calls Process with the key (with only a constant view) and element (with 136 -- a variable view) of the node designed by the cursor. 137 138 type Constant_Reference_Type 139 (Element : not null access constant Element_Type) is private 140 with 141 Implicit_Dereference => Element; 142 143 type Reference_Type (Element : not null access Element_Type) is private 144 with 145 Implicit_Dereference => Element; 146 147 function Constant_Reference 148 (Container : aliased Map; 149 Position : Cursor) return Constant_Reference_Type; 150 pragma Inline (Constant_Reference); 151 152 function Reference 153 (Container : aliased in out Map; 154 Position : Cursor) return Reference_Type; 155 pragma Inline (Reference); 156 157 function Constant_Reference 158 (Container : aliased Map; 159 Key : Key_Type) return Constant_Reference_Type; 160 pragma Inline (Constant_Reference); 161 162 function Reference 163 (Container : aliased in out Map; 164 Key : Key_Type) return Reference_Type; 165 pragma Inline (Reference); 166 167 procedure Assign (Target : in out Map; Source : Map); 168 169 function Copy (Source : Map; Capacity : Count_Type := 0) return Map; 170 171 procedure Move (Target : in out Map; Source : in out Map); 172 -- Clears Target (if it's not empty), and then moves (not copies) the 173 -- buckets array and nodes from Source to Target. 174 175 procedure Insert 176 (Container : in out Map; 177 Key : Key_Type; 178 New_Item : Element_Type; 179 Position : out Cursor; 180 Inserted : out Boolean); 181 -- Conditionally inserts New_Item into the map. If Key is already in the 182 -- map, then Inserted returns False and Position designates the node 183 -- containing the existing key/element pair (neither of which is modified). 184 -- If Key is not already in the map, the Inserted returns True and Position 185 -- designates the newly-inserted node container Key and New_Item. The 186 -- search for the key works as follows. Hash is called to determine Key's 187 -- bucket; if the bucket is non-empty, then Equivalent_Keys is called to 188 -- compare Key to each node in that bucket. If the bucket is empty, or 189 -- there were no matching keys in the bucket, the search "fails" and the 190 -- key/item pair is inserted in the map (and Inserted returns True); 191 -- otherwise, the search "succeeds" (and Inserted returns False). 192 193 procedure Insert 194 (Container : in out Map; 195 Key : Key_Type; 196 New_Item : Element_Type); 197 -- Attempts to insert Key into the map, performing the usual search (which 198 -- involves calling both Hash and Equivalent_Keys); if the search succeeds 199 -- (because Key is already in the map), then it raises Constraint_Error. 200 -- (This version of Insert is similar to Replace, but having the opposite 201 -- exception behavior. It is intended for use when you want to assert that 202 -- Key is not already in the map.) 203 204 procedure Include 205 (Container : in out Map; 206 Key : Key_Type; 207 New_Item : Element_Type); 208 -- Attempts to insert Key into the map. If Key is already in the map, then 209 -- both the existing key and element are assigned the values of Key and 210 -- New_Item, respectively. (This version of Insert only raises an exception 211 -- if cursor tampering occurs. It is intended for use when you want to 212 -- insert the key/element pair in the map, and you don't care whether Key 213 -- is already present.) 214 215 procedure Replace 216 (Container : in out Map; 217 Key : Key_Type; 218 New_Item : Element_Type); 219 -- Searches for Key in the map; if the search fails (because Key was not in 220 -- the map), then it raises Constraint_Error. Otherwise, both the existing 221 -- key and element are assigned the values of Key and New_Item rsp. (This 222 -- is similar to Insert, but with the opposite exception behavior. It is 223 -- intended for use when you want to assert that Key is already in the 224 -- map.) 225 226 procedure Exclude (Container : in out Map; Key : Key_Type); 227 -- Searches for Key in the map, and if found, removes its node from the map 228 -- and then deallocates it. The search works as follows. The operation 229 -- calls Hash to determine the key's bucket; if the bucket is not empty, it 230 -- calls Equivalent_Keys to compare Key to each key in the bucket. (This is 231 -- the deletion analog of Include. It is intended for use when you want to 232 -- remove the item from the map, but don't care whether the key is already 233 -- in the map.) 234 235 procedure Delete (Container : in out Map; Key : Key_Type); 236 -- Searches for Key in the map (which involves calling both Hash and 237 -- Equivalent_Keys). If the search fails, then the operation raises 238 -- Constraint_Error. Otherwise it removes the node from the map and then 239 -- deallocates it. (This is the deletion analog of non-conditional 240 -- Insert. It is intended for use when you want to assert that the item is 241 -- already in the map.) 242 243 procedure Delete (Container : in out Map; Position : in out Cursor); 244 -- Removes the node designated by Position from the map, and then 245 -- deallocates the node. The operation calls Hash to determine the bucket, 246 -- and then compares Position to each node in the bucket until there's a 247 -- match (it does not call Equivalent_Keys). 248 249 function First (Container : Map) return Cursor; 250 -- Returns a cursor that designates the first non-empty bucket, by 251 -- searching from the beginning of the buckets array. 252 253 function Next (Position : Cursor) return Cursor; 254 -- Returns a cursor that designates the node that follows the current one 255 -- designated by Position. If Position designates the last node in its 256 -- bucket, the operation calls Hash to compute the index of this bucket, 257 -- and searches the buckets array for the first non-empty bucket, starting 258 -- from that index; otherwise, it simply follows the link to the next node 259 -- in the same bucket. 260 261 procedure Next (Position : in out Cursor); 262 -- Equivalent to Position := Next (Position) 263 264 function Find (Container : Map; Key : Key_Type) return Cursor; 265 -- Searches for Key in the map. Find calls Hash to determine the key's 266 -- bucket; if the bucket is not empty, it calls Equivalent_Keys to compare 267 -- Key to each key in the bucket. If the search succeeds, Find returns a 268 -- cursor designating the matching node; otherwise, it returns No_Element. 269 270 function Contains (Container : Map; Key : Key_Type) return Boolean; 271 -- Equivalent to Find (Container, Key) /= No_Element 272 273 function Element (Container : Map; Key : Key_Type) return Element_Type; 274 -- Equivalent to Element (Find (Container, Key)) 275 276 function Equivalent_Keys (Left, Right : Cursor) return Boolean; 277 -- Returns the result of calling Equivalent_Keys with the keys of the nodes 278 -- designated by cursors Left and Right. 279 280 function Equivalent_Keys (Left : Cursor; Right : Key_Type) return Boolean; 281 -- Returns the result of calling Equivalent_Keys with key of the node 282 -- designated by Left and key Right. 283 284 function Equivalent_Keys (Left : Key_Type; Right : Cursor) return Boolean; 285 -- Returns the result of calling Equivalent_Keys with key Left and the node 286 -- designated by Right. 287 288 procedure Iterate 289 (Container : Map; 290 Process : not null access procedure (Position : Cursor)); 291 -- Calls Process for each node in the map 292 293 function Iterate (Container : Map) 294 return Map_Iterator_Interfaces.Forward_Iterator'class; 295 296private 297 pragma Inline ("="); 298 pragma Inline (Length); 299 pragma Inline (Is_Empty); 300 pragma Inline (Clear); 301 pragma Inline (Key); 302 pragma Inline (Element); 303 pragma Inline (Move); 304 pragma Inline (Contains); 305 pragma Inline (Capacity); 306 pragma Inline (Reserve_Capacity); 307 pragma Inline (Has_Element); 308 pragma Inline (Equivalent_Keys); 309 pragma Inline (Next); 310 311 type Node_Type; 312 type Node_Access is access Node_Type; 313 314 type Key_Access is access Key_Type; 315 type Element_Access is access Element_Type; 316 317 type Node_Type is limited record 318 Key : Key_Access; 319 Element : Element_Access; 320 Next : Node_Access; 321 end record; 322 323 package HT_Types is 324 new Hash_Tables.Generic_Hash_Table_Types (Node_Type, Node_Access); 325 326 type Map is new Ada.Finalization.Controlled with record 327 HT : HT_Types.Hash_Table_Type; 328 end record; 329 330 overriding procedure Adjust (Container : in out Map); 331 332 overriding procedure Finalize (Container : in out Map); 333 334 use HT_Types; 335 use Ada.Finalization; 336 use Ada.Streams; 337 338 procedure Write 339 (Stream : not null access Root_Stream_Type'Class; 340 Container : Map); 341 342 for Map'Write use Write; 343 344 procedure Read 345 (Stream : not null access Root_Stream_Type'Class; 346 Container : out Map); 347 348 for Map'Read use Read; 349 350 type Map_Access is access all Map; 351 for Map_Access'Storage_Size use 0; 352 353 type Cursor is record 354 Container : Map_Access; 355 Node : Node_Access; 356 end record; 357 358 procedure Write 359 (Stream : not null access Root_Stream_Type'Class; 360 Item : Cursor); 361 362 for Cursor'Write use Write; 363 364 procedure Read 365 (Stream : not null access Root_Stream_Type'Class; 366 Item : out Cursor); 367 368 for Cursor'Read use Read; 369 370 type Reference_Control_Type is 371 new Controlled with record 372 Container : Map_Access; 373 end record; 374 375 overriding procedure Adjust (Control : in out Reference_Control_Type); 376 pragma Inline (Adjust); 377 378 overriding procedure Finalize (Control : in out Reference_Control_Type); 379 pragma Inline (Finalize); 380 381 type Constant_Reference_Type 382 (Element : not null access constant Element_Type) is 383 record 384 Control : Reference_Control_Type; 385 end record; 386 387 procedure Write 388 (Stream : not null access Root_Stream_Type'Class; 389 Item : Constant_Reference_Type); 390 391 for Constant_Reference_Type'Write use Write; 392 393 procedure Read 394 (Stream : not null access Root_Stream_Type'Class; 395 Item : out Constant_Reference_Type); 396 397 for Constant_Reference_Type'Read use Read; 398 399 type Reference_Type 400 (Element : not null access Element_Type) is 401 record 402 Control : Reference_Control_Type; 403 end record; 404 405 procedure Write 406 (Stream : not null access Root_Stream_Type'Class; 407 Item : Reference_Type); 408 409 for Reference_Type'Write use Write; 410 411 procedure Read 412 (Stream : not null access Root_Stream_Type'Class; 413 Item : out Reference_Type); 414 415 for Reference_Type'Read use Read; 416 417 Empty_Map : constant Map := (Controlled with HT => (null, 0, 0, 0)); 418 419 No_Element : constant Cursor := (Container => null, Node => null); 420 421 type Iterator is new Limited_Controlled and 422 Map_Iterator_Interfaces.Forward_Iterator with 423 record 424 Container : Map_Access; 425 end record; 426 427 overriding procedure Finalize (Object : in out Iterator); 428 429 overriding function First (Object : Iterator) return Cursor; 430 431 overriding function Next 432 (Object : Iterator; 433 Position : Cursor) return Cursor; 434 435end Ada.Containers.Indefinite_Hashed_Maps; 436