1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- A S P E C T S -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 2010-2012, Free Software Foundation, Inc. -- 10-- -- 11-- GNAT is free software; you can redistribute it and/or modify it under -- 12-- terms of the GNU General Public License as published by the Free Soft- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. -- 17-- -- 18-- As a special exception under Section 7 of GPL version 3, you are granted -- 19-- additional permissions described in the GCC Runtime Library Exception, -- 20-- version 3.1, as published by the Free Software Foundation. -- 21-- -- 22-- You should have received a copy of the GNU General Public License and -- 23-- a copy of the GCC Runtime Library Exception along with this program; -- 24-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 25-- <http://www.gnu.org/licenses/>. -- 26-- -- 27-- GNAT was originally developed by the GNAT team at New York University. -- 28-- Extensive contributions were provided by Ada Core Technologies Inc. -- 29-- -- 30------------------------------------------------------------------------------ 31 32-- This package defines the aspects that are recognized by GNAT in aspect 33-- specifications. It also contains the subprograms for storing/retrieving 34-- aspect specifications from the tree. The semantic processing for aspect 35-- specifications is found in Sem_Ch13.Analyze_Aspect_Specifications. 36 37------------------------ 38-- Adding New Aspects -- 39------------------------ 40 41-- In general, each aspect should have a corresponding pragma, so that the 42-- newly developed functionality is available for Ada versions < Ada 2012. 43-- When both are defined, it is convenient to first transform the aspect into 44-- an equivalent pragma in Sem_Ch13.Analyze_Aspect_Specifications, and then 45-- analyze the pragma in Sem_Prag.Analyze_Pragma. 46 47-- To add a new aspect, you need to do the following 48 49-- 1. Create a name in snames.ads-tmpl 50 51-- 2. Create a value in type Aspect_Id in this unit 52 53-- 3. Add a value for the aspect in the global arrays defined in this unit 54 55-- 4. Add code for the aspect in Sem_Ch13.Analyze_Aspect_Specifications. 56-- This may involve adding some nodes to the tree to perform additional 57-- treatments later. 58 59-- 5. If the semantic analysis of expressions/names in the aspect should not 60-- occur at the point the aspect is defined, add code in the adequate 61-- semantic analysis procedure for the aspect. For example, this is the 62-- case for aspects Pre and Post on subprograms, which are pre-analyzed 63-- at the end of the declaration list to which the subprogram belongs, 64-- and fully analyzed (possibly with expansion) during the semantic 65-- analysis of subprogram bodies. 66 67with Namet; use Namet; 68with Snames; use Snames; 69with Types; use Types; 70 71package Aspects is 72 73 -- Type defining recognized aspects 74 75 type Aspect_Id is 76 (No_Aspect, -- Dummy entry for no aspect 77 Aspect_Abstract_State, -- GNAT 78 Aspect_Address, 79 Aspect_Alignment, 80 Aspect_Attach_Handler, 81 Aspect_Bit_Order, 82 Aspect_Component_Size, 83 Aspect_Constant_Indexing, 84 Aspect_Contract_Case, -- GNAT 85 Aspect_Contract_Cases, -- GNAT 86 Aspect_Convention, 87 Aspect_CPU, 88 Aspect_Default_Component_Value, 89 Aspect_Default_Iterator, 90 Aspect_Default_Value, 91 Aspect_Dimension, -- GNAT 92 Aspect_Dimension_System, -- GNAT 93 Aspect_Dispatching_Domain, 94 Aspect_Dynamic_Predicate, 95 Aspect_External_Name, 96 Aspect_External_Tag, 97 Aspect_Global, -- GNAT 98 Aspect_Implicit_Dereference, 99 Aspect_Input, 100 Aspect_Interrupt_Priority, 101 Aspect_Invariant, -- GNAT 102 Aspect_Iterator_Element, 103 Aspect_Link_Name, 104 Aspect_Machine_Radix, 105 Aspect_Object_Size, -- GNAT 106 Aspect_Output, 107 Aspect_Post, 108 Aspect_Postcondition, 109 Aspect_Pre, 110 Aspect_Precondition, 111 Aspect_Predicate, -- GNAT 112 Aspect_Priority, 113 Aspect_Read, 114 Aspect_Relative_Deadline, 115 Aspect_Scalar_Storage_Order, -- GNAT 116 Aspect_Simple_Storage_Pool, -- GNAT 117 Aspect_Size, 118 Aspect_Small, 119 Aspect_Static_Predicate, 120 Aspect_Storage_Pool, 121 Aspect_Storage_Size, 122 Aspect_Stream_Size, 123 Aspect_Suppress, 124 Aspect_Synchronization, 125 Aspect_Test_Case, -- GNAT 126 Aspect_Type_Invariant, 127 Aspect_Unsuppress, 128 Aspect_Value_Size, -- GNAT 129 Aspect_Variable_Indexing, 130 Aspect_Warnings, -- GNAT 131 Aspect_Write, 132 133 -- The following aspects correspond to library unit pragmas 134 135 Aspect_All_Calls_Remote, 136 Aspect_Compiler_Unit, -- GNAT 137 Aspect_Elaborate_Body, 138 Aspect_Preelaborate, 139 Aspect_Preelaborate_05, -- GNAT 140 Aspect_Pure, 141 Aspect_Pure_05, -- GNAT 142 Aspect_Pure_12, -- GNAT 143 Aspect_Remote_Call_Interface, 144 Aspect_Remote_Types, 145 Aspect_Shared_Passive, 146 Aspect_Universal_Data, -- GNAT 147 148 -- Remaining aspects have a static boolean value that turns the aspect 149 -- on or off. They all correspond to pragmas, but are only converted to 150 -- the pragmas where the value is True. A value of False normally means 151 -- that the aspect is ignored, except in the case of derived types where 152 -- the aspect value is inherited from the parent, in which case, we do 153 -- not allow False if we inherit a True value from the parent. 154 155 Aspect_Ada_2005, -- GNAT 156 Aspect_Ada_2012, -- GNAT 157 Aspect_Asynchronous, 158 Aspect_Atomic, 159 Aspect_Atomic_Components, 160 Aspect_Discard_Names, 161 Aspect_Export, 162 Aspect_Favor_Top_Level, -- GNAT 163 Aspect_Independent, 164 Aspect_Independent_Components, 165 Aspect_Import, 166 Aspect_Inline, 167 Aspect_Inline_Always, -- GNAT 168 Aspect_Interrupt_Handler, 169 Aspect_No_Return, 170 Aspect_Pack, 171 Aspect_Persistent_BSS, -- GNAT 172 Aspect_Preelaborable_Initialization, 173 Aspect_Pure_Function, -- GNAT 174 Aspect_Remote_Access_Type, -- GNAT 175 Aspect_Shared, -- GNAT (equivalent to Atomic) 176 Aspect_Simple_Storage_Pool_Type, -- GNAT 177 Aspect_Suppress_Debug_Info, -- GNAT 178 Aspect_Unchecked_Union, 179 Aspect_Universal_Aliasing, -- GNAT 180 Aspect_Unmodified, -- GNAT 181 Aspect_Unreferenced, -- GNAT 182 Aspect_Unreferenced_Objects, -- GNAT 183 Aspect_Volatile, 184 Aspect_Volatile_Components, 185 186 -- Aspects that have a static boolean value but don't correspond to 187 -- pragmas 188 189 Aspect_Lock_Free); 190 191 subtype Aspect_Id_Exclude_No_Aspect is 192 Aspect_Id range Aspect_Id'Succ (No_Aspect) .. Aspect_Id'Last; 193 -- Aspect_Id's excluding No_Aspect 194 195 -- The following array indicates aspects that accept 'Class 196 197 Class_Aspect_OK : constant array (Aspect_Id) of Boolean := 198 (Aspect_Invariant => True, 199 Aspect_Pre => True, 200 Aspect_Predicate => True, 201 Aspect_Post => True, 202 Aspect_Type_Invariant => True, 203 others => False); 204 205 -- The following array indicates aspects that a subtype inherits from 206 -- its base type. True means that the subtype inherits the aspect from 207 -- its base type. False means it is not inherited. 208 209 Base_Aspect : constant array (Aspect_Id) of Boolean := 210 (Aspect_Atomic => True, 211 Aspect_Atomic_Components => True, 212 Aspect_Discard_Names => True, 213 Aspect_Independent_Components => True, 214 Aspect_Iterator_Element => True, 215 Aspect_Constant_Indexing => True, 216 Aspect_Default_Iterator => True, 217 Aspect_Type_Invariant => True, 218 Aspect_Unchecked_Union => True, 219 Aspect_Variable_Indexing => True, 220 Aspect_Volatile => True, 221 others => False); 222 223 -- The following array identifies all implementation defined aspects 224 225 Impl_Defined_Aspects : constant array (Aspect_Id) of Boolean := 226 (Aspect_Abstract_State => True, 227 Aspect_Ada_2005 => True, 228 Aspect_Ada_2012 => True, 229 Aspect_Compiler_Unit => True, 230 Aspect_Contract_Case => True, 231 Aspect_Contract_Cases => True, 232 Aspect_Dimension => True, 233 Aspect_Dimension_System => True, 234 Aspect_Favor_Top_Level => True, 235 Aspect_Global => True, 236 Aspect_Inline_Always => True, 237 Aspect_Invariant => True, 238 Aspect_Lock_Free => True, 239 Aspect_Object_Size => True, 240 Aspect_Persistent_BSS => True, 241 Aspect_Predicate => True, 242 Aspect_Preelaborate_05 => True, 243 Aspect_Pure_05 => True, 244 Aspect_Pure_12 => True, 245 Aspect_Pure_Function => True, 246 Aspect_Remote_Access_Type => True, 247 Aspect_Scalar_Storage_Order => True, 248 Aspect_Shared => True, 249 Aspect_Simple_Storage_Pool => True, 250 Aspect_Simple_Storage_Pool_Type => True, 251 Aspect_Suppress_Debug_Info => True, 252 Aspect_Test_Case => True, 253 Aspect_Universal_Aliasing => True, 254 Aspect_Universal_Data => True, 255 Aspect_Unmodified => True, 256 Aspect_Unreferenced => True, 257 Aspect_Unreferenced_Objects => True, 258 Aspect_Value_Size => True, 259 Aspect_Warnings => True, 260 others => False); 261 262 -- The following array indicates aspects for which multiple occurrences of 263 -- the same aspect attached to the same declaration are allowed. 264 265 No_Duplicates_Allowed : constant array (Aspect_Id) of Boolean := 266 (Aspect_Contract_Case => False, 267 Aspect_Test_Case => False, 268 others => True); 269 270 -- The following array indicates type aspects that are inherited and apply 271 -- to the class-wide type as well. 272 273 Inherited_Aspect : constant array (Aspect_Id) of Boolean := 274 (Aspect_Constant_Indexing => True, 275 Aspect_Default_Iterator => True, 276 Aspect_Implicit_Dereference => True, 277 Aspect_Iterator_Element => True, 278 Aspect_Remote_Types => True, 279 Aspect_Variable_Indexing => True, 280 others => False); 281 282 -- The following subtype defines aspects corresponding to library unit 283 -- pragmas, these can only validly appear as aspects for library units, 284 -- and result in a corresponding pragma being inserted immediately after 285 -- the occurrence of the aspect. 286 287 subtype Library_Unit_Aspects is 288 Aspect_Id range Aspect_All_Calls_Remote .. Aspect_Universal_Data; 289 290 -- The following subtype defines aspects accepting an optional static 291 -- boolean parameter indicating if the aspect should be active or 292 -- cancelling. If the parameter is missing the effective value is True, 293 -- enabling the aspect. If the parameter is present it must be a static 294 -- expression of type Standard.Boolean. If the value is True, then the 295 -- aspect is enabled. If it is False, the aspect is disabled. 296 297 subtype Boolean_Aspects is 298 Aspect_Id range Aspect_Ada_2005 .. Aspect_Id'Last; 299 300 subtype Pre_Post_Aspects is 301 Aspect_Id range Aspect_Post .. Aspect_Precondition; 302 303 -- The following type is used for indicating allowed expression forms 304 305 type Aspect_Expression is 306 (Optional, -- Optional boolean expression 307 Expression, -- Required expression 308 Name); -- Required name 309 310 -- The following array indicates what argument type is required 311 312 Aspect_Argument : constant array (Aspect_Id) of Aspect_Expression := 313 (No_Aspect => Optional, 314 Aspect_Abstract_State => Expression, 315 Aspect_Address => Expression, 316 Aspect_Alignment => Expression, 317 Aspect_Attach_Handler => Expression, 318 Aspect_Bit_Order => Expression, 319 Aspect_Component_Size => Expression, 320 Aspect_Constant_Indexing => Name, 321 Aspect_Contract_Case => Expression, 322 Aspect_Contract_Cases => Expression, 323 Aspect_Convention => Name, 324 Aspect_CPU => Expression, 325 Aspect_Default_Component_Value => Expression, 326 Aspect_Default_Iterator => Name, 327 Aspect_Default_Value => Expression, 328 Aspect_Dimension => Expression, 329 Aspect_Dimension_System => Expression, 330 Aspect_Dispatching_Domain => Expression, 331 Aspect_Dynamic_Predicate => Expression, 332 Aspect_External_Name => Expression, 333 Aspect_External_Tag => Expression, 334 Aspect_Global => Expression, 335 Aspect_Implicit_Dereference => Name, 336 Aspect_Input => Name, 337 Aspect_Interrupt_Priority => Expression, 338 Aspect_Invariant => Expression, 339 Aspect_Iterator_Element => Name, 340 Aspect_Link_Name => Expression, 341 Aspect_Machine_Radix => Expression, 342 Aspect_Object_Size => Expression, 343 Aspect_Output => Name, 344 Aspect_Post => Expression, 345 Aspect_Postcondition => Expression, 346 Aspect_Pre => Expression, 347 Aspect_Precondition => Expression, 348 Aspect_Predicate => Expression, 349 Aspect_Priority => Expression, 350 Aspect_Read => Name, 351 Aspect_Relative_Deadline => Expression, 352 Aspect_Scalar_Storage_Order => Expression, 353 Aspect_Simple_Storage_Pool => Name, 354 Aspect_Size => Expression, 355 Aspect_Small => Expression, 356 Aspect_Static_Predicate => Expression, 357 Aspect_Storage_Pool => Name, 358 Aspect_Storage_Size => Expression, 359 Aspect_Stream_Size => Expression, 360 Aspect_Suppress => Name, 361 Aspect_Synchronization => Name, 362 Aspect_Test_Case => Expression, 363 Aspect_Type_Invariant => Expression, 364 Aspect_Unsuppress => Name, 365 Aspect_Value_Size => Expression, 366 Aspect_Variable_Indexing => Name, 367 Aspect_Warnings => Name, 368 Aspect_Write => Name, 369 370 Library_Unit_Aspects => Optional, 371 Boolean_Aspects => Optional); 372 373 ----------------------------------------- 374 -- Table Linking Names and Aspect_Id's -- 375 ----------------------------------------- 376 377 -- Table linking aspect names and id's 378 379 Aspect_Names : constant array (Aspect_Id) of Name_Id := ( 380 No_Aspect => No_Name, 381 Aspect_Abstract_State => Name_Abstract_State, 382 Aspect_Ada_2005 => Name_Ada_2005, 383 Aspect_Ada_2012 => Name_Ada_2012, 384 Aspect_Address => Name_Address, 385 Aspect_Alignment => Name_Alignment, 386 Aspect_All_Calls_Remote => Name_All_Calls_Remote, 387 Aspect_Asynchronous => Name_Asynchronous, 388 Aspect_Atomic => Name_Atomic, 389 Aspect_Atomic_Components => Name_Atomic_Components, 390 Aspect_Attach_Handler => Name_Attach_Handler, 391 Aspect_Bit_Order => Name_Bit_Order, 392 Aspect_Compiler_Unit => Name_Compiler_Unit, 393 Aspect_Component_Size => Name_Component_Size, 394 Aspect_Constant_Indexing => Name_Constant_Indexing, 395 Aspect_Contract_Case => Name_Contract_Case, 396 Aspect_Contract_Cases => Name_Contract_Cases, 397 Aspect_Convention => Name_Convention, 398 Aspect_CPU => Name_CPU, 399 Aspect_Default_Iterator => Name_Default_Iterator, 400 Aspect_Default_Value => Name_Default_Value, 401 Aspect_Default_Component_Value => Name_Default_Component_Value, 402 Aspect_Dimension => Name_Dimension, 403 Aspect_Dimension_System => Name_Dimension_System, 404 Aspect_Discard_Names => Name_Discard_Names, 405 Aspect_Dispatching_Domain => Name_Dispatching_Domain, 406 Aspect_Dynamic_Predicate => Name_Dynamic_Predicate, 407 Aspect_Elaborate_Body => Name_Elaborate_Body, 408 Aspect_External_Name => Name_External_Name, 409 Aspect_External_Tag => Name_External_Tag, 410 Aspect_Export => Name_Export, 411 Aspect_Favor_Top_Level => Name_Favor_Top_Level, 412 Aspect_Global => Name_Global, 413 Aspect_Implicit_Dereference => Name_Implicit_Dereference, 414 Aspect_Import => Name_Import, 415 Aspect_Independent => Name_Independent, 416 Aspect_Independent_Components => Name_Independent_Components, 417 Aspect_Inline => Name_Inline, 418 Aspect_Inline_Always => Name_Inline_Always, 419 Aspect_Input => Name_Input, 420 Aspect_Interrupt_Handler => Name_Interrupt_Handler, 421 Aspect_Interrupt_Priority => Name_Interrupt_Priority, 422 Aspect_Invariant => Name_Invariant, 423 Aspect_Iterator_Element => Name_Iterator_Element, 424 Aspect_Link_Name => Name_Link_Name, 425 Aspect_Lock_Free => Name_Lock_Free, 426 Aspect_Machine_Radix => Name_Machine_Radix, 427 Aspect_No_Return => Name_No_Return, 428 Aspect_Object_Size => Name_Object_Size, 429 Aspect_Output => Name_Output, 430 Aspect_Pack => Name_Pack, 431 Aspect_Persistent_BSS => Name_Persistent_BSS, 432 Aspect_Post => Name_Post, 433 Aspect_Postcondition => Name_Postcondition, 434 Aspect_Pre => Name_Pre, 435 Aspect_Precondition => Name_Precondition, 436 Aspect_Predicate => Name_Predicate, 437 Aspect_Preelaborable_Initialization => Name_Preelaborable_Initialization, 438 Aspect_Preelaborate => Name_Preelaborate, 439 Aspect_Preelaborate_05 => Name_Preelaborate_05, 440 Aspect_Priority => Name_Priority, 441 Aspect_Pure => Name_Pure, 442 Aspect_Pure_05 => Name_Pure_05, 443 Aspect_Pure_12 => Name_Pure_12, 444 Aspect_Pure_Function => Name_Pure_Function, 445 Aspect_Read => Name_Read, 446 Aspect_Relative_Deadline => Name_Relative_Deadline, 447 Aspect_Remote_Access_Type => Name_Remote_Access_Type, 448 Aspect_Remote_Call_Interface => Name_Remote_Call_Interface, 449 Aspect_Remote_Types => Name_Remote_Types, 450 Aspect_Scalar_Storage_Order => Name_Scalar_Storage_Order, 451 Aspect_Shared => Name_Shared, 452 Aspect_Shared_Passive => Name_Shared_Passive, 453 Aspect_Simple_Storage_Pool => Name_Simple_Storage_Pool, 454 Aspect_Simple_Storage_Pool_Type => Name_Simple_Storage_Pool_Type, 455 Aspect_Size => Name_Size, 456 Aspect_Small => Name_Small, 457 Aspect_Static_Predicate => Name_Static_Predicate, 458 Aspect_Storage_Pool => Name_Storage_Pool, 459 Aspect_Storage_Size => Name_Storage_Size, 460 Aspect_Stream_Size => Name_Stream_Size, 461 Aspect_Suppress => Name_Suppress, 462 Aspect_Suppress_Debug_Info => Name_Suppress_Debug_Info, 463 Aspect_Synchronization => Name_Synchronization, 464 Aspect_Test_Case => Name_Test_Case, 465 Aspect_Type_Invariant => Name_Type_Invariant, 466 Aspect_Unchecked_Union => Name_Unchecked_Union, 467 Aspect_Universal_Aliasing => Name_Universal_Aliasing, 468 Aspect_Universal_Data => Name_Universal_Data, 469 Aspect_Unmodified => Name_Unmodified, 470 Aspect_Unreferenced => Name_Unreferenced, 471 Aspect_Unreferenced_Objects => Name_Unreferenced_Objects, 472 Aspect_Unsuppress => Name_Unsuppress, 473 Aspect_Value_Size => Name_Value_Size, 474 Aspect_Variable_Indexing => Name_Variable_Indexing, 475 Aspect_Volatile => Name_Volatile, 476 Aspect_Volatile_Components => Name_Volatile_Components, 477 Aspect_Warnings => Name_Warnings, 478 Aspect_Write => Name_Write); 479 480 function Get_Aspect_Id (Name : Name_Id) return Aspect_Id; 481 pragma Inline (Get_Aspect_Id); 482 -- Given a name Nam, returns the corresponding aspect id value. If the name 483 -- does not match any aspect, then No_Aspect is returned as the result. 484 485 --------------------------------------------------- 486 -- Handling of Aspect Specifications in the Tree -- 487 --------------------------------------------------- 488 489 -- Several kinds of declaration node permit aspect specifications in Ada 490 -- 2012 mode. If there was room in all the corresponding declaration nodes, 491 -- we could just have a field Aspect_Specifications pointing to a list of 492 -- nodes for the aspects (N_Aspect_Specification nodes). But there isn't 493 -- room, so we adopt a different approach. 494 495 -- The following subprograms provide access to a specialized interface 496 -- implemented internally with a hash table in the body, that provides 497 -- access to aspect specifications. 498 499 function Permits_Aspect_Specifications (N : Node_Id) return Boolean; 500 -- Returns True if the node N is a declaration node that permits aspect 501 -- specifications in the grammar. It is possible for other nodes to have 502 -- aspect specifications as a result of Rewrite or Replace calls. 503 504 function Aspect_Specifications (N : Node_Id) return List_Id; 505 -- Given a node N, returns the list of N_Aspect_Specification nodes that 506 -- are attached to this declaration node. If the node is in the class of 507 -- declaration nodes that permit aspect specifications, as defined by the 508 -- predicate above, and if their Has_Aspects flag is set to True, then this 509 -- will always be a non-empty list. If this flag is set to False, then 510 -- No_List is returned. Normally, the only nodes that have Has_Aspects set 511 -- True are the nodes for which Permits_Aspect_Specifications would return 512 -- True (i.e. the declaration nodes defined in the RM as permitting the 513 -- presence of Aspect_Specifications). However, it is possible for the 514 -- flag Has_Aspects to be set on other nodes as a result of Rewrite and 515 -- Replace calls, and this function may be used to retrieve the aspect 516 -- specifications for the original rewritten node in such cases. 517 518 procedure Set_Aspect_Specifications (N : Node_Id; L : List_Id); 519 -- The node N must be in the class of declaration nodes that permit aspect 520 -- specifications and the Has_Aspects flag must be False on entry. L must 521 -- be a non-empty list of N_Aspect_Specification nodes. This procedure sets 522 -- the Has_Aspects flag to True, and makes an entry that can be retrieved 523 -- by a subsequent Aspect_Specifications call. It is an error to call this 524 -- procedure with a node that does not permit aspect specifications, or a 525 -- node that has its Has_Aspects flag set True on entry, or with L being an 526 -- empty list or No_List. 527 528 function Find_Aspect (Ent : Entity_Id; A : Aspect_Id) return Node_Id; 529 -- Find value of a given aspect from aspect list of entity 530 531 procedure Move_Aspects (From : Node_Id; To : Node_Id); 532 -- Moves aspects from 'From' node to 'To' node. Has_Aspects (To) must be 533 -- False on entry. If Has_Aspects (From) is False, the call has no effect. 534 -- Otherwise the aspects are moved and on return Has_Aspects (To) is True, 535 -- and Has_Aspects (From) is False. 536 537 function Same_Aspect (A1 : Aspect_Id; A2 : Aspect_Id) return Boolean; 538 -- Returns True if A1 and A2 are (essentially) the same aspect. This is not 539 -- a simple equality test because e.g. Post and Postcondition are the same. 540 -- This is used for detecting duplicate aspects. 541 542 procedure Tree_Write; 543 -- Writes contents of Aspect_Specifications hash table to the tree file 544 545 procedure Tree_Read; 546 -- Reads contents of Aspect_Specifications hash table from the tree file 547 548end Aspects; 549