1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                              P A R . C H 7                               --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2013, 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.  See the GNU General Public License --
17-- for  more details.  You should have  received  a copy of the GNU General --
18-- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
19-- http://www.gnu.org/licenses for a complete copy of the license.          --
20--                                                                          --
21-- GNAT was originally developed  by the GNAT team at  New York University. --
22-- Extensive contributions were provided by Ada Core Technologies Inc.      --
23--                                                                          --
24------------------------------------------------------------------------------
25
26pragma Style_Checks (All_Checks);
27--  Turn off subprogram body ordering check. Subprograms are in order
28--  by RM section rather than alphabetical
29
30separate (Par)
31package body Ch7 is
32
33   ---------------------------------------------
34   -- 7.1  Package (also 8.5.3, 10.1.3, 12.3) --
35   ---------------------------------------------
36
37   --  This routine scans out a package declaration, package body, or a
38   --  renaming declaration or generic instantiation starting with PACKAGE
39
40   --  PACKAGE_DECLARATION ::=
41   --    PACKAGE_SPECIFICATION;
42
43   --  PACKAGE_SPECIFICATION ::=
44   --    package DEFINING_PROGRAM_UNIT_NAME
45   --      [ASPECT_SPECIFICATIONS]
46   --    is
47   --      {BASIC_DECLARATIVE_ITEM}
48   --    [private
49   --      {BASIC_DECLARATIVE_ITEM}]
50   --    end [[PARENT_UNIT_NAME .] IDENTIFIER]
51
52   --  PACKAGE_BODY ::=
53   --    package body DEFINING_PROGRAM_UNIT_NAME
54   --      [ASPECT_SPECIFICATIONS]
55   --    is
56   --      DECLARATIVE_PART
57   --    [begin
58   --      HANDLED_SEQUENCE_OF_STATEMENTS]
59   --    end [[PARENT_UNIT_NAME .] IDENTIFIER]
60
61   --  PACKAGE_RENAMING_DECLARATION ::=
62   --    package DEFINING_IDENTIFIER renames package_NAME
63   --      [ASPECT_SPECIFICATIONS];
64
65   --  PACKAGE_BODY_STUB ::=
66   --    package body DEFINING_IDENTIFIER is separate
67   --      [ASPECT_SPECIFICATIONS];
68
69   --  PACKAGE_INSTANTIATION ::=
70   --    package DEFINING_PROGRAM_UNIT_NAME is
71   --      new generic_package_NAME [GENERIC_ACTUAL_PART]
72   --        [ASPECT_SPECIFICATIONS];
73
74   --  The value in Pf_Flags indicates which of these possible declarations
75   --  is acceptable to the caller:
76
77   --    Pf_Flags.Spcn                 Set if specification OK
78   --    Pf_Flags.Decl                 Set if declaration OK
79   --    Pf_Flags.Gins                 Set if generic instantiation OK
80   --    Pf_Flags.Pbod                 Set if proper body OK
81   --    Pf_Flags.Rnam                 Set if renaming declaration OK
82   --    Pf_Flags.Stub                 Set if body stub OK
83
84   --  If an inappropriate form is encountered, it is scanned out but an error
85   --  message indicating that it is appearing in an inappropriate context is
86   --  issued. The only possible settings for Pf_Flags are those defined as
87   --  constants in package Par.
88
89   --  Note: in all contexts where a package specification is required, there
90   --  is a terminating semicolon. This semicolon is scanned out in the case
91   --  where Pf_Flags is set to Pf_Spcn, even though it is not strictly part
92   --  of the package specification (it's just too much trouble, and really
93   --  quite unnecessary, to deal with scanning out an END where the semicolon
94   --  after the END is not considered to be part of the END.
95
96   --  The caller has checked that the initial token is PACKAGE
97
98   --  Error recovery: cannot raise Error_Resync
99
100   function P_Package (Pf_Flags : Pf_Rec) return Node_Id is
101      Package_Node       : Node_Id;
102      Specification_Node : Node_Id;
103      Name_Node          : Node_Id;
104      Package_Sloc       : Source_Ptr;
105
106      Aspect_Sloc : Source_Ptr := No_Location;
107      --  Save location of WITH for scanned aspects. Left set to No_Location
108      --  if no aspects scanned before the IS keyword.
109
110      Is_Sloc : Source_Ptr;
111      --  Save location of IS token for package declaration
112
113      Dummy_Node : constant Node_Id :=
114                     New_Node (N_Package_Specification, Token_Ptr);
115      --  Dummy node to attach aspect specifications to until we properly
116      --  figure out where they eventually belong.
117
118      Body_Is_Hidden_In_SPARK         : Boolean;
119      Private_Part_Is_Hidden_In_SPARK : Boolean;
120      Hidden_Region_Start             : Source_Ptr;
121
122   begin
123      Push_Scope_Stack;
124      Scope.Table (Scope.Last).Etyp := E_Name;
125      Scope.Table (Scope.Last).Ecol := Start_Column;
126      Scope.Table (Scope.Last).Lreq := False;
127
128      Package_Sloc := Token_Ptr;
129      Scan; -- past PACKAGE
130
131      if Token = Tok_Type then
132         Error_Msg_SC -- CODEFIX
133           ("TYPE not allowed here");
134         Scan; -- past TYPE
135      end if;
136
137      --  Case of package body. Note that we demand a package body if that
138      --  is the only possibility (even if the BODY keyword is not present)
139
140      if Token = Tok_Body or else Pf_Flags = Pf_Pbod_Pexp then
141         if not Pf_Flags.Pbod then
142            Error_Msg_SC ("package body cannot appear here!");
143         end if;
144
145         T_Body;
146         Scope.Table (Scope.Last).Sloc := Token_Ptr;
147         Name_Node := P_Defining_Program_Unit_Name;
148         Scope.Table (Scope.Last).Labl := Name_Node;
149
150         if Aspect_Specifications_Present then
151            Aspect_Sloc := Token_Ptr;
152            P_Aspect_Specifications (Dummy_Node, Semicolon => False);
153         end if;
154
155         TF_Is;
156
157         if Separate_Present then
158            if not Pf_Flags.Stub then
159               Error_Msg_SC ("body stub cannot appear here!");
160            end if;
161
162            Scan; -- past SEPARATE
163
164            Package_Node := New_Node (N_Package_Body_Stub, Package_Sloc);
165            Set_Defining_Identifier (Package_Node, Name_Node);
166
167            if Has_Aspects (Dummy_Node) then
168               Error_Msg
169                 ("aspect specifications must come after SEPARATE",
170                  Aspect_Sloc);
171            end if;
172
173            P_Aspect_Specifications (Package_Node, Semicolon => False);
174            TF_Semicolon;
175            Pop_Scope_Stack;
176
177         else
178            Package_Node := New_Node (N_Package_Body, Package_Sloc);
179            Set_Defining_Unit_Name (Package_Node, Name_Node);
180
181            --  Move the aspect specifications to the body node
182
183            if Has_Aspects (Dummy_Node) then
184               Move_Aspects (From => Dummy_Node, To => Package_Node);
185            end if;
186
187            --  In SPARK, a HIDE directive can be placed at the beginning of a
188            --  package implementation, thus hiding the package body from SPARK
189            --  tool-set. No violation of the SPARK restriction should be
190            --  issued on nodes in a hidden part, which is obtained by marking
191            --  such hidden parts.
192
193            if Token = Tok_SPARK_Hide then
194               Body_Is_Hidden_In_SPARK := True;
195               Hidden_Region_Start     := Token_Ptr;
196               Scan; -- past HIDE directive
197            else
198               Body_Is_Hidden_In_SPARK := False;
199            end if;
200
201            Parse_Decls_Begin_End (Package_Node);
202
203            if Body_Is_Hidden_In_SPARK then
204               Set_Hidden_Part_In_SPARK (Hidden_Region_Start, Token_Ptr);
205            end if;
206         end if;
207
208      --  Cases other than Package_Body
209
210      else
211         Scope.Table (Scope.Last).Sloc := Token_Ptr;
212         Name_Node := P_Defining_Program_Unit_Name;
213         Scope.Table (Scope.Last).Labl := Name_Node;
214
215         --  Case of renaming declaration
216
217         Check_Misspelling_Of (Tok_Renames);
218
219         if Token = Tok_Renames then
220            if not Pf_Flags.Rnam then
221               Error_Msg_SC ("renaming declaration cannot appear here!");
222            end if;
223
224            Scan; -- past RENAMES;
225
226            Package_Node :=
227              New_Node (N_Package_Renaming_Declaration, Package_Sloc);
228            Set_Defining_Unit_Name (Package_Node, Name_Node);
229            Set_Name (Package_Node, P_Qualified_Simple_Name);
230
231            No_Constraint;
232            P_Aspect_Specifications (Package_Node, Semicolon => False);
233            TF_Semicolon;
234            Pop_Scope_Stack;
235
236         --  Generic package instantiation or package declaration
237
238         else
239            if Aspect_Specifications_Present then
240               Aspect_Sloc := Token_Ptr;
241               P_Aspect_Specifications (Dummy_Node, Semicolon => False);
242            end if;
243
244            Is_Sloc := Token_Ptr;
245            TF_Is;
246
247            --  Case of generic instantiation
248
249            if Token = Tok_New then
250               if not Pf_Flags.Gins then
251                  Error_Msg_SC
252                     ("generic instantiation cannot appear here!");
253               end if;
254
255               if Aspect_Sloc /= No_Location then
256                  Error_Msg
257                    ("misplaced aspects for package instantiation",
258                     Aspect_Sloc);
259               end if;
260
261               Scan; -- past NEW
262
263               Package_Node :=
264                 New_Node (N_Package_Instantiation, Package_Sloc);
265               Set_Defining_Unit_Name (Package_Node, Name_Node);
266               Set_Name (Package_Node, P_Qualified_Simple_Name);
267               Set_Generic_Associations
268                 (Package_Node, P_Generic_Actual_Part_Opt);
269
270               if Aspect_Sloc /= No_Location
271                 and then not Aspect_Specifications_Present
272               then
273                  Error_Msg_SC ("\info: aspect specifications belong here");
274                  Move_Aspects (From => Dummy_Node, To => Package_Node);
275               end if;
276
277               P_Aspect_Specifications (Package_Node);
278               Pop_Scope_Stack;
279
280            --  Case of package declaration or package specification
281
282            else
283               Specification_Node :=
284                 New_Node (N_Package_Specification, Package_Sloc);
285
286               Set_Defining_Unit_Name (Specification_Node, Name_Node);
287               Set_Visible_Declarations
288                 (Specification_Node, P_Basic_Declarative_Items);
289
290               if Token = Tok_Private then
291                  Error_Msg_Col := Scope.Table (Scope.Last).Ecol;
292
293                  if RM_Column_Check then
294                     if Token_Is_At_Start_Of_Line
295                       and then Start_Column /= Error_Msg_Col
296                     then
297                        Error_Msg_SC
298                          ("(style) PRIVATE in wrong column, should be@");
299                     end if;
300                  end if;
301
302                  Scan; -- past PRIVATE
303
304                  if Token = Tok_SPARK_Hide then
305                     Private_Part_Is_Hidden_In_SPARK := True;
306                     Hidden_Region_Start             := Token_Ptr;
307                     Scan; -- past HIDE directive
308                  else
309                     Private_Part_Is_Hidden_In_SPARK := False;
310                  end if;
311
312                  Set_Private_Declarations
313                    (Specification_Node, P_Basic_Declarative_Items);
314
315                  --  In SPARK, a HIDE directive can be placed at the beginning
316                  --  of a private part, thus hiding all declarations in the
317                  --  private part from SPARK tool-set. No violation of the
318                  --  SPARK restriction should be issued on nodes in a hidden
319                  --  part, which is obtained by marking such hidden parts.
320
321                  if Private_Part_Is_Hidden_In_SPARK then
322                     Set_Hidden_Part_In_SPARK (Hidden_Region_Start, Token_Ptr);
323                  end if;
324
325                  --  Deal gracefully with multiple PRIVATE parts
326
327                  while Token = Tok_Private loop
328                     Error_Msg_SC
329                       ("only one private part allowed per package");
330                     Scan; -- past PRIVATE
331                     Append_List (P_Basic_Declarative_Items,
332                       Private_Declarations (Specification_Node));
333                  end loop;
334               end if;
335
336               if Pf_Flags = Pf_Spcn then
337                  Package_Node := Specification_Node;
338               else
339                  Package_Node :=
340                    New_Node (N_Package_Declaration, Package_Sloc);
341                  Set_Specification (Package_Node, Specification_Node);
342               end if;
343
344               if Token = Tok_Begin then
345                  Error_Msg_SC ("begin block not allowed in package spec");
346                  Scan; -- past BEGIN
347                  Discard_Junk_List (P_Sequence_Of_Statements (SS_None));
348               end if;
349
350               End_Statements (Specification_Node, Empty, Is_Sloc);
351               Move_Aspects (From => Dummy_Node, To => Package_Node);
352            end if;
353         end if;
354      end if;
355
356      return Package_Node;
357   end P_Package;
358
359   ------------------------------
360   -- 7.1  Package Declaration --
361   ------------------------------
362
363   --  Parsed by P_Package (7.1)
364
365   --------------------------------
366   -- 7.1  Package Specification --
367   --------------------------------
368
369   --  Parsed by P_Package (7.1)
370
371   -----------------------
372   -- 7.1  Package Body --
373   -----------------------
374
375   --  Parsed by P_Package (7.1)
376
377   -----------------------------------
378   -- 7.3  Private Type Declaration --
379   -----------------------------------
380
381   --  Parsed by P_Type_Declaration (3.2.1)
382
383   ----------------------------------------
384   -- 7.3  Private Extension Declaration --
385   ----------------------------------------
386
387   --  Parsed by P_Type_Declaration (3.2.1)
388
389end Ch7;
390