1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                              P A R . C H 7                               --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2021, 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   begin
119      Push_Scope_Stack;
120      Scopes (Scope.Last).Etyp := E_Name;
121      Scopes (Scope.Last).Ecol := Start_Column;
122      Scopes (Scope.Last).Lreq := False;
123
124      Package_Sloc := Token_Ptr;
125      Scan; -- past PACKAGE
126
127      if Token = Tok_Type then
128         Error_Msg_SC -- CODEFIX
129           ("TYPE not allowed here");
130         Scan; -- past TYPE
131      end if;
132
133      --  Case of package body. Note that we demand a package body if that
134      --  is the only possibility (even if the BODY keyword is not present)
135
136      if Token = Tok_Body or else Pf_Flags = Pf_Pbod_Pexp then
137         if not Pf_Flags.Pbod then
138            Error_Msg_SC ("package body cannot appear here!");
139         end if;
140
141         T_Body;
142         Scopes (Scope.Last).Sloc := Token_Ptr;
143         Name_Node := P_Defining_Program_Unit_Name;
144         Scopes (Scope.Last).Labl := Name_Node;
145         Current_Node := Name_Node;
146
147         if Aspect_Specifications_Present then
148            Aspect_Sloc := Token_Ptr;
149            P_Aspect_Specifications (Dummy_Node, Semicolon => False);
150         end if;
151
152         TF_Is;
153
154         if Separate_Present then
155            if not Pf_Flags.Stub then
156               Error_Msg_SC ("body stub cannot appear here!");
157            end if;
158
159            Scan; -- past SEPARATE
160
161            Package_Node := New_Node (N_Package_Body_Stub, Package_Sloc);
162            Set_Defining_Identifier (Package_Node, Name_Node);
163
164            if Has_Aspects (Dummy_Node) then
165               Error_Msg
166                 ("aspect specifications must come after SEPARATE",
167                  Aspect_Sloc);
168            end if;
169
170            P_Aspect_Specifications (Package_Node, Semicolon => False);
171            TF_Semicolon;
172            Pop_Scope_Stack;
173
174         else
175            Package_Node := New_Node (N_Package_Body, Package_Sloc);
176            Set_Defining_Unit_Name (Package_Node, Name_Node);
177
178            --  Move the aspect specifications to the body node
179
180            if Has_Aspects (Dummy_Node) then
181               Move_Aspects (From => Dummy_Node, To => Package_Node);
182            end if;
183
184            Parse_Decls_Begin_End (Package_Node);
185         end if;
186
187      --  Cases other than Package_Body
188
189      else
190         Scopes (Scope.Last).Sloc := Token_Ptr;
191         Name_Node := P_Defining_Program_Unit_Name;
192         Scopes (Scope.Last).Labl := Name_Node;
193         Current_Node := Name_Node;
194
195         --  Case of renaming declaration
196
197         Check_Misspelling_Of (Tok_Renames);
198
199         if Token = Tok_Renames then
200            if not Pf_Flags.Rnam then
201               Error_Msg_SC ("renaming declaration cannot appear here!");
202            end if;
203
204            Scan; -- past RENAMES;
205
206            Package_Node :=
207              New_Node (N_Package_Renaming_Declaration, Package_Sloc);
208            Set_Defining_Unit_Name (Package_Node, Name_Node);
209            Set_Name (Package_Node, P_Qualified_Simple_Name);
210
211            No_Constraint;
212            P_Aspect_Specifications (Package_Node, Semicolon => False);
213            TF_Semicolon;
214            Pop_Scope_Stack;
215
216         --  Generic package instantiation or package declaration
217
218         else
219            if Aspect_Specifications_Present then
220               Aspect_Sloc := Token_Ptr;
221               P_Aspect_Specifications (Dummy_Node, Semicolon => False);
222            end if;
223
224            Is_Sloc := Token_Ptr;
225            TF_Is;
226
227            --  Case of generic instantiation
228
229            if Token = Tok_New then
230               if not Pf_Flags.Gins then
231                  Error_Msg_SC
232                     ("generic instantiation cannot appear here!");
233               end if;
234
235               if Aspect_Sloc /= No_Location then
236                  Error_Msg
237                    ("misplaced aspects for package instantiation",
238                     Aspect_Sloc);
239               end if;
240
241               Scan; -- past NEW
242
243               Package_Node :=
244                 New_Node (N_Package_Instantiation, Package_Sloc);
245               Set_Defining_Unit_Name (Package_Node, Name_Node);
246               Set_Name (Package_Node, P_Qualified_Simple_Name);
247               Set_Generic_Associations
248                 (Package_Node, P_Generic_Actual_Part_Opt);
249
250               if Aspect_Sloc /= No_Location
251                 and then not Aspect_Specifications_Present
252               then
253                  Error_Msg_SC ("info: aspect specifications belong here??");
254                  Move_Aspects (From => Dummy_Node, To => Package_Node);
255               end if;
256
257               P_Aspect_Specifications (Package_Node);
258               Pop_Scope_Stack;
259
260            --  Case of package declaration or package specification
261
262            else
263               Specification_Node :=
264                 New_Node (N_Package_Specification, Package_Sloc);
265
266               Set_Defining_Unit_Name (Specification_Node, Name_Node);
267               Set_Visible_Declarations
268                 (Specification_Node,
269                  P_Basic_Declarative_Items (Declare_Expression => False));
270
271               if Token = Tok_Private then
272                  Error_Msg_Col := Scopes (Scope.Last).Ecol;
273
274                  if RM_Column_Check then
275                     if Token_Is_At_Start_Of_Line
276                       and then Start_Column /= Error_Msg_Col
277                     then
278                        Error_Msg_SC
279                          ("(style) PRIVATE in wrong column, should be@");
280                     end if;
281                  end if;
282
283                  Scan; -- past PRIVATE
284
285                  Set_Private_Declarations
286                    (Specification_Node,
287                     P_Basic_Declarative_Items (Declare_Expression => False));
288
289                  --  Deal gracefully with multiple PRIVATE parts
290
291                  while Token = Tok_Private loop
292                     Error_Msg_SC
293                       ("only one private part allowed per package");
294                     Scan; -- past PRIVATE
295                     Append_List
296                       (P_Basic_Declarative_Items
297                          (Declare_Expression => False),
298                        Private_Declarations (Specification_Node));
299                  end loop;
300               end if;
301
302               if Pf_Flags = Pf_Spcn then
303                  Package_Node := Specification_Node;
304               else
305                  Package_Node :=
306                    New_Node (N_Package_Declaration, Package_Sloc);
307                  Set_Specification (Package_Node, Specification_Node);
308               end if;
309
310               if Token = Tok_Begin then
311                  Error_Msg_SC ("begin block not allowed in package spec");
312                  Scan; -- past BEGIN
313                  Discard_Junk_List (P_Sequence_Of_Statements (SS_None));
314               end if;
315
316               End_Statements (Specification_Node, Empty, Is_Sloc);
317               Move_Aspects (From => Dummy_Node, To => Package_Node);
318            end if;
319         end if;
320      end if;
321
322      return Package_Node;
323   end P_Package;
324
325   ------------------------------
326   -- 7.1  Package Declaration --
327   ------------------------------
328
329   --  Parsed by P_Package (7.1)
330
331   --------------------------------
332   -- 7.1  Package Specification --
333   --------------------------------
334
335   --  Parsed by P_Package (7.1)
336
337   -----------------------
338   -- 7.1  Package Body --
339   -----------------------
340
341   --  Parsed by P_Package (7.1)
342
343   -----------------------------------
344   -- 7.3  Private Type Declaration --
345   -----------------------------------
346
347   --  Parsed by P_Type_Declaration (3.2.1)
348
349   ----------------------------------------
350   -- 7.3  Private Extension Declaration --
351   ----------------------------------------
352
353   --  Parsed by P_Type_Declaration (3.2.1)
354
355end Ch7;
356