gcc/ada/par-ch7.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              P A R . C H 7                               --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --          Copyright (C) 1992-2001 Free Software Foundation, Inc.          --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- GNAT was originally developed  by the GNAT team at  New York University. --
  24 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
  25 --                                                                          --
  26 ------------------------------------------------------------------------------
  27
  28 pragma Style_Checks (All_Checks);
  29 --  Turn off subprogram body ordering check. Subprograms are in order
  30 --  by RM section rather than alphabetical
  31
  32 separate (Par)
  33 package body Ch7 is
  34
  35    ---------------------------------------------
  36    -- 7.1  Package (also 8.5.3, 10.1.3, 12.3) --
  37    ---------------------------------------------
  38
  39    --  This routine scans out a package declaration, package body, or a
  40    --  renaming declaration or generic instantiation starting with PACKAGE
  41
  42    --  PACKAGE_DECLARATION ::= PACKAGE_SPECIFICATION;
  43
  44    --  PACKAGE_SPECIFICATION ::=
  45    --    package DEFINING_PROGRAM_UNIT_NAME is
  46    --      {BASIC_DECLARATIVE_ITEM}
  47    --    [private
  48    --      {BASIC_DECLARATIVE_ITEM}]
  49    --    end [[PARENT_UNIT_NAME .] IDENTIFIER]
  50
  51    --  PACKAGE_BODY ::=
  52    --    package body DEFINING_PROGRAM_UNIT_NAME is
  53    --      DECLARATIVE_PART
  54    --    [begin
  55    --      HANDLED_SEQUENCE_OF_STATEMENTS]
  56    --    end [[PARENT_UNIT_NAME .] IDENTIFIER]
  57
  58    --  PACKAGE_RENAMING_DECLARATION ::=
  59    --    package DEFINING_IDENTIFIER renames package_NAME;
  60
  61    --  PACKAGE_BODY_STUB ::=
  62    --    package body DEFINING_IDENTIFIER is separate;
  63
  64    --  The value in Pf_Flags indicates which of these possible declarations
  65    --  is acceptable to the caller:
  66
  67    --    Pf_Flags.Spcn                 Set if specification OK
  68    --    Pf_Flags.Decl                 Set if declaration OK
  69    --    Pf_Flags.Gins                 Set if generic instantiation OK
  70    --    Pf_Flags.Pbod                 Set if proper body OK
  71    --    Pf_Flags.Rnam                 Set if renaming declaration OK
  72    --    Pf_Flags.Stub                 Set if body stub OK
  73
  74    --  If an inappropriate form is encountered, it is scanned out but an
  75    --  error message indicating that it is appearing in an inappropriate
  76    --  context is issued. The only possible settings for Pf_Flags are those
  77    --  defined as constants in package Par.
  78
  79    --  Note: in all contexts where a package specification is required, there
  80    --  is a terminating semicolon. This semicolon is scanned out in the case
  81    --  where Pf_Flags is set to Pf_Spcn, even though it is not strictly part
  82    --  of the package specification (it's just too much trouble, and really
  83    --  quite unnecessary, to deal with scanning out an END where the semicolon
  84    --  after the END is not considered to be part of the END.
  85
  86    --  The caller has checked that the initial token is PACKAGE
  87
  88    --  Error recovery: cannot raise Error_Resync
  89
  90    function P_Package (Pf_Flags : Pf_Rec) return Node_Id is
  91       Package_Node       : Node_Id;
  92       Specification_Node : Node_Id;
  93       Name_Node          : Node_Id;
  94       Package_Sloc       : Source_Ptr;
  95
  96    begin
  97       Push_Scope_Stack;
  98       Scope.Table (Scope.Last).Etyp := E_Name;
  99       Scope.Table (Scope.Last).Ecol := Start_Column;
 100       Scope.Table (Scope.Last).Lreq := False;
 101
 102       Package_Sloc := Token_Ptr;
 103       Scan; -- past PACKAGE
 104
 105       if Token = Tok_Type then
 106          Error_Msg_SC ("TYPE not allowed here");
 107          Scan; -- past TYPE
 108       end if;
 109
 110       --  Case of package body. Note that we demand a package body if that
 111       --  is the only possibility (even if the BODY keyword is not present)
 112
 113       if Token = Tok_Body or else Pf_Flags = Pf_Pbod then
 114          if not Pf_Flags.Pbod then
 115             Error_Msg_SC ("package body cannot appear here!");
 116          end if;
 117
 118          T_Body;
 119          Name_Node := P_Defining_Program_Unit_Name;
 120          Scope.Table (Scope.Last).Labl := Name_Node;
 121          TF_Is;
 122
 123          if Separate_Present then
 124             if not Pf_Flags.Stub then
 125                Error_Msg_SC ("body stub cannot appear here!");
 126             end if;
 127
 128             Scan; -- past SEPARATE
 129             TF_Semicolon;
 130             Pop_Scope_Stack;
 131
 132             Package_Node := New_Node (N_Package_Body_Stub, Package_Sloc);
 133             Set_Defining_Identifier (Package_Node, Name_Node);
 134
 135          else
 136             Package_Node := New_Node (N_Package_Body, Package_Sloc);
 137             Set_Defining_Unit_Name (Package_Node, Name_Node);
 138             Parse_Decls_Begin_End (Package_Node);
 139          end if;
 140
 141          return Package_Node;
 142
 143       --  Cases other than Package_Body
 144
 145       else
 146          Name_Node := P_Defining_Program_Unit_Name;
 147          Scope.Table (Scope.Last).Labl := Name_Node;
 148
 149          --  Case of renaming declaration
 150
 151          Check_Misspelling_Of (Tok_Renames);
 152
 153          if Token = Tok_Renames then
 154             if not Pf_Flags.Rnam then
 155                Error_Msg_SC ("renaming declaration cannot appear here!");
 156             end if;
 157
 158             Scan; -- past RENAMES;
 159
 160             Package_Node :=
 161               New_Node (N_Package_Renaming_Declaration, Package_Sloc);
 162             Set_Defining_Unit_Name (Package_Node, Name_Node);
 163             Set_Name (Package_Node, P_Qualified_Simple_Name);
 164
 165             No_Constraint;
 166             TF_Semicolon;
 167             Pop_Scope_Stack;
 168             return Package_Node;
 169
 170          else
 171             TF_Is;
 172
 173             --  Case of generic instantiation
 174
 175             if Token = Tok_New then
 176                if not Pf_Flags.Gins then
 177                   Error_Msg_SC
 178                      ("generic instantiation cannot appear here!");
 179                end if;
 180
 181                Scan; -- past NEW
 182
 183                Package_Node :=
 184                   New_Node (N_Package_Instantiation, Package_Sloc);
 185                Set_Defining_Unit_Name (Package_Node, Name_Node);
 186                Set_Name (Package_Node, P_Qualified_Simple_Name);
 187                Set_Generic_Associations
 188                  (Package_Node, P_Generic_Actual_Part_Opt);
 189                TF_Semicolon;
 190                Pop_Scope_Stack;
 191
 192             --  Case of package declaration or package specification
 193
 194             else
 195                Specification_Node :=
 196                  New_Node (N_Package_Specification, Package_Sloc);
 197
 198                Set_Defining_Unit_Name (Specification_Node, Name_Node);
 199                Set_Visible_Declarations
 200                  (Specification_Node, P_Basic_Declarative_Items);
 201
 202                if Token = Tok_Private then
 203                   Error_Msg_Col := Scope.Table (Scope.Last).Ecol;
 204
 205                   if Style.RM_Column_Check then
 206                      if Token_Is_At_Start_Of_Line
 207                        and then Start_Column /= Error_Msg_Col
 208                      then
 209                         Error_Msg_SC
 210                           ("(style) PRIVATE in wrong column, should be@");
 211                      end if;
 212                   end if;
 213
 214                   Scan; -- past PRIVATE
 215                   Set_Private_Declarations
 216                     (Specification_Node, P_Basic_Declarative_Items);
 217
 218                   --  Deal gracefully with multiple PRIVATE parts
 219
 220                   while Token = Tok_Private loop
 221                      Error_Msg_SC
 222                        ("only one private part allowed per package");
 223                      Scan; -- past PRIVATE
 224                      Append_List (P_Basic_Declarative_Items,
 225                        Private_Declarations (Specification_Node));
 226                   end loop;
 227                end if;
 228
 229                if Pf_Flags = Pf_Spcn then
 230                   Package_Node := Specification_Node;
 231                else
 232                   Package_Node :=
 233                     New_Node (N_Package_Declaration, Package_Sloc);
 234                   Set_Specification (Package_Node, Specification_Node);
 235                end if;
 236
 237                if Token = Tok_Begin then
 238                   Error_Msg_SC ("begin block not allowed in package spec");
 239                   Scan; -- past BEGIN
 240                   Discard_Junk_List (P_Sequence_Of_Statements (SS_None));
 241                end if;
 242
 243                End_Statements (Specification_Node);
 244             end if;
 245
 246             return Package_Node;
 247          end if;
 248       end if;
 249    end P_Package;
 250
 251    ------------------------------
 252    -- 7.1  Package Declaration --
 253    ------------------------------
 254
 255    --  Parsed by P_Package (7.1)
 256
 257    --------------------------------
 258    -- 7.1  Package Specification --
 259    --------------------------------
 260
 261    --  Parsed by P_Package (7.1)
 262
 263    -----------------------
 264    -- 7.1  Package Body --
 265    -----------------------
 266
 267    --  Parsed by P_Package (7.1)
 268
 269    -----------------------------------
 270    -- 7.3  Private Type Declaration --
 271    -----------------------------------
 272
 273    --  Parsed by P_Type_Declaration (3.2.1)
 274
 275    ----------------------------------------
 276    -- 7.3  Private Extension Declaration --
 277    ----------------------------------------
 278
 279    --  Parsed by P_Type_Declaration (3.2.1)
 280
 281 end Ch7;