X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fada%2Fg-awk.adb;h=0dee657b140f6208b57d81e0c8641ecf3e869049;hb=e2b35abeb5c6a6e396c0134b837f5f9549b1e295;hp=7811caec00b960608a831f400498c31b4f1bb15f;hpb=83cce46b47d48de4c71b02a20f5bf36296a48568;p=pf3gnuchains%2Fgcc-fork.git

diff --git a/gcc/ada/g-awk.adb b/gcc/ada/g-awk.adb
index 7811caec00b..0dee657b140 100644
--- a/gcc/ada/g-awk.adb
+++ b/gcc/ada/g-awk.adb
@@ -6,9 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---                            $Revision: 1.10 $
---                                                                          --
---            Copyright (C) 2000-2001 Ada Core Technologies, Inc.           --
+--                     Copyright (C) 2000-2008, AdaCore                     --
 --                                                                          --
 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
 -- terms of the  GNU General Public License as published  by the Free Soft- --
@@ -18,8 +16,8 @@
 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
 -- for  more details.  You should have  received  a copy of the GNU General --
 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
--- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
--- MA 02111-1307, USA.                                                      --
+-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
+-- Boston, MA 02110-1301, USA.                                              --
 --                                                                          --
 -- As a special exception,  if other files  instantiate  generics from this --
 -- unit, or you link  this unit with other files  to produce an executable, --
@@ -28,13 +26,15 @@
 -- however invalidate  any other reasons why  the executable file  might be --
 -- covered by the  GNU Public License.                                      --
 --                                                                          --
--- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com).   --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
 --                                                                          --
 ------------------------------------------------------------------------------
 
-pragma Style_Checks (All_Checks);
---  Turn off alpha ordering check for subprograms, since we cannot
---  Put Finalize and Initialize in alpha order (see comments).
+pragma Ada_95;
+--  This is needed because the pragmas Warnings (Off) in Current_Session and
+--  Default_Session (see below) do not work when compiling clients of this
+--  package that instantiate generic units herein.
 
 with Ada.Exceptions;
 with Ada.Text_IO;
@@ -52,6 +52,18 @@ package body GNAT.AWK is
    use Ada;
    use Ada.Strings.Unbounded;
 
+   -----------------------
+   -- Local subprograms --
+   -----------------------
+
+   --  The following two subprograms provide a functional interface to the
+   --  two special session variables, that are manipulated explicitly by
+   --  Finalize, but must be declared after Finalize to prevent static
+   --  elaboration warnings.
+
+   function Get_Def return Session_Data_Access;
+   procedure Set_Cur;
+
    ----------------
    -- Split mode --
    ----------------
@@ -66,7 +78,7 @@ package body GNAT.AWK is
 
       procedure Current_Line (S : Mode; Session : Session_Type)
         is abstract;
-      --  Split Session's current line using split mode.
+      --  Split current line of Session using split mode S
 
       ------------------------
       -- Split on separator --
@@ -103,7 +115,7 @@ package body GNAT.AWK is
 
    package File_Table is
       new Dynamic_Tables (AWK_File, Natural, 1, 5, 50);
-   --  List of filename associated with a Session.
+   --  List of file names associated with a Session
 
    procedure Free is new Unchecked_Deallocation (String, AWK_File);
 
@@ -115,17 +127,17 @@ package body GNAT.AWK is
       First : Positive;
       Last  : Natural;
    end record;
-   --  This is a field slice (First .. Last) in session's current line.
+   --  This is a field slice (First .. Last) in session's current line
 
    package Field_Table is
       new Dynamic_Tables (Field_Slice, Natural, 1, 10, 100);
-   --  List of fields for the current line.
+   --  List of fields for the current line
 
    --------------
    -- Patterns --
    --------------
 
-   --  Define all patterns style : exact string, regular expression, boolean
+   --  Define all patterns style: exact string, regular expression, boolean
    --  function.
 
    package Patterns is
@@ -138,13 +150,12 @@ package body GNAT.AWK is
 
       function Match
         (P       : Pattern;
-         Session : Session_Type)
-         return    Boolean
+         Session : Session_Type) return Boolean
       is abstract;
-      --  Returns True if P match for the current session and False otherwise.
+      --  Returns True if P match for the current session and False otherwise
 
       procedure Release (P : in out Pattern);
-      --  Release memory used by the pattern structure.
+      --  Release memory used by the pattern structure
 
       --------------------------
       -- Exact string pattern --
@@ -157,8 +168,7 @@ package body GNAT.AWK is
 
       function Match
         (P       : String_Pattern;
-         Session : Session_Type)
-         return    Boolean;
+         Session : Session_Type) return Boolean;
 
       --------------------------------
       -- Regular expression pattern --
@@ -173,8 +183,7 @@ package body GNAT.AWK is
 
       function Match
         (P       : Regexp_Pattern;
-         Session : Session_Type)
-         return    Boolean;
+         Session : Session_Type) return Boolean;
 
       procedure Release (P : in out Regexp_Pattern);
 
@@ -188,8 +197,7 @@ package body GNAT.AWK is
 
       function Match
         (P       : Callback_Pattern;
-         Session : Session_Type)
-         return    Boolean;
+         Session : Session_Type) return Boolean;
 
    end Patterns;
 
@@ -212,9 +220,8 @@ package body GNAT.AWK is
 
       procedure Call
         (A       : Action;
-         Session : Session_Type)
-         is abstract;
-      --  Call action A as required.
+         Session : Session_Type) is abstract;
+      --  Call action A as required
 
       -------------------
       -- Simple action --
@@ -272,12 +279,30 @@ package body GNAT.AWK is
       NR           : Natural := 0;
       FNR          : Natural := 0;
       Matches      : Regpat.Match_Array (0 .. 100);
-      --  latest matches for the regexp pattern
+      --  Latest matches for the regexp pattern
    end record;
 
    procedure Free is
       new Unchecked_Deallocation (Session_Data, Session_Data_Access);
 
+   --------------
+   -- Finalize --
+   --------------
+
+   procedure Finalize (Session : in out Session_Type) is
+   begin
+      --  We release the session data only if it is not the default session
+
+      if Session.Data /= Get_Def then
+         Free (Session.Data);
+
+         --  Since we have closed the current session, set it to point now to
+         --  the default session.
+
+         Set_Cur;
+      end if;
+   end Finalize;
+
    ----------------
    -- Initialize --
    ----------------
@@ -302,50 +327,24 @@ package body GNAT.AWK is
    -- Session Variables --
    -----------------------
 
-   --  These must come after the body of Initialize, since they make
-   --  implicit calls to Initialize at elaboration time.
-
    Def_Session : Session_Type;
    Cur_Session : Session_Type;
 
-   --------------
-   -- Finalize --
-   --------------
-
-   --  Note: Finalize must come after Initialize and the definition
-   --  of the Def_Session and Cur_Session variables, since it references
-   --  the latter.
-
-   procedure Finalize (Session : in out Session_Type) is
-   begin
-      --  We release the session data only if it is not the default session.
-
-      if Session.Data /= Def_Session.Data then
-         Free (Session.Data);
-
-         --  Since we have closed the current session, set it to point
-         --  now to the default session.
-
-         Cur_Session.Data := Def_Session.Data;
-      end if;
-   end Finalize;
-
    ----------------------
    -- Private Services --
    ----------------------
 
    function Always_True return Boolean;
-   --  A function that always returns True.
+   --  A function that always returns True
 
    function Apply_Filters
-     (Session : Session_Type := Current_Session)
-      return    Boolean;
+     (Session : Session_Type) return Boolean;
    --  Apply any filters for which the Pattern is True for Session. It returns
    --  True if a least one filters has been applied (i.e. associated action
    --  callback has been called).
 
    procedure Open_Next_File
-     (Session : Session_Type := Current_Session);
+     (Session : Session_Type);
    pragma Inline (Open_Next_File);
    --  Open next file for Session closing current file if needed. It raises
    --  End_Error if there is no more file in the table.
@@ -359,7 +358,7 @@ package body GNAT.AWK is
    --  number and the filename if possible.
 
    procedure Read_Line (Session : Session_Type);
-   --  Read a line for the Session and set Current_Line.
+   --  Read a line for the Session and set Current_Line
 
    procedure Split_Line (Session : Session_Type);
    --  Split session's Current_Line according to the session separators and
@@ -383,6 +382,7 @@ package body GNAT.AWK is
         (A       : Simple_Action;
          Session : Session_Type)
       is
+         pragma Unreferenced (Session);
       begin
          A.Proc.all;
       end Call;
@@ -413,8 +413,7 @@ package body GNAT.AWK is
 
       function Match
         (P       : String_Pattern;
-         Session : Session_Type)
-         return    Boolean
+         Session : Session_Type) return Boolean
       is
       begin
          return P.Str = Field (P.Rank, Session);
@@ -426,11 +425,9 @@ package body GNAT.AWK is
 
       function Match
         (P       : Regexp_Pattern;
-         Session : Session_Type)
-         return    Boolean
+         Session : Session_Type) return Boolean
       is
          use type Regpat.Match_Location;
-
       begin
          Regpat.Match
            (P.Regx.all, Field (P.Rank, Session), Session.Data.Matches);
@@ -443,9 +440,9 @@ package body GNAT.AWK is
 
       function Match
         (P       : Callback_Pattern;
-         Session : Session_Type)
-         return    Boolean
+         Session : Session_Type) return Boolean
       is
+         pragma Unreferenced (Session);
       begin
          return P.Pattern.all;
       end Match;
@@ -455,6 +452,7 @@ package body GNAT.AWK is
       -------------
 
       procedure Release (P : in out Pattern) is
+         pragma Unreferenced (P);
       begin
          null;
       end Release;
@@ -466,7 +464,6 @@ package body GNAT.AWK is
       procedure Release (P : in out Regexp_Pattern) is
          procedure Free is new Unchecked_Deallocation
            (Regpat.Pattern_Matcher, Pattern_Matcher_Access);
-
       begin
          Free (P.Regx);
       end Release;
@@ -489,10 +486,10 @@ package body GNAT.AWK is
          Line   : constant String := To_String (Session.Data.Current_Line);
          Fields : Field_Table.Instance renames Session.Data.Fields;
 
-         Start : Positive;
+         Start : Natural;
          Stop  : Natural;
 
-         Seps  : Maps.Character_Set := Maps.To_Set (S.Separators);
+         Seps  : constant Maps.Character_Set := Maps.To_Set (S.Separators);
 
       begin
          --  First field start here
@@ -516,7 +513,7 @@ package body GNAT.AWK is
 
             Fields.Table (Field_Table.Last (Fields)).Last := Stop - 1;
 
-            --  if separators are set to the default (space and tab) we skip
+            --  If separators are set to the default (space and tab) we skip
             --  all spaces and tabs following current field.
 
             if S.Separators = Default_Separators then
@@ -525,6 +522,10 @@ package body GNAT.AWK is
                   Maps.To_Set (Default_Separators),
                   Outside,
                   Strings.Forward);
+
+               if Start = 0 then
+                  Start := Stop + 1;
+               end if;
             else
                Start := Stop + 1;
             end if;
@@ -585,7 +586,7 @@ package body GNAT.AWK is
 
    procedure Add_File
      (Filename : String;
-      Session  : Session_Type := Current_Session)
+      Session  : Session_Type)
    is
       Files : File_Table.Instance renames Session.Data.Files;
 
@@ -601,6 +602,14 @@ package body GNAT.AWK is
       end if;
    end Add_File;
 
+   procedure Add_File
+     (Filename : String)
+   is
+
+   begin
+      Add_File (Filename, Cur_Session);
+   end Add_File;
+
    ---------------
    -- Add_Files --
    ---------------
@@ -609,7 +618,7 @@ package body GNAT.AWK is
      (Directory             : String;
       Filenames             : String;
       Number_Of_Files_Added : out Natural;
-      Session               : Session_Type := Current_Session)
+      Session               : Session_Type)
    is
       use Directory_Operations;
 
@@ -636,11 +645,21 @@ package body GNAT.AWK is
       when others =>
          Raise_With_Info
            (File_Error'Identity,
-            "Error scaning directory " & Directory
+            "Error scanning directory " & Directory
             & " for files " & Filenames & '.',
             Session);
    end Add_Files;
 
+   procedure Add_Files
+     (Directory             : String;
+      Filenames             : String;
+      Number_Of_Files_Added : out Natural)
+   is
+
+   begin
+      Add_Files (Directory, Filenames, Number_Of_Files_Added, Cur_Session);
+   end Add_Files;
+
    -----------------
    -- Always_True --
    -----------------
@@ -655,14 +674,13 @@ package body GNAT.AWK is
    -------------------
 
    function Apply_Filters
-     (Session : Session_Type := Current_Session)
-      return    Boolean
+     (Session : Session_Type) return Boolean
    is
       Filters : Pattern_Action_Table.Instance renames Session.Data.Filters;
       Results : Boolean := False;
 
    begin
-      --  Iterate throught the filters table, if pattern match call action.
+      --  Iterate through the filters table, if pattern match call action
 
       for F in 1 .. Pattern_Action_Table.Last (Filters) loop
          if Patterns.Match (Filters.Table (F).Pattern.all, Session) then
@@ -721,7 +739,13 @@ package body GNAT.AWK is
 
    function Current_Session return Session_Type is
    begin
+      pragma Warnings (Off);
       return Cur_Session;
+      --  ???The above return statement violates the Ada 2005 rule forbidding
+      --  copying of limited objects (see RM-7.5(2.8/2)). When compiled with
+      --  -gnatg, the compiler gives a warning instead of an error, so we can
+      --  turn it off.
+      pragma Warnings (On);
    end Current_Session;
 
    ---------------------
@@ -730,7 +754,13 @@ package body GNAT.AWK is
 
    function Default_Session return Session_Type is
    begin
+      pragma Warnings (Off);
       return Def_Session;
+      --  ???The above return statement violates the Ada 2005 rule forbidding
+      --  copying of limited objects (see RM-7.5(2.8/2)). When compiled with
+      --  -gnatg, the compiler gives a warning instead of an error, so we can
+      --  turn it off.
+      pragma Warnings (On);
    end Default_Session;
 
    --------------------
@@ -739,46 +769,63 @@ package body GNAT.AWK is
 
    function Discrete_Field
      (Rank    : Count;
-      Session : Session_Type := Current_Session)
-      return    Discrete
+      Session : Session_Type) return Discrete
    is
    begin
       return Discrete'Value (Field (Rank, Session));
    end Discrete_Field;
 
+   function Discrete_Field_Current_Session
+     (Rank    : Count) return Discrete is
+      function Do_It is new Discrete_Field (Discrete);
+   begin
+      return Do_It (Rank, Cur_Session);
+   end Discrete_Field_Current_Session;
+
    -----------------
    -- End_Of_Data --
    -----------------
 
    function End_Of_Data
-     (Session : Session_Type := Current_Session)
-      return    Boolean
+     (Session : Session_Type) return Boolean
    is
    begin
       return Session.Data.File_Index = File_Table.Last (Session.Data.Files)
         and then End_Of_File (Session);
    end End_Of_Data;
 
+   function End_Of_Data
+     return Boolean
+   is
+   begin
+      return End_Of_Data (Cur_Session);
+   end End_Of_Data;
+
    -----------------
    -- End_Of_File --
    -----------------
 
    function End_Of_File
-     (Session : Session_Type := Current_Session)
-      return    Boolean
+     (Session : Session_Type) return Boolean
    is
    begin
       return Text_IO.End_Of_File (Session.Data.Current_File);
    end End_Of_File;
 
+   function End_Of_File
+     return Boolean
+   is
+   begin
+      return End_Of_File (Cur_Session);
+   end End_Of_File;
+
    -----------
    -- Field --
    -----------
 
    function Field
      (Rank    : Count;
-      Session : Session_Type := Current_Session)
-      return    String
+      Session : Session_Type) return String
    is
       Fields : Field_Table.Instance renames Session.Data.Fields;
 
@@ -791,7 +838,7 @@ package body GNAT.AWK is
 
       elsif Rank = 0 then
 
-         --  Returns the whole line, this is what $0 does under Session_Type.
+         --  Returns the whole line, this is what $0 does under Session_Type
 
          return To_String (Session.Data.Current_Line);
 
@@ -803,9 +850,15 @@ package body GNAT.AWK is
    end Field;
 
    function Field
+     (Rank    : Count) return String
+   is
+   begin
+      return Field (Rank, Cur_Session);
+   end Field;
+
+   function Field
      (Rank    : Count;
-      Session : Session_Type := Current_Session)
-      return    Integer
+      Session : Session_Type) return Integer
    is
    begin
       return Integer'Value (Field (Rank, Session));
@@ -820,9 +873,15 @@ package body GNAT.AWK is
    end Field;
 
    function Field
+     (Rank    : Count) return Integer
+   is
+   begin
+      return Field (Rank, Cur_Session);
+   end Field;
+
+   function Field
      (Rank    : Count;
-      Session : Session_Type := Current_Session)
-      return    Float
+      Session : Session_Type) return Float
    is
    begin
       return Float'Value (Field (Rank, Session));
@@ -836,13 +895,19 @@ package body GNAT.AWK is
             Session);
    end Field;
 
+   function Field
+     (Rank    : Count) return Float
+   is
+   begin
+      return Field (Rank, Cur_Session);
+   end Field;
+
    ----------
    -- File --
    ----------
 
    function File
-     (Session : Session_Type := Current_Session)
-      return    String
+     (Session : Session_Type) return String
    is
       Files : File_Table.Instance renames Session.Data.Files;
 
@@ -854,6 +919,13 @@ package body GNAT.AWK is
       end if;
    end File;
 
+   function File
+     return String
+   is
+   begin
+      return File (Cur_Session);
+   end File;
+
    --------------------
    -- For_Every_Line --
    --------------------
@@ -862,10 +934,9 @@ package body GNAT.AWK is
      (Separators : String        := Use_Current;
       Filename   : String        := Use_Current;
       Callbacks  : Callback_Mode := None;
-      Session    : Session_Type  := Current_Session)
+      Session    : Session_Type)
    is
-      Filter_Active : Boolean;
-      Quit          : Boolean;
+      Quit : Boolean;
 
    begin
       Open (Separators, Filename, Session);
@@ -875,7 +946,12 @@ package body GNAT.AWK is
          Split_Line (Session);
 
          if Callbacks in Only .. Pass_Through then
-            Filter_Active := Apply_Filters (Session);
+            declare
+               Discard : Boolean;
+               pragma Unreferenced (Discard);
+            begin
+               Discard := Apply_Filters (Session);
+            end;
          end if;
 
          if Callbacks /= Only then
@@ -888,13 +964,23 @@ package body GNAT.AWK is
       Close (Session);
    end For_Every_Line;
 
+   procedure For_Every_Line_Current_Session
+     (Separators : String        := Use_Current;
+      Filename   : String        := Use_Current;
+      Callbacks  : Callback_Mode := None)
+   is
+      procedure Do_It is new For_Every_Line (Action);
+   begin
+      Do_It (Separators, Filename, Callbacks, Cur_Session);
+   end For_Every_Line_Current_Session;
+
    --------------
    -- Get_Line --
    --------------
 
    procedure Get_Line
      (Callbacks : Callback_Mode := None;
-      Session   : Session_Type := Current_Session)
+      Session   : Session_Type)
    is
       Filter_Active : Boolean;
 
@@ -907,67 +993,103 @@ package body GNAT.AWK is
          Read_Line (Session);
          Split_Line (Session);
 
-         if Callbacks in Only .. Pass_Through then
-            Filter_Active := Apply_Filters (Session);
-         end if;
+         case Callbacks is
 
-         exit when Callbacks = None
-           or else Callbacks = Pass_Through
-           or else (Callbacks = Only and then not Filter_Active);
+            when None =>
+               exit;
 
+            when Only =>
+               Filter_Active := Apply_Filters (Session);
+               exit when not Filter_Active;
+
+            when Pass_Through =>
+               Filter_Active := Apply_Filters (Session);
+               exit;
+
+         end case;
       end loop;
    end Get_Line;
 
+   procedure Get_Line
+     (Callbacks : Callback_Mode := None)
+   is
+   begin
+      Get_Line (Callbacks, Cur_Session);
+   end Get_Line;
+
    ----------------------
    -- Number_Of_Fields --
    ----------------------
 
    function Number_Of_Fields
-     (Session : Session_Type := Current_Session)
-      return    Count
+     (Session : Session_Type) return Count
    is
    begin
       return Count (Field_Table.Last (Session.Data.Fields));
    end Number_Of_Fields;
 
+   function Number_Of_Fields
+     return Count
+   is
+   begin
+      return Number_Of_Fields (Cur_Session);
+   end Number_Of_Fields;
+
    --------------------------
    -- Number_Of_File_Lines --
    --------------------------
 
    function Number_Of_File_Lines
-     (Session : Session_Type := Current_Session)
-      return    Count
+     (Session : Session_Type) return Count
    is
    begin
       return Count (Session.Data.FNR);
    end Number_Of_File_Lines;
 
+   function Number_Of_File_Lines
+     return Count
+   is
+   begin
+      return Number_Of_File_Lines (Cur_Session);
+   end Number_Of_File_Lines;
+
    ---------------------
    -- Number_Of_Files --
    ---------------------
 
    function Number_Of_Files
-     (Session : Session_Type := Current_Session)
-      return    Natural
+     (Session : Session_Type) return Natural
    is
       Files : File_Table.Instance renames Session.Data.Files;
-
    begin
       return File_Table.Last (Files);
    end Number_Of_Files;
 
+   function Number_Of_Files
+     return Natural
+   is
+   begin
+      return Number_Of_Files (Cur_Session);
+   end Number_Of_Files;
+
    ---------------------
    -- Number_Of_Lines --
    ---------------------
 
    function Number_Of_Lines
-     (Session : Session_Type := Current_Session)
-      return    Count
+     (Session : Session_Type) return Count
    is
    begin
       return Count (Session.Data.NR);
    end Number_Of_Lines;
 
+   function Number_Of_Lines
+     return Count
+   is
+   begin
+      return Number_Of_Lines (Cur_Session);
+   end Number_Of_Lines;
+
    ----------
    -- Open --
    ----------
@@ -975,7 +1097,7 @@ package body GNAT.AWK is
    procedure Open
      (Separators : String       := Use_Current;
       Filename   : String       := Use_Current;
-      Session    : Session_Type := Current_Session)
+      Session    : Session_Type)
    is
    begin
       if Text_IO.Is_Open (Session.Data.Current_File) then
@@ -998,12 +1120,20 @@ package body GNAT.AWK is
          raise File_Error;
    end Open;
 
+   procedure Open
+     (Separators : String       := Use_Current;
+      Filename   : String       := Use_Current)
+   is
+   begin
+      Open (Separators, Filename, Cur_Session);
+   end Open;
+
    --------------------
    -- Open_Next_File --
    --------------------
 
    procedure Open_Next_File
-     (Session : Session_Type := Current_Session)
+     (Session : Session_Type)
    is
       Files : File_Table.Instance renames Session.Data.Files;
 
@@ -1033,9 +1163,11 @@ package body GNAT.AWK is
    procedure Parse
      (Separators : String       := Use_Current;
       Filename   : String       := Use_Current;
-      Session    : Session_Type := Current_Session)
+      Session    : Session_Type)
    is
       Filter_Active : Boolean;
+      pragma Unreferenced (Filter_Active);
+
    begin
       Open (Separators, Filename, Session);
 
@@ -1047,6 +1179,14 @@ package body GNAT.AWK is
       Close (Session);
    end Parse;
 
+   procedure Parse
+     (Separators : String       := Use_Current;
+      Filename   : String       := Use_Current)
+   is
+   begin
+      Parse (Separators, Filename, Cur_Session);
+   end Parse;
+
    ---------------------
    -- Raise_With_Info --
    ---------------------
@@ -1057,7 +1197,7 @@ package body GNAT.AWK is
       Session : Session_Type)
    is
       function Filename return String;
-      --  Returns current filename and "??" if the informations is not
+      --  Returns current filename and "??" if this information is not
       --  available.
 
       function Line return String;
@@ -1069,7 +1209,6 @@ package body GNAT.AWK is
 
       function Filename return String is
          File : constant String := AWK.File (Session);
-
       begin
          if File = "" then
             return "??";
@@ -1084,7 +1223,6 @@ package body GNAT.AWK is
 
       function Line return String is
          L : constant String := Natural'Image (Session.Data.FNR);
-
       begin
          return L (2 .. L'Last);
       end Line;
@@ -1111,6 +1249,10 @@ package body GNAT.AWK is
       NR  : Natural renames Session.Data.NR;
       FNR : Natural renames Session.Data.FNR;
 
+      ---------------
+      -- Read_Line --
+      ---------------
+
       function Read_Line return String is
          Buffer : String (1 .. 1_024);
          Last   : Natural;
@@ -1147,7 +1289,7 @@ package body GNAT.AWK is
      (Field   : Count;
       Pattern : String;
       Action  : Action_Callback;
-      Session : Session_Type := Current_Session)
+      Session : Session_Type)
    is
       Filters   : Pattern_Action_Table.Instance renames Session.Data.Filters;
       U_Pattern : constant Unbounded_String := To_Unbounded_String (Pattern);
@@ -1162,13 +1304,22 @@ package body GNAT.AWK is
 
    procedure Register
      (Field   : Count;
+      Pattern : String;
+      Action  : Action_Callback)
+   is
+   begin
+      Register (Field, Pattern, Action, Cur_Session);
+   end Register;
+
+   procedure Register
+     (Field   : Count;
       Pattern : GNAT.Regpat.Pattern_Matcher;
       Action  : Action_Callback;
-      Session : Session_Type := Current_Session)
+      Session : Session_Type)
    is
       Filters : Pattern_Action_Table.Instance renames Session.Data.Filters;
 
-      A_Pattern : Patterns.Pattern_Matcher_Access :=
+      A_Pattern : constant Patterns.Pattern_Matcher_Access :=
                     new Regpat.Pattern_Matcher'(Pattern);
    begin
       Pattern_Action_Table.Increment_Last (Filters);
@@ -1181,12 +1332,21 @@ package body GNAT.AWK is
    procedure Register
      (Field   : Count;
       Pattern : GNAT.Regpat.Pattern_Matcher;
+      Action  : Action_Callback)
+   is
+   begin
+      Register (Field, Pattern, Action, Cur_Session);
+   end Register;
+
+   procedure Register
+     (Field   : Count;
+      Pattern : GNAT.Regpat.Pattern_Matcher;
       Action  : Match_Action_Callback;
-      Session : Session_Type := Current_Session)
+      Session : Session_Type)
    is
       Filters : Pattern_Action_Table.Instance renames Session.Data.Filters;
 
-      A_Pattern : Patterns.Pattern_Matcher_Access :=
+      A_Pattern : constant Patterns.Pattern_Matcher_Access :=
                     new Regpat.Pattern_Matcher'(Pattern);
    begin
       Pattern_Action_Table.Increment_Last (Filters);
@@ -1197,9 +1357,18 @@ package body GNAT.AWK is
    end Register;
 
    procedure Register
+     (Field   : Count;
+      Pattern : GNAT.Regpat.Pattern_Matcher;
+      Action  : Match_Action_Callback)
+   is
+   begin
+      Register (Field, Pattern, Action, Cur_Session);
+   end Register;
+
+   procedure Register
      (Pattern : Pattern_Callback;
       Action  : Action_Callback;
-      Session : Session_Type := Current_Session)
+      Session : Session_Type)
    is
       Filters : Pattern_Action_Table.Instance renames Session.Data.Filters;
 
@@ -1212,13 +1381,28 @@ package body GNAT.AWK is
    end Register;
 
    procedure Register
+     (Pattern : Pattern_Callback;
+      Action  : Action_Callback)
+   is
+   begin
+      Register (Pattern, Action, Cur_Session);
+   end Register;
+
+   procedure Register
      (Action  : Action_Callback;
-      Session : Session_Type := Current_Session)
+      Session : Session_Type)
    is
    begin
       Register (Always_True'Access, Action, Session);
    end Register;
 
+   procedure Register
+     (Action  : Action_Callback)
+   is
+   begin
+      Register (Action, Cur_Session);
+   end Register;
+
    -----------------
    -- Set_Current --
    -----------------
@@ -1234,7 +1418,7 @@ package body GNAT.AWK is
 
    procedure Set_Field_Separators
      (Separators : String       := Default_Separators;
-      Session    : Session_Type := Current_Session)
+      Session    : Session_Type)
    is
    begin
       Free (Session.Data.Separators);
@@ -1250,14 +1434,21 @@ package body GNAT.AWK is
       end if;
    end Set_Field_Separators;
 
+   procedure Set_Field_Separators
+     (Separators : String       := Default_Separators)
+   is
+   begin
+      Set_Field_Separators (Separators, Cur_Session);
+   end Set_Field_Separators;
+
    ----------------------
    -- Set_Field_Widths --
    ----------------------
 
    procedure Set_Field_Widths
      (Field_Widths : Widths_Set;
-      Session      : Session_Type := Current_Session) is
-
+      Session      : Session_Type)
+   is
    begin
       Free (Session.Data.Separators);
 
@@ -1272,19 +1463,42 @@ package body GNAT.AWK is
       end if;
    end Set_Field_Widths;
 
+   procedure Set_Field_Widths
+     (Field_Widths : Widths_Set)
+   is
+   begin
+      Set_Field_Widths (Field_Widths, Cur_Session);
+   end Set_Field_Widths;
+
    ----------------
    -- Split_Line --
    ----------------
 
    procedure Split_Line (Session : Session_Type) is
       Fields : Field_Table.Instance renames Session.Data.Fields;
-
    begin
       Field_Table.Init (Fields);
-
       Split.Current_Line (Session.Data.Separators.all, Session);
    end Split_Line;
 
+   -------------
+   -- Get_Def --
+   -------------
+
+   function Get_Def return Session_Data_Access is
+   begin
+      return Def_Session.Data;
+   end Get_Def;
+
+   -------------
+   -- Set_Cur --
+   -------------
+
+   procedure Set_Cur is
+   begin
+      Cur_Session.Data := Def_Session.Data;
+   end Set_Cur;
+
 begin
    --  We have declared two sessions but both should share the same data.
    --  The current session must point to the default session as its initial