gcc/ada/libgnat/s-strops.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
   4 --                                                                          --
   5 --                    S Y S T E M . S T R I N G _ O P S                     --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2017, 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 --  NOTE: This package is obsolescent. It is no longer used by the compiler
  33 --  which now generates concatenation inline. It is retained only because
  34 --  it may be used during bootstrapping using old versions of the compiler.
  35
  36 pragma Compiler_Unit_Warning;
  37
  38 package body System.String_Ops is
  39
  40    ----------------
  41    -- Str_Concat --
  42    ----------------
  43
  44    function Str_Concat (X, Y : String) return String is
  45    begin
  46       if X'Length = 0 then
  47          return Y;
  48
  49       else
  50          declare
  51             L : constant Natural := X'Length + Y'Length;
  52             R : String (X'First .. X'First + L - 1);
  53
  54          begin
  55             R (X'Range) := X;
  56             R (X'First + X'Length .. R'Last) := Y;
  57             return R;
  58          end;
  59       end if;
  60    end Str_Concat;
  61
  62    -------------------
  63    -- Str_Concat_CC --
  64    -------------------
  65
  66    function Str_Concat_CC (X, Y : Character) return String is
  67       R : String (1 .. 2);
  68
  69    begin
  70       R (1) := X;
  71       R (2) := Y;
  72       return R;
  73    end Str_Concat_CC;
  74
  75    -------------------
  76    -- Str_Concat_CS --
  77    -------------------
  78
  79    function Str_Concat_CS (X : Character; Y : String) return String is
  80       R : String (1 .. Y'Length + 1);
  81
  82    begin
  83       R (1) := X;
  84       R (2 .. R'Last) := Y;
  85       return R;
  86    end Str_Concat_CS;
  87
  88    -------------------
  89    -- Str_Concat_SC --
  90    -------------------
  91
  92    function Str_Concat_SC (X : String; Y : Character) return String is
  93    begin
  94       if X'Length = 0 then
  95          return (1 => Y);
  96
  97       else
  98          declare
  99             R : String (X'First .. X'Last + 1);
 100
 101          begin
 102             R (X'Range) := X;
 103             R (R'Last) := Y;
 104             return R;
 105          end;
 106       end if;
 107    end Str_Concat_SC;
 108
 109 end System.String_Ops;