gcc/ada/a-slcain.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT LIBRARY COMPONENTS                          --
   4 --                                                                          --
   5 --                    ADA.STRINGS.LESS_CASE_INSENSITIVE                     --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 2004-2006, 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 2,  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 COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- This unit was originally developed by Matthew J Heaney.                  --
  30 ------------------------------------------------------------------------------
  31
  32 with Ada.Characters.Handling; use Ada.Characters.Handling;
  33
  34 function Ada.Strings.Less_Case_Insensitive
  35   (Left, Right : String) return Boolean
  36 is
  37    LI : Integer := Left'First;
  38    RI : Integer := Right'First;
  39
  40    LC, RC : Character;
  41
  42 begin
  43    if LI > Left'Last then
  44       return RI <= Right'Last;
  45    end if;
  46
  47    if RI > Right'Last then
  48       return False;
  49    end if;
  50
  51    loop
  52       LC := To_Lower (Left (LI));
  53       RC := To_Lower (Right (RI));
  54
  55       if LC < RC then
  56          return True;
  57       end if;
  58
  59       if LC > RC then
  60          return False;
  61       end if;
  62
  63       if LI = Left'Last then
  64          return RI < Right'Last;
  65       end if;
  66
  67       if RI = Right'Last then
  68          return False;
  69       end if;
  70
  71       LI := LI + 1;
  72       RI := RI + 1;
  73    end loop;
  74 end Ada.Strings.Less_Case_Insensitive;