------------------------------------------------------------------------------ -- -- -- GNAT LIBRARY COMPONENTS -- -- -- -- ADA.STRINGS.HASH -- -- -- -- B o d y -- -- -- -- Copyright (C) 2004 Free Software Foundation, Inc. -- -- -- -- This specification is derived from the Ada Reference Manual for use with -- -- GNAT. The copyright notice above, and the license provisions that follow -- -- apply solely to the contents of the part following the private keyword. -- -- -- -- 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- -- -- ware Foundation; either version 2, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- 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. -- -- -- -- As a special exception, if other files instantiate generics from this -- -- unit, or you link this unit with other files to produce an executable, -- -- this unit does not by itself cause the resulting executable to be -- -- covered by the GNU General Public License. This exception does not -- -- however invalidate any other reasons why the executable file might be -- -- covered by the GNU Public License. -- -- -- -- This unit was originally developed by Matthew J Heaney. -- ------------------------------------------------------------------------------ -- Note: source of this algorithm: GNAT.HTable.Hash (g-htable.adb) function Ada.Strings.Hash (Key : String) return Containers.Hash_Type is use Ada.Containers; function Rotate_Left (Value : Hash_Type; Amount : Natural) return Hash_Type; pragma Import (Intrinsic, Rotate_Left); Tmp : Hash_Type; begin Tmp := 0; for J in Key'Range loop Tmp := Rotate_Left (Tmp, 1) + Character'Pos (Key (J)); end loop; return Tmp; end Ada.Strings.Hash;