1 2-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc 3 4-- This file is part of VESTs (Vhdl tESTs). 5 6-- VESTs is free software; you can redistribute it and/or modify it 7-- under the terms of the GNU General Public License as published by the 8-- Free Software Foundation; either version 2 of the License, or (at 9-- your option) any later version. 10 11-- VESTs is distributed in the hope that it will be useful, but WITHOUT 12-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13-- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14-- for more details. 15 16-- You should have received a copy of the GNU General Public License 17-- along with VESTs; if not, write to the Free Software Foundation, 18-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 20-- --------------------------------------------------------------------- 21-- 22-- $Id: ch_17_ch_17_09.vhd,v 1.2 2001-10-26 16:29:36 paw Exp $ 23-- $Revision: 1.2 $ 24-- 25-- --------------------------------------------------------------------- 26 27entity ch_17_09 is 28 29end entity ch_17_09; 30 31 32---------------------------------------------------------------- 33 34 35architecture test of ch_17_09 is 36 37begin 38 39 process is 40 41 type value_cell; 42 43 type value_ptr is access value_cell; 44 45 type value_cell is record 46 value : bit_vector(0 to 3); 47 next_cell : value_ptr; 48 end record value_cell; 49 50 variable value_list, cell_to_be_deleted : value_ptr; 51 52 begin 53 value_list := new value_cell'( B"1000", value_list ); 54 value_list := new value_cell'( B"0010", value_list ); 55 value_list := new value_cell'( B"0000", value_list ); 56 57 -- code from book: 58 59 cell_to_be_deleted := value_list; 60 value_list := value_list.next_cell; 61 deallocate(cell_to_be_deleted); 62 63 while value_list /= null loop 64 cell_to_be_deleted := value_list; 65 value_list := value_list.next_cell; 66 deallocate(cell_to_be_deleted); 67 end loop; 68 69 -- end of code from book 70 71 wait; 72 end process; 73 74end architecture test; 75