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-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc
-- This file is part of VESTs (Vhdl tESTs).
-- VESTs is free software; you can redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the
-- Free Software Foundation; either version 2 of the License, or (at
-- your option) any later version.
-- VESTs is distributed in the hope that it will be useful, but WITHOUT
-- 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
-- along with VESTs; if not, write to the Free Software Foundation,
-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-- ---------------------------------------------------------------------
--
-- $Id: ch_17_fg_17_07.vhd,v 1.2 2001-10-26 16:29:36 paw Exp $
-- $Revision: 1.2 $
--
-- ---------------------------------------------------------------------
entity fg_17_07 is
end entity fg_17_07;
----------------------------------------------------------------
architecture test of fg_17_07 is
signal s : bit_vector(0 to 3);
begin
process is
type value_cell;
type value_ptr is access value_cell;
type value_cell is record
value : bit_vector(0 to 3);
next_cell : value_ptr;
end record value_cell;
variable value_list, current_cell : value_ptr;
variable search_value : bit_vector(0 to 3);
begin
value_list := new value_cell'( B"1000", value_list );
value_list := new value_cell'( B"0010", value_list );
value_list := new value_cell'( B"0000", value_list );
search_value := B"0010";
-- code from book:
current_cell := value_list;
while current_cell /= null
and current_cell.value /= search_value loop
current_cell := current_cell.next_cell;
end loop;
assert current_cell /= null
report "search for value failed";
-- end of code from book
search_value := B"1111";
current_cell := value_list;
while current_cell /= null
and current_cell.value /= search_value loop
current_cell := current_cell.next_cell;
end loop;
assert current_cell /= null
report "search for value failed";
wait;
end process;
end architecture test;
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