1 ////////////////////////////////////////////////////////////////////////////////
2 // MillScript: an Open Spice interpreter and batch website creation tool
3 // Copyright (C) 2001-2004 Open World Ltd
4 //
5 // This file is part of MillScript.
6 //
7 // MillScript is free software; you can redistribute it and/or modify it under
8 // the terms of the GNU General Public License as published by the Free
9 // Software Foundation; either version 2 of the License, or (at your option)
10 // any later version.
11 //
12 // MillScript is distributed in the hope that it will be useful, but WITHOUT
13 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 // more details.
16 //
17 // You should have received a copy of the GNU General Public License along with
18 // MillScript; if not, write to the Free Software Foundation, Inc., 59 Temple
19 // Place, Suite 330, Boston, MA 02111-1307 USA
20 ////////////////////////////////////////////////////////////////////////////////
21 package org.millscript.millscript.action;
22
23 import org.millscript.millscript.vm.Machine;
24
25 /**
26 * This class implements the action for a <code>not</code> expression. This
27 * action performs an action that must return a boolean result, and returns the
28 * logical inverse of that result.
29 *
30 * @see org.millscript.millscript.expr.NotExpr
31 * @see org.millscript.millscript.syntax.NotSyntax
32 */
33 public final class NotAction extends Action {
34
35 /**
36 * The predicate action, which we will return the locigal inverse of.
37 */
38 private Action cont;
39
40 /**
41 * Constructs a new not action, on the specified predicate action.
42 *
43 * @param c the predicate action
44 */
45 public NotAction( final Action c ) {
46 this.cont = c;
47 }
48
49 /**
50 * @see org.millscript.millscript.action.Action#action(org.millscript.millscript.vm.Machine)
51 */
52 @Override
53 public void action( final Machine mc ) {
54 mc.pushObject( cont.predAct( mc ) ? Boolean.FALSE : Boolean.TRUE );
55 }
56
57 }