View Javadoc

1   ////////////////////////////////////////////////////////////////////////////////
2   // MillScript: an Open Spice interpreter and batch website creation tool
3   // Copyright (C) 2001-2004 Open World Ltd
4   // Copyright (C) 2005 Kevin Rogers
5   //
6   // This file is part of MillScript.
7   //
8   // MillScript is free software; you can redistribute it and/or modify it under
9   // the terms of the GNU General Public License as published by the Free
10  // Software Foundation; either version 2 of the License, or (at your option)
11  // any later version.
12  //
13  // MillScript is distributed in the hope that it will be useful, but WITHOUT
14  // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15  // FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
16  // more details.
17  //
18  // You should have received a copy of the GNU General Public License along with
19  // MillScript; if not, write to the Free Software Foundation, Inc., 59 Temple
20  // Place, Suite 330, Boston, MA  02111-1307  USA
21  ////////////////////////////////////////////////////////////////////////////////
22  package org.millscript.millscript.action;
23  
24  import org.millscript.commons.util.list.IArrayList;
25  import org.millscript.millscript.vm.Machine;
26  
27  /**
28   * This class represents the action for a list expression.
29   *
30   * @see org.millscript.millscript.expr.ListExpr
31   * @see org.millscript.millscript.syntax.ListSyntax
32   */
33  public final class ListAction extends Action {
34  
35      /**
36       * The action that generate values for the list.
37       */
38      private Action body;
39  
40      /**
41       * Constructs a new list action, to make a list containing the values
42       * generated by the specified body action.
43       *
44       * @param a the action generating results for the list
45       */
46      public ListAction( final Action a ) {
47          body = a;
48      }
49  
50      /**
51       * @see org.millscript.millscript.action.Action#action(org.millscript.millscript.vm.Machine)
52       */
53      @Override
54      public void action( final Machine mc ) {
55          // Store the number of values on the stack, before generating the
56          // values for the list
57          int n = mc.getCount();
58          // Generate the results for the list
59          body.act( mc );
60          // Calculate how many results there are, i.e. the size of the list, and
61          // get an array of that number of values off the stack
62          mc.pushObject(
63              new IArrayList< Object >(
64  	            mc.popArgsArray( mc.getCount() - n ),
65                  true
66              )
67          );
68      }
69  
70  }