01: /*
02: * Jatha - a Common LISP-compatible LISP library in Java.
03: * Copyright (C) 1997-2005 Micheal Scott Hewett
04: *
05: * This library is free software; you can redistribute it and/or
06: * modify it under the terms of the GNU Lesser General Public
07: * License as published by the Free Software Foundation; either
08: * version 2.1 of the License, or (at your option) any later version.
09: *
10: * This library is distributed in the hope that it will be useful,
11: * but WITHOUT ANY WARRANTY; without even the implied warranty of
12: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13: * Lesser General Public License for more details.
14: *
15: * You should have received a copy of the GNU Lesser General Public
16: * License along with this library; if not, write to the Free Software
17: * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18: *
19: *
20: * For further information, please contact Micheal Hewett at
21: * hewett@cs.stanford.edu
22: *
23: */
24:
25: package org.jatha.compile;
26:
27: import java.util.*;
28:
29: import org.jatha.Jatha;
30: import org.jatha.dynatype.*;
31: import org.jatha.machine.*;
32:
33: public class GreaterThanPrimitive extends LispPrimitive {
34: public GreaterThanPrimitive(Jatha lisp) {
35: super (lisp, ">", 2, Long.MAX_VALUE);
36: }
37:
38: public void Execute(SECDMachine machine) {
39: LispValue args = machine.S.pop();
40:
41: if (args == f_lisp.NIL)
42: machine.S.push(f_lisp.T);
43: else {
44: // There should be at least 2 arguments.
45: LispValue prevArg = args.first();
46: args = args.cdr();
47: for (Iterator iterator = args.iterator(); iterator
48: .hasNext();) {
49: LispValue arg = (LispValue) iterator.next();
50: if (prevArg.greaterThan(arg) == f_lisp.NIL) {
51: machine.S.push(f_lisp.NIL);
52: machine.C.pop();
53: return;
54: }
55: prevArg = arg;
56: }
57: machine.S.push(f_lisp.T);
58: }
59:
60: machine.C.pop();
61: }
62:
63: // Unlimited number of evaluated args.
64: public LispValue CompileArgs(LispCompiler compiler,
65: SECDMachine machine, LispValue args, LispValue valueList,
66: LispValue code) throws CompilerException {
67: return compiler.compileArgsLeftToRight(args, valueList, f_lisp
68: .makeCons(machine.LIS, f_lisp.makeCons(args.length(),
69: code)));
70: }
71:
72: }
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