01: /*
02: * logtest.java
03: *
04: * Copyright (C) 2003 Peter Graves
05: * $Id: logtest.java,v 1.6 2003/11/15 11:03:33 beedlem Exp $
06: *
07: * This program is free software; you can redistribute it and/or
08: * modify it under the terms of the GNU General Public License
09: * as published by the Free Software Foundation; either version 2
10: * of the License, or (at your option) any later version.
11: *
12: * This program is distributed in the hope that it will be useful,
13: * but WITHOUT ANY WARRANTY; without even the implied warranty of
14: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15: * GNU General Public License for more details.
16: *
17: * You should have received a copy of the GNU General Public License
18: * along with this program; if not, write to the Free Software
19: * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20: */
21:
22: package org.armedbear.lisp;
23:
24: import java.math.BigInteger;
25:
26: // ### logtest
27: // logtest integer-1 integer-2 => generalized-boolean
28: // (logtest x y) == (not (zerop (logand x y)))
29: public final class logtest extends Primitive2 {
30: private logtest() {
31: super ("logtest");
32: }
33:
34: public LispObject execute(LispObject first, LispObject second)
35: throws ConditionThrowable {
36: if (first instanceof Fixnum && second instanceof Fixnum) {
37: return (((Fixnum) first).getValue() & ((Fixnum) second)
38: .getValue()) == 0 ? NIL : T;
39: } else {
40: BigInteger n1, n2;
41: if (first instanceof Fixnum)
42: n1 = ((Fixnum) first).getBigInteger();
43: else if (first instanceof Bignum)
44: n1 = ((Bignum) first).getValue();
45: else
46: throw new ConditionThrowable(new TypeError(first,
47: "integer"));
48: if (second instanceof Fixnum)
49: n2 = ((Fixnum) second).getBigInteger();
50: else if (second instanceof Bignum)
51: n2 = ((Bignum) second).getValue();
52: else
53: throw new ConditionThrowable(new TypeError(second,
54: "integer"));
55: return n1.and(n2).signum() == 0 ? NIL : T;
56: }
57: }
58:
59: private static final logtest LOGTEST = new logtest();
60: }
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