01: /*
02: * float_sign.java
03: *
04: * Copyright (C) 2004 Peter Graves
05: * $Id: float_sign.java,v 1.1 2004/06/06 19:31:53 piso 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: public final class float_sign extends Primitive {
25: private float_sign() {
26: super ("float-sign", "float-1 &optional float-2");
27: }
28:
29: public LispObject execute(LispObject arg) throws ConditionThrowable {
30: try {
31: double d = ((LispFloat) arg).value;
32: long bits = Double.doubleToRawLongBits(d);
33: return bits < 0 ? LispFloat.MINUS_ONE : LispFloat.ONE;
34: } catch (ClassCastException e) {
35: return signal(new TypeError(arg, Symbol.FLOAT));
36: }
37: }
38:
39: public LispObject execute(LispObject first, LispObject second)
40: throws ConditionThrowable {
41: double d1, d2;
42: try {
43: d1 = ((LispFloat) first).value;
44: } catch (ClassCastException e) {
45: return signal(new TypeError(first, Symbol.FLOAT));
46: }
47: try {
48: d2 = Math.abs(((LispFloat) second).value);
49: } catch (ClassCastException e) {
50: return signal(new TypeError(second, Symbol.FLOAT));
51: }
52: long bits = Double.doubleToRawLongBits(d1);
53: return bits < 0 ? new LispFloat(-d2) : new LispFloat(d2);
54: }
55:
56: private static final Primitive FLOAT_SIGN = new float_sign();
57: }
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