diff options
Diffstat (limited to 'kjs/simple_number.h')
-rw-r--r-- | kjs/simple_number.h | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/kjs/simple_number.h b/kjs/simple_number.h new file mode 100644 index 000000000..1f5830dff --- /dev/null +++ b/kjs/simple_number.h @@ -0,0 +1,52 @@ +// -*- c-basic-offset: 2 -*- +/* + * This file is part of the KDE libraries + * Copyright (C) 2003 Apple Computer, Inc + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public License + * along with this library; see the file COPYING.LIB. If not, write to + * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + * Boston, MA 02110-1301, USA. + * + */ + +#ifndef _KJS_SIMPLE_NUMBER_H_ +#define _KJS_SIMPLE_NUMBER_H_ + +#include <math.h> +#include <string.h> + +#define IS_NEGATIVE_ZERO(num) (num == 0.0 && !memcmp(&num, &SimpleNumber::negZero, sizeof(double))) + +namespace KJS { + class ValueImp; + + class SimpleNumber { + public: + enum { tag = 1, shift = 2, mask = (1 << shift) - 1, sign = 1L << (sizeof(long) * 8 - 1 ), max = (1L << ((sizeof(long) * 8 - 1) - shift)) - 1, min = -max - 1, imax = (1L << ((sizeof(int) * 8 - 1) - shift)) - 1, imin = -imax - 1 }; + + static inline bool is(const ValueImp *imp) { return ((long)imp & mask) == tag; } + static inline long value(const ValueImp *imp) { return ((long)imp >> shift) | (((long)imp & sign) ? ~max : 0); } + + static inline bool fits(int i) { return i <= imax && i >= imin; } + static inline bool fits(unsigned i) { return i <= (unsigned)max; } + static inline bool fits(long i) { return i <= max && i >= min; } + static inline bool fits(unsigned long i) { return i <= (unsigned)max; } + static inline bool fits(double d) { return d >= min && d <= max && d == (double)(long)d && !IS_NEGATIVE_ZERO(d); } + static inline ValueImp *make(long i) { return (ValueImp *)((i << shift) | tag); } + + static double negZero; + }; +} + +#endif |