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Diffstat (limited to 'include/ruby/internal/core/rbignum.h')
| -rw-r--r-- | include/ruby/internal/core/rbignum.h | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/include/ruby/internal/core/rbignum.h b/include/ruby/internal/core/rbignum.h new file mode 100644 index 0000000000..1d31743235 --- /dev/null +++ b/include/ruby/internal/core/rbignum.h @@ -0,0 +1,80 @@ +#ifndef RBIMPL_RBIGNUM_H /*-*-C++-*-vi:se ft=cpp:*/ +#define RBIMPL_RBIGNUM_H +/** + * @file + * @author Ruby developers <ruby-core@ruby-lang.org> + * @copyright This file is a part of the programming language Ruby. + * Permission is hereby granted, to either redistribute and/or + * modify this file, provided that the conditions mentioned in the + * file COPYING are met. Consult the file for details. + * @warning Symbols prefixed with either `RBIMPL` or `rbimpl` are + * implementation details. Don't take them as canon. They could + * rapidly appear then vanish. The name (path) of this header file + * is also an implementation detail. Do not expect it to persist + * at the place it is now. Developers are free to move it anywhere + * anytime at will. + * @note To ruby-core: remember that this header can be possibly + * recursively included from extension libraries written in C++. + * Do not expect for instance `__VA_ARGS__` is always available. + * We assume C99 for ruby itself but we don't assume languages of + * extension libraries. They could be written in C++98. + * @brief Routines to manipulate struct RBignum. + * @note The struct RBignum itself is opaque. + */ +#include "ruby/internal/dllexport.h" +#include "ruby/internal/value.h" +#include "ruby/internal/value_type.h" +#include "ruby/internal/stdbool.h" + +#define RBIGNUM_SIGN rb_big_sign /**< @alias{rb_big_sign} */ + +/** @cond INTERNAL_MACRO */ +#define RBIGNUM_POSITIVE_P RBIGNUM_POSITIVE_P +#define RBIGNUM_NEGATIVE_P RBIGNUM_NEGATIVE_P +/** @endcond */ + +RBIMPL_SYMBOL_EXPORT_BEGIN() +/** + * The "sign" of a bignum. + * + * @param[in] num An object of RBignum. + * @retval 1 It is greater than or equal to zero. + * @retval 0 It is less than zero. + * + * @internal + * + * Implementation wise, unlike fixnums (which are 2's complement), bignums are + * signed magnitude system. Theoretically it could be possible to have + * negative zero instances. But in reality there is no way to create such + * thing. Nobody ever needed that kind of insanity. + */ +int rb_big_sign(VALUE num); +RBIMPL_SYMBOL_EXPORT_END() + +/** + * Checks if the bignum is positive. + * @param[in] b An object of RBignum. + * @retval false `b` is less than zero. + * @retval true Otherwise. + */ +static inline bool +RBIGNUM_POSITIVE_P(VALUE b) +{ + RBIMPL_ASSERT_TYPE(b, RUBY_T_BIGNUM); + return RBIGNUM_SIGN(b); +} + +/** + * Checks if the bignum is negative. + * @param[in] b An object of RBignum. + * @retval true `b` is less than zero. + * @retval false Otherwise. + */ +static inline bool +RBIGNUM_NEGATIVE_P(VALUE b) +{ + RBIMPL_ASSERT_TYPE(b, RUBY_T_BIGNUM); + return ! RBIGNUM_POSITIVE_P(b); +} + +#endif /* RBIMPL_RBIGNUM_H */ |