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Editing: fixnum.h
#ifndef RBIMPL_ARITHMETIC_FIXNUM_H /*-*-C++-*-vi:se ft=cpp:*/ #define RBIMPL_ARITHMETIC_FIXNUM_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 Handling of integers formerly known as Fixnums. */ #include "ruby/backward/2/limits.h" #define FIXABLE RB_FIXABLE /**< @old{RB_FIXABLE} */ #define FIXNUM_MAX RUBY_FIXNUM_MAX /**< @old{RUBY_FIXNUM_MAX} */ #define FIXNUM_MIN RUBY_FIXNUM_MIN /**< @old{RUBY_FIXNUM_MIN} */ #define NEGFIXABLE RB_NEGFIXABLE /**< @old{RB_NEGFIXABLE} */ #define POSFIXABLE RB_POSFIXABLE /**< @old{RB_POSFIXABLE} */ /** * Checks if the passed value is in range of fixnum, assuming it is a positive * number. Can sometimes be useful for C's unsigned integer types. * * @internal * * FIXABLE can be applied to anything, from double to intmax_t. The problem is * double. On a 64bit system RUBY_FIXNUM_MAX is 4,611,686,018,427,387,903, * which is not representable by a double. The nearest value that a double can * represent is 4,611,686,018,427,387,904, which is not fixable. The * seemingly-strange "< FIXNUM_MAX + 1" expression below is due to this. */ #define RB_POSFIXABLE(_) ((_) < RUBY_FIXNUM_MAX + 1) /** * Checks if the passed value is in range of fixnum, assuming it is a negative * number. This is an implementation of #RB_FIXABLE. Rarely used stand alone. */ #define RB_NEGFIXABLE(_) ((_) >= RUBY_FIXNUM_MIN) /** Checks if the passed value is in range of fixnum */ #define RB_FIXABLE(_) (RB_POSFIXABLE(_) && RB_NEGFIXABLE(_)) /** Maximum possible value that a fixnum can represent. */ #define RUBY_FIXNUM_MAX (LONG_MAX / 2) /** Minimum possible value that a fixnum can represent. */ #define RUBY_FIXNUM_MIN (LONG_MIN / 2) #endif /* RBIMPL_ARITHMETIC_FIXNUM_H */
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