#ifndef RBIMPL_INTERN_RATIONAL_H /*-*-C++-*-vi:se ft=cpp:*/
#define RBIMPL_INTERN_RATIONAL_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 Public APIs related to ::rb_cRational.
*/
#include "ruby/internal/attr/pure.h"
#include "ruby/internal/dllexport.h"
#include "ruby/internal/value.h"
#include "ruby/internal/arithmetic/long.h" /* INT2FIX is here. */
RBIMPL_SYMBOL_EXPORT_BEGIN()
/* rational.c */
/**
* Identical to rb_rational_new(), except it skips argument validations. It is
* thus dangerous for extension libraries. For instance `1/0r` could be
* constructed using this.
*
* @param[in] num Numerator, an instance of ::rb_cInteger.
* @param[in] den Denominator, an instance of ::rb_cInteger.
* @exception rb_eTypeError Either argument is not an Integer.
* @return An instance of ::rb_cRational whose value is `(num/den)r`.
*/
VALUE rb_rational_raw(VALUE num, VALUE den);
/**
* Shorthand of `(x/1)r`. As `x` is already an Integer, it practically
* converts it into a Rational of the identical value.
*
* @param[in] x An instance of ::rb_cInteger.
* @return An instance of ::rb_cRational, whose value is `(x/1)r`.
*/
#define rb_rational_raw1(x) rb_rational_raw((x), INT2FIX(1))
/** @alias{rb_rational_raw} */
#define rb_rational_raw2(x,y) rb_rational_raw((x), (y))
/**
* Constructs a Rational, with reduction. This returns for instance `(2/3)r`
* for `rb_rational_new(INT2NUM(-384), INT2NUM(-576))`.
*
* @param[in] num Numerator, an instance of ::rb_cInteger.
* @param[in] den Denominator, an instance of ::rb_cInteger.
* @exception rb_eZeroDivError `den` is zero.
* @return An instance of ::rb_cRational whose value is `(num/den)r`.
*/
VALUE rb_rational_new(VALUE num, VALUE den);
/**
* Shorthand of `(x/1)r`. As `x` is already an Integer, it practically
* converts it into a Rational of the identical value.
*
* @param[in] x An instance of ::rb_cInteger.
* @return An instance of ::rb_cRational, whose value is `(x/1)r`.
*/
#define rb_rational_new1(x) rb_rational_new((x), INT2FIX(1))
/** @alias{rb_rational_new} */
#define rb_rational_new2(x,y) rb_rational_new((x), (y))
/**
* Converts various values into a Rational. This function accepts:
*
* - Instances of ::rb_cInteger (taken as-is),
* - Instances of ::rb_cRational (taken as-is),
* - Instances of ::rb_cFloat (applies `#to_r`),
* - Instances of ::rb_cComplex (applies `#to_r`),
* - Instances of ::rb_cString (applies `#to_r`),
* - Other objects that respond to `#to_r`.
*
* It (possibly recursively) applies `#to_r` until both sides become either
* Integer or Rational, then divides them.
*
* As a special case, passing ::RUBY_Qundef to `den` is the same as passing
* `RB_INT2NUM(1)`.
*
* @param[in] num Numerator (see above).
* @param[in] den Denominator (see above).
* @exception rb_eTypeError Passed something not described above.
* @exception rb_eFloatDomainError `#to_r` produced Nan/Inf.
* @exception rb_eZeroDivError `#to_r` produced zero for `den`.
* @return An instance of ::rb_cRational whose value is `(num/den)r`.
*
* @internal
*
* This was the implementation of `Kernel#Rational` before, but they diverged.
*/
VALUE rb_Rational(VALUE num, VALUE den);
/**
* Shorthand of `(x/1)r`. It practically converts it into a Rational of the
* identical value.
*
* @param[in] x ::rb_cInteger, ::rb_cRational, or something that responds to
* `#to_r`.
* @return An instance of ::rb_cRational, whose value is `(x/1)r`.
*/
#define rb_Rational1(x) rb_Rational((x), INT2FIX(1))
/** @alias{rb_Rational} */
#define rb_Rational2(x,y) rb_Rational((x), (y))
RBIMPL_ATTR_PURE()
/**
* Queries the numerator of the passed Rational.
*
* @param[in] rat An instance of ::rb_cRational.
* @return Its numerator part, which is an instance of ::rb_cInteger.
*/
VALUE rb_rational_num(VALUE rat);
RBIMPL_ATTR_PURE()
/**
* Queries the denominator of the passed Rational.
*
* @param[in] rat An instance of ::rb_cRational.
* @return Its denominator part, which is an instance of ::rb_cInteger
* greater than or equal to one..
*/
VALUE rb_rational_den(VALUE rat);
/**
* Simplified approximation of a float. It returns a rational `rat` which
* satisfies:
*
* ```
* flt - |prec| <= rat <= flt + |prec|
* ```
*
* ```ruby
* 3.141592.rationalize(0.001) # => (201/64)r
* 3.141592.rationalize(0.01)' # => (22/7)r
* 3.141592.rationalize(0.1)' # => (16/5)r
* 3.141592.rationalize(1)' # => (3/1)r
* ```
*
* @param[in] flt An instance of ::rb_cFloat to rationalise.
* @param[in] prec Another ::rb_cFloat, which is the "precision".
* @return Approximation of `flt`, in ::rb_cRational.
*/
VALUE rb_flt_rationalize_with_prec(VALUE flt, VALUE prec);
/**
* Identical to rb_flt_rationalize_with_prec(), except it auto-detects
* appropriate precision depending on the passed value.
*
* @param[in] flt An instance of ::rb_cFloat to rationalise.
* @return Approximation of `flt`, in ::rb_cRational.
*/
VALUE rb_flt_rationalize(VALUE flt);
RBIMPL_SYMBOL_EXPORT_END()
#endif /* RBIMPL_INTERN_RATIONAL_H */