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std::ratio_equal

性病：：比率[医]平等

Defined in header ​​
template< class R1, class R2 > struct ratio_equal : std::integral_constant;​​

如果r1和r2相等，则提供成员常量。value平等true.否则，value是false...

辅助变量模板

template< class R1, class R2 > inline constexpr bool ratio_equal_v = ratio_equal::value;​(since C++17)

继承自STD：积分[医]常量

成员常数

value statictrue if R1::num == R2::num && R1::den == R2::den , false otherwise (public static member constant)

成员函数

operator boolconverts the object to bool, returns value (public member function)
operator() (C++14)returns value (public member function)

成员类型

TypeDefinition
value_typebool
typestd::integral_constant<bool, value>

可能的实施

模板<类R1，类R2>结构比[医]平等：公共科技促进发展：：积分[医]常数<bool，R1：：num=r2：：num&&&r1：：den=r2：：den>{}；

*。

例

二次

#include <iostream>
#include <ratio>
 
int main()
{
    if(std::ratio_equal<std::ratio<2,3>, std::ratio<4,6>>::value) {
        std::cout << "2/3 == 4/6\n";
    } else {
        std::cout << "2/3 != 4/6\n";
    }
}

二次

产出：

二次

2/3 == 4/6

二次

另见

二次

*。

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