std::ratio_equal (3) - Linux Manuals

std::ratio_equal: std::ratio_equal

NAME

std::ratio_equal - std::ratio_equal

Synopsis

Defined in header <ratio>
template< class R1, class R2 > (since C++11)
struct ratio_equal : std::integral_constant;

If the ratios R1 and R2 are equal, provides the member constant value equal true. Otherwise, value is false.

Helper variable template

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

Inherited from std::integral_constant

Member constants

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

Member functions

              converts the object to bool, returns value
operator bool (public member function)

operator() returns value
              (public member function)
(C++14)

Member types

Type Definition
value_type bool
type std::integral_constant<bool, value>

Possible implementation

  template< class R1, class R2 >
  struct ratio_equal : public std::integral_constant <
                                   bool,
                                   R1::num == R2::num && R1::den == R2::den
                              > {};

Example

// Run this code

  #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";
      }
  }

Output:

  2/3 == 4/6