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std::ratio_less(3) C++ Standard Libary std::ratio_less(3)


std::ratio_less - std::ratio_less


Defined in header <ratio>
template< class R1, class R2 >
struct ratio_less : std::integral_constant<bool, /* see below */> { (since C++11)

If the ratio R1 is less than the ratio R2, 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_less_v = ratio_less<R1, R2>::value;

Inherited from std::integral_constant

Member constants

value true if R1::num * R2::den < R2::num * R1::den, or equivalent expression
[static] that avoids overflow , false otherwise
(public static member constant)

Member functions

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

Member types

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


// Run this code

#include <iostream>
#include <ratio>

int main()
if (std::ratio_less<std::ratio<23,37>, std::ratio<57,90>>::value) {
std::cout << "23/37 < 57/90\n";


23/37 < 57/90

See also