< cpp‎ | numeric‎ | ratio
Defined in header <ratio>
template< class R1, class R2 >
struct ratio_less : std::integral_constant;

If the ratio R1 is less than the ratio R2, provides the member constant value equal true. Otherwise, value is false.


[edit] Helper variable template

template< class R1, class R2 >
constexpr bool ratio_less_v = ratio_less<R1, R2>::value;
(since C++17)

Inherited from std::integral_constant

Member constants

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

Member functions

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

Member types

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

[edit] Example

#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

[edit] See also

(library fundamentals TS)
variable template alias of std::ratio_less::value
(variable template)