class template
<ratio>

std::ratio_less

template <class R1, class R2> ratio_less;
Compare ratios for less-than inequality
This type inherits from the appropriate integral_constant type (either true_type or false_type) to signal whether R1 compares less than R2
The resulting type is the same as if ratio_less was defined as:
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template <class R1, class R2>
struct ratio_less : integral_constant < bool, R1::num*R2::den < R2::num*R1::den > {};

A program shall not cause any expression in the above definition to expand to values not representable as an intmax_t.

Template parameters

R1,R2
ratio types to be compared.

Member constants

Inherited from integral_constant:
member constantdefinition
valueeither true or false

Member types

Inherited from integral_constant:
member typedefinition
value_typebool
typeeither true_type or false_type

Example

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// ratio_less example
#include <iostream>
#include <ratio>

int main ()
{
  typedef std::ratio<1,3> one_third;
  typedef std::ratio<1,2> one_half;

  std::cout << "1/3 < 1/2 ? " << std::boolalpha;
  std::cout << std::ratio_less<one_third,one_half>::value << std::endl;

  return 0;
}

Output:
1/3 < 1/2 ? true


See also