http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45866

           Summary: std::ratio_add, ratio_sub, ratio_multiply,
                    ratio_divide do not have num and den members.
           Product: gcc
           Version: 4.5.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: kal...@gmail.com


The latest C++ draft (which I think is n3126) says this about ratio_add:

"The type ratio_add<R1, R2> shall be a synonym for ratio<T1, T2> where T1 has
the value R1::num * R2::den + R2::num * R1::den and T2 has the value R1::den *
R2::den."

The current implementation in libstdc++ is:

  template<typename _R1, typename _R2>
    struct ratio_add
    {
    private:
      static const intmax_t __gcd =
        __static_gcd<_R1::den, _R2::den>::value;

    public:
      typedef ratio<
        __safe_add<
          __safe_multiply<_R1::num, (_R2::den / __gcd)>::value,
          __safe_multiply<_R2::num, (_R1::den / __gcd)>::value>::value,
        __safe_multiply<_R1::den, (_R2::den / __gcd)>::value> type;
    };

Which places the result in a nested type. I interpret the wording of the
standard to mean that ratio_add<R1, R2> should have the static members num and
den.

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