The TR1 Tuple provides 2 helper traits, for compile time access to the tuple size, and the element types.
Requires: T is any fusion sequence type, including tuple.
Type: MPL Integral Constant
Value: The number of elements in the sequence. Equivalent to result_of::size<T>::type.
Requires: T is any fusion sequence type, including tuple. 0 <= I < N or the program is ill formed.
Value: The type of the Ith element of T. Equivalent to result_of::value_at<I,T>::type.