I have a fusion map in a class which I want to initialize with a variadic constructor template<typename... Args> ctor(Args... args) { ..... } I imagine I would create a fusion vector using make_vector and then iterate over the elements of the map and somehow set the value of each map pair to it's corresponding element in the vector. I think that if I could find the index position of a single element in the map, that I could then use for_each to iterate over the pairs, and use the item's index to retrieve the corresponding value from the vector. Can anyone help me with this? Perhaps there is an alternate better way to do this? TIA Steve