This was an exciting week. I was finally going to remove load.cpp but well, when does it go according to plan.
As soon as I removed load.cpp I was bombarded with include errors(which was expected). Upon solving some we realised that the load.hpp might require some changes in the way it defines fucntions. At this point Omar suggested to use SFINAE.
SFINAE(substituion failure is not an error) applies during overload resolution of function templates: When substituting the explicitly specified or deduced type for the template parameter fails, the specialization is discarded from the overload set instead of causing a compile error.
This feature is used in template metaprogramming.
Here is a small usecase
template<typename T>
std::enable_if_t<std::is_integral<T>::value> f(T t){
//integral version
}
template<typename T>
std::enable_if_t<std::is_floating_point<T>::value> f(T t){
//floating point version
}You can see here how mlpack utilizes SFINAE.
This was a new concept for me. Omar helped me out with a basic example to get me started on it. After some initial struggle and understanding thanks to Ryan who took out time and took a small 15 minute session on SFINAE and how it is used in mlpack.
I have my concepts a bit clear now, but this task made me realise that there is a lot in C++ which I still need to learn. To follow up on this I’ve decided to dedicate some time daily to study modern C++.
I found this YT Channel very helpful to get a deep dive on the concepts. They also have their github repo links which contains presentaions and other materials used in the conferences.
Next week we are planning to start removing the boost::spirits and connecting the DatasetMapper with the new parser’s implementation. I will also update more on how I handled SFINAE.