> So the big win with functional programming is easier testibility and fewer hazards when trying to multi-thread your code.
To give you my experience: during my phd, I developed https://ossia.io in C++. For the manuscript redaction, I rewrote all the core algorithms in pure functional OCaml. When I did some tests, performance was slower than -O0 C++ (so it's not even a given that multithreaded OCaml would outperform single-thread C++), the tests weren't meaningfully simpler to write, and it would be pretty much impossible to have an average comp. sci. student contribute to the code.
My experience multi-threading C++ code is, "slap cpp-taskflow, TBB, RaftLib" or any kind of threaded task system and enjoy arbitrary scaling. Hardly the pain it is made to be unless you have a need to go down to std::thread level, but even then using something like https://github.com/cameron314/concurrentqueue to communicate between threads makes things extremely painless.
To give you my experience: during my phd, I developed https://ossia.io in C++. For the manuscript redaction, I rewrote all the core algorithms in pure functional OCaml. When I did some tests, performance was slower than -O0 C++ (so it's not even a given that multithreaded OCaml would outperform single-thread C++), the tests weren't meaningfully simpler to write, and it would be pretty much impossible to have an average comp. sci. student contribute to the code.
My experience multi-threading C++ code is, "slap cpp-taskflow, TBB, RaftLib" or any kind of threaded task system and enjoy arbitrary scaling. Hardly the pain it is made to be unless you have a need to go down to std::thread level, but even then using something like https://github.com/cameron314/concurrentqueue to communicate between threads makes things extremely painless.