I really recognize the value of new implementations and the fact that each of them is filling a hole that old implementations do not cover (like new platform support, more embeddings, etc.).
But I have a controversial question: why is it better to start a system from scratch than contributing and helping to other less known, long running systems (Yap, XSB, ECLiPSe, Ciao, gprolog, B-Prolog, etc.)?
In the old times, a system became popular because you read a research paper which described carefully the implementation decisions and did good performance evaluations. Papers were reviewed and trusted, you could get objective information about why the implementation was good or not. This helped advance the state of the art.
Nowadays, this is completely broken and it is strangely feeling like a "popularity" contest and a social game. For example, some users were surprised about the performance of WASM-compiled Ciao Playground:
https://ciao-lang.org/playground/
that despite being x2 slower than native, is faster than other popular Prolog implementations. We needed to tweet about it and use the forum of another popular Prolog system to have any visibility. Despite that, this fact will soon be ignored and buried.
When looking at the VM of each of the systems, we know why this happens, but the expertise of the people who wrote earlier Prolog systems, many of them run perfectly fine and blazingly fast in modern machines, is being lost.
Of course, we learned a long time ago that the selection of benchmarks is really complex. You can pick whatever is needed to make your system shine. Ciao Prolog is extremely fast for some benchmarks but it can also be much slower in others.
My claim is that despite it is cool to have new and nice Prolog implementations, this is adding a lot of noise and we are repeating mistakes from the past and going in the wrong direction:
- There is no incentive for proper benchmarking (e.g., should I implement mmap-based file mapping? when does it help? is it a good idea?)
- The literature is being ignored (e.g., who reads and compares with Paul Tarau or Bart Demoen implementation papers?)
- VM and libraries should be independent (it should be possible to implement a new VM while not requiring to reimplementing the whole set of libraries)
- Systems copy/reimplement features without proper recognition of the original system (e.g., once a technique is adopted by the popular system, the original is forgotten, who knows that JITI was originally developed by Vitor Santos Costa in YAP?).
- The community is extremely fragmented.
I wonder if it would be possible to create a more healthy Prolog forum which prioritizes ideas, authors, and results. Going through twitter, discourse, github discussions, github issues, of each of our individual Prolog system is NOT a solution. Each of us looking at decades of research papers and reproducing them in each of our systems is also not a good idea (indeed the unique advantage of old systems is that it takes decades to incorporate some of these ideas). Moreover, there are still many unsolved problems in modern Prolog systems that can only be addressed as programming language research.