rvirding · HackerTrans

The reason for calling it Luerl was that it was/is an implementation of Lua on Erlang. It is Dave who has been working with a more serious Elixir interface. The original one, which still exists, had a very simple Elixir interface module which just flipped the argument ordering to calls to be more Elixiry in feel.

rvirding

3 tahun yang laludiscuss

I would be very interested about the architectural possibilities of the BEAM you mentioned. Also the speed of the BEAM is not as bad as is often mentioned, definitely not when you start looking at problems/tests with lots of inherent concurrency. Also the sequential speed has markedly improved with the new ASMJIT.

Also problems with GC basically don't exist when running Erlang/LFE code, at least you have to put a lot of effort into getting problems with GC. A lot! And, of course, the BEAM does automatic load balancing over multiple cores which is another problem gone away. We never have to think about the class of problems like "I have my system set up to run on 2 cores, how should I modify it to run on 4?".

rvirding

3 tahun yang laludiscuss

I think the thing to remember that it all started as an interpreter written in Prolog in which we could develop our ideas on what the real problem was and the right semantics of a system for solving them. As we went along our "language" evolved as well and became less and less Prolog and more functional as we removed much Prolog semantics, added functional "stuff" and developed the final syntax.

We had along the way also looked at concurrent logic languages. So by the time we had a language and design rules how to use it most of Prolog had disappeared, though some of its syntax still remained. This language was, of course, Erlang.

While Prolog was a nice base on which to develop our ideas it was never the language we would have used in real life.

rvirding

3 tahun yang laludiscuss

OTP came much later than the design of the language.

The language was designed around our I ideas of what the problem really was and the best way of solving it. The massive and extremely lightweight concurrency were a critical part of attacking the problem which was/is extremely concurrent. There are an enormous number of things going on in a switch which have to be handled concurrently, sometime over 10k calls plus running the switch. So the concurrency was fundamental. The error handling primitives were of course also a a critical part of the solution as fault tolerance was a critical part of the problem.

A lot of effort went in to working out what the concurrency and error handling should look like to be right for how to attack the issues and solve the problems. Fortunately we worked with a user group looking at designing a new architecture who tested using our ideas and came with extremely important feedback on the ideas, what was good or bad or just not necessary. They then became the first group to build a product using Erlang. It didn't use OTP as it didn't exist then.

OTP came later and is “just” a formalised, generic wrapper around these ideas. We had client-servers, state machines and the equivalent to supervisors in products before OTP was developed. Behaviours came with OTP. And in the beginning there were many different versions of OTP alive at the same time.

Behaviours could not have been developed as they are without lightweight processes and communication. OTP is of course fundamnetal to the distribution and use of the language as it does encapsulate most of of our original ideas in how Erlang should/could be used to build systems.

comments