This is an experiment I started to see if C++ with coroutines (still experimental) can be used to develop using Erlang style. I.e. a framework where individual coroutines are extremely cheap to construct and asynchronous IO is easy to use. It's also type safe (unlike Erlang) and has the ability to segfault from anywhere (also unlike Erlang?).
It also served the purpose of teaching myself how coroutines work.
There are a couple of examples (in the examples/ directory) that I've written, and if I get more time I might even add more (for example a simple web server). The current ones show things like:
- Spawn a million "processes"
- TCP listener
- Back pressure on sending messages
- Receive messages with timeouts
So many right now:
- Not enough unit tests
- I haven't actually tested it properly (valgrind)
- The API changes on my whims
I have some ideas for making it more multithreaded, but right now it only runs in one thread. This is quick and good enough for everything I've needed thus far. If it's good enough for Node, hopefully its good enough for this.
The dependency right now to build Eslang is Boost with OpenSSL, and to build the tests Google Test.
This used to be an aboslute nightmare, but then I learnt about vcpkg.
- install vcpkg somewhere
- install (I think) boost and google test vcpkg things
- build as per vcpkg instructions
No idea. Never tried it, but hopefully cmake just works? It cannot be worse than building on Windows.
No.
Not yet.
The basic idea though, is that you create an s::Context, and then spawn some "Processes" into it. These are created by you, and have a void run(); method. These processes can then send and receive messages via the context and spawn further subprocesses. This is all kind of similar (in theory) to how Erlang does things, so if you know Erlang - this might look familiar.
It kind of comes from Erlang, but C++ style. So (Er++)lang == Eslang. ish.
I have never actually used Erlang in anything coming close to a real project, so I may have completely misunderstood many things.