ChaiScript VS V8

If you want to use C++ for scripting, take a look at Jason Turner's ChaiScript

3) Similiar to 2, but use more common scripting languages: chai, cs-script, sol2 (c++ framework to embed lua)

A few years back I actually went and made a ChaiScript based video game engine (https://16bpp.net/blog/post/masala-a-chaiscript-game-engine/). The end goal for it was to be able to make a Pacman like clone, but have all of the game logic implemented in ChaiScript. I actually found out as I added more realtime elements (implemented in ChaiScript) that it started to take much longer to process the game logic; the "game loop FPS" was under 60, which is not good. I actually proposition that ChaiScript move to a bytecode VM (https://github.com/ChaiScript/ChaiScript/issues/266), but I'm guessing that no movement was made on that front.

Maybe ChaiScript? It is not exactly what you are looking for, but very similar, in my opinion.

Thank god!

Presumably this new API will fix the fact that JS does in fact know about some time zones, but not most.

Shield your eyes from this monstrosity that will successfully parse some dates using `new Date()` in some select special time zones, but assume UTC in the other cases:

https://github.com/v8/v8/blob/781c20568240a1e59edcf0cb5d713a...

And that happened in 2021.

https://chromium.googlesource.com/v8/v8.git/+/HEAD/include/c...

Due to the nature of web engine workloads migrating objects to being GC'd isn't performance negative (as most people would expect). With care it can often end up performance positive.

There are a few tricks that Oilpan can apply. Concurrent tracing helps a lot (e.g. instead of incrementing/decrementing refs, you can trace on a different thread), in addition when destructing objects, the destructors typically become trivial meaning the object can just be dropped from memory. Both these free up main thread time. (The tradeoff with concurrent tracing is that you need atomic barriers when assigning pointers which needs care).

This is on top of the safey improvements you gain from being GC'd vs. smart pointers, etc.

One major tradeoff that UAF bugs become more difficult to fix, as you are just accessing objects which "should" be dead.

> If that standard library would be written in JS, a new browser (or rather a new JS engine being a part of the browser) could just use some existing implementation

That sounds great, but I'm doubtful of the simplicity behind this approach.

If my understanding is correct, v8 has transitioned to C++[0] and Torque[1] code to implement the standard library, as opposed to running hard-coded JavaScript on setting up a new context.

I suspect this decision was made as a performance optimization, as there would obviously be a non-zero cost to parsing arbitrary JavaScript. Therefore, I doubt a JavaScript-based standard library would be an acceptable solution here.

[0]: https://github.com/v8/v8/tree/main/src/runtime

C++ lets you write anything you can imagine, and the language features and standard library often facilitate that. The committee espouses the view that they want to provide many "zero [runtime] cost," abstractions. Anybody can contribute to the language, although the committee process is often slow and can be political, each release the surface area and capability of the language gets larger.

I believe Hazard Pointers are slated for C++26, and these will add a form "free later, but not quite garbage collection" to the language. There was a talk this year about using hazard pointers to implement a much faster std::shared_ptr.

It's a language with incredible depth because so many different paradigms have been implemented in it, but also has many pitfalls for new and old users because there are many different ways of solving the same problem.

I feel that in C++, more than any other language, you need to know the actual implementation under the hood to use it effectively. This means knowing not just what the language specifies, but can occaissionally require knowing what GCC or Clang generate on your particular hardware.

Many garbage collected languages are written in or have parts of their implementations in C++. See JS (https://github.com/v8/v8)and Java GC (https://github.com/openjdk/jdk/tree/36de19d4622e38b6c00644b0...)

I am not an expert on Java (or C++), so if someone knows better or can add more please correct me.

Remember that we earlier established that every source gets parsed into an AST at some point before it gets compiled or interpreted. For example, platforms like Nodejs and chromium-based browsers use Gooogle's V8 engine behind the scenes to run JavaScript and of course, some AST parsing is always involved before the interpreter kicks in. I looked V8's source and I discovered it uses its own internal parser to achieve this.

In the source code of the Node.js opensource project, lib folder contains JavaScript code, mostly wrappers over C++ and function definitions. On the contrary, src folder contains C++ implementations of the functions, which pulls dependencies from the V8 project, the libuv project, the zlib project, the llhttp project, and many more - which are all placed at the deps folder.

Here is the implementation of of Array. prototype.map in V8. It's written in a language called Torque which appears to be a special language just for the v8 engine.