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Small programming language with everything passed by value? You reinvented C?
Not everything in C is pass-by-value. Sure, you can argue that a pointer itself is passed by value, but the data it points to is definitely not.
The threading story here is what grabbed my attention. Pass-by-value with copy-on-write means you get data-race immunity without any locks or channels. You just pass data to a thread and mutations stay local. That's a genuinely useful property. I've worked on systems where we spent more time reasoning about shared state than writing actual logic. The typical answer is "just make everything immutable" but then you los…
Hmm this is a bit like peeling a banana only to throw the banana and eat the peel. Pass by value reduces the true benefit of copy-on-write. Use immutable pass by reference. Make a copy only if mutability is requested in the thread. This makes concurrent reads lock-free but also cuts down on memory allocations.
The threading story here is what grabbed my attention. Pass-by-value with copy-on-write means you get data-race immunity without any locks or channels. You just pass data to a thread and mutations stay local. That's a genuinely useful property. I've worked on systems where we spent more time reasoning about shared state than writing actual logic. The typical answer is "just make everything immutable" but then you los…
Nothing "real", just the synthetic benchmarks in the ./benchmarks dir.
Unnecessary copies are definitely a risk, and there's certain code patterns that are much harder for my interpreter to detect and remove. E.g. the nbodies has lots of modifications to dicts stored in arrays, and is also the only benchmark that loses to Python.
The other big performance limitation with my implementation is just the cost of atomic reference counting, and that's the main tradeoff versus deep cloning to pass between threads. There would definitely be room to improve this with better reference counting optimizations though.
The threading story here is what grabbed my attention. Pass-by-value with copy-on-write means you get data-race immunity without any locks or channels. You just pass data to a thread and mutations stay local. That's a genuinely useful property. I've worked on systems where we spent more time reasoning about shared state than writing actual logic. The typical answer is "just make everything immutable" but then you los…
The threading story here is what grabbed my attention. Pass-by-value with copy-on-write means you get data-race immunity without any locks or channels. You just pass data to a thread and mutations stay local. That's a genuinely useful property. I've worked on systems where we spent more time reasoning about shared state than writing actual logic. The typical answer is "just make everything immutable" but then you los…
Pass-by-value is already a copy.
The threading story here is what grabbed my attention. Pass-by-value with copy-on-write means you get data-race immunity without any locks or channels. You just pass data to a thread and mutations stay local. That's a genuinely useful property. I've worked on systems where we spent more time reasoning about shared state than writing actual logic. The typical answer is "just make everything immutable" but then you los…
The threading story here is what grabbed my attention. Pass-by-value with copy-on-write means you get data-race immunity without any locks or channels. You just pass data to a thread and mutations stay local. That's a genuinely useful property. I've worked on systems where we spent more time reasoning about shared state than writing actual logic. The typical answer is "just make everything immutable" but then you los…
Earlier quoted context omitted.
Pass-by-value is already a copy.
It's only semantically a pass-by-value, in reality a reference is passed and the data is only copied if needed (i.e. value is mutated while shared).
(Ah, no, your example elsewhere in the thread suggests that the referred-to structures get implicitly copied all over the place.)