j-pb

35 ms·

421.
by j-pb 4y ago
Rusts entire trait model is a pretty big deal. The main issue is with memory semantics however, stuff like tagged 64bit pointers are UB land pretty much immediately. MiniRust solves this by providing an explicit memory interface trait.
422.
by j-pb 4y ago
> UB doesn't exist at an assembly level cough https://riscv.org/wp-content/uploads/2018/05/10.45-clifford-... There are plenty of undefined things in ISAs, writing to some internal ARM registri
423.
by j-pb 4y ago
Assembly in the macro-assembler sense. Doesn't matter that it's obscure and not a direct mapping to any specific ISA, there is still relatively straightforward mapping between syntactic constructs and something von neumann-ish. Ru
424.
by j-pb 4y ago
C++ is arguably the most complex programming language ever. There is not much to be gained by comparing against the supremum. Take a look at the languages that rust was influenced by ( https://en.wikipedia.org/wiki/Rust_
425.
by j-pb 4y ago
It's still a good example where the specification is in flux and a lot of documentation virtually non-existent (e.g. std), but that is still very usable, simply due to the fact that it isn't a very complex language in terms of sem
426.
by j-pb 4y ago
The major difference between Rust and [Zig, C] is that the latter are essentially "cocky macro assemblers". They derive their semantics from the semantics of the underlying assembly. Take https://github.com/ziglang
427.
by j-pb 4y ago
Awesome! Rusts ad-hoc "the compiler is the specification" has always been a huge turnoff for me, and a huge hurdle when learning the language. The language is just too complex and the compiler is too large and smart/magical t
428.
by j-pb 4y ago
Theres an issue with this "one review fits all" approach. Scientific communities are often splintered into sub-communities with different views and allegiances. The scientific community is not a set, it's a graph with differe
429.
by j-pb 4y ago
I really wonder what the memory overhead of the prolly tree is. Using hashes as links isn't cheap especially with sha-512 wide hashes (I think they use 20bytes in reality?). I'd estimate their fanout at between 50-200, which isn&#
430.
by j-pb 4y ago
Perfect for this non-spec.
431.
by j-pb 4y ago
Those trains yes, because it's the grid that powers them (through constantly connected overhead lines). There is not really the need to feed that energy back to the grid though, as there are plenty of other trains that are happy to gob
432.
by j-pb 4y ago
> Crop farming is ruining the soil way faster than grazing livestock. But what is all that crop used for? Livestock. > Livestock grazing the land is a lot closer to how the land was before we came along than a rainforest. Freudian sli
433.
by j-pb 4y ago
68% is Burnt for pastures for Cattle Farming. 28% is Burnt for Agriculture, of which 60% is for soybeans, of which 77% are shipped overseas for (you guessed it) livestock feed. Palm Oil plants are only 12% of those 28%. That means at least
434.
by j-pb 4y ago
No need to put sustainable in quotes. Livestock farming is ruining the soil, the water, a major producer of CO2, the main producer of Methane, and the root cause for the burning of the rainforest.
435.
by j-pb 4y ago
This is about land used for grazing. Even if there is no meat or diary, you don't have a famine. People starve if you don't have grains and vegetables. Considering how much land is being used for livestock feed, switching to a pl
436.
by j-pb 4y ago
That blogpost is a godsend, it provides a great explanation and intuition, and resolved a few questions that I was left with after reading a lot of WCO join papers. Good nitpick, I think you can construct larger rings where the difference b
437.
by j-pb 4y ago
The intuition is that if your join is a triangle you might be forced to join every relation only to discover that the result is empty on the last join, which requires m^n intermediary results, where m is the size of the relations and n is t
438.
by j-pb 4y ago
DPLL, see https://arxiv.org/pdf/1912.12747.pdf
439.
by j-pb 4y ago
C++ is probably the slowest programming language in terms of development speed there is, but even if it takes you 3 months to build something like that from scratch it'll still be an order of magnitude less time than building a clone o
440.
by j-pb 4y ago
While the technical terms may be unfamiliar, it's all pretty straightforward, and requires between 1-4kloc depending on how fast and fancy you want things to be. (This includes everything from the basic copy on write data-structures to
441.
by j-pb 4y ago
If you just pick a worst case optimal join algorithm with a limited table cardinality, i.e. triples like in the case of OP, so that you can materialise every possible index, you can perform a dynamic _instance optimal_ search (i.e. you can
442.
by j-pb 4y ago
Really interesting point. I always figured I'd go with an ECS system like specs for the high perf case, but you're absolutely right, columnar storage is gonna be orders of magnitude faster. (Fun fact, the hibitset of specs looks _
443.
by j-pb 4y ago
I'm a huge fan of your work. Is there a reason why you didn't pursue the triple model of EVE and went with tables instead? It feels like the former would be such a great fit for the knowledge representation side of robotics.
444.
by j-pb 4y ago
If only ROS were that. ROS wasn't a particularly good Middleware, and ROS2 isn't a middleware at all (DDS is a middleware, ROS is a framework using DDS). The issue with ROS isn't the general idea of communicating nodes over a
445.
by j-pb 4y ago
The issue with ROS are mostly cultural, and heavily ingrained into the community. ROS2 isn't going to fix that and has been shown to repeat the same mistakes of ROS. The atrocious build system has stayed the same. People continue to ad
446.
by j-pb 4y ago
While hardware accelerators in robotics are very cool, and needed. The fact that the entire workflow is ROS2 centric is a bummer. FPGA and Accelerator Programming is already a huge PITA, and despite it's success ROS is really one of th
447.
by j-pb 4y ago
M3 if water is not the usefull metric here, but energy. It takes energy to produce clean drinking wanter, and sinularly a lot of energy to head said water up. A cycling system significantly reduces the energy footprint of both.
448.
by j-pb 4y ago
This project seems to fit your need perfectly. It's open hardware, and designed for showers, but should be easily retrofittable for your specific faucet case. https://showerloop.org/
449.
by j-pb 4y ago
I think your issue has nothing to do with rust, and is all about WASM being executed on the main event loop thread. Rust can't magically create parallelism (this is not even an concurrency thing which is what async provides) where ther
450.
by j-pb 4y ago
After reading the discussion, I think I'm much more in favour of adding tail calls, than adding exceptions. Actually I wonder if one couldn't adapt the tail-call mechanism slightly to also serve as an exception mechanism. I think

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