aarchi

7 ms·

1.
by aarchi 3y ago
PostgreSQL is Turing-complete, as proven by implementations of a cyclic tag system[0] and Turing machine[1]. The Mandelbrot set[2] and travelling-salesman problem[3] have also been implemented in it. Transact-SQL is also Turing-complete, as
2.
by aarchi 4y ago
I'm currently building a couple of regexp engines: One, that's a formalization[0] in Coq with big-step semantics, which uncommonly has the intersection operator, and includes several equivalence relations and a proof of the pumpin
3.
by aarchi 4y ago
The (preprint) paper links to its repository, where its code eventually will be. I suspect it will be pushed around August 2023, before USENIX Security'23, where it will be published. https://github.com/sslab-gatech&#x2
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by aarchi 4y ago
> Other contamination was also found in or on: three buses, 42 houses, fourteen cars, five pigs, and 50,000 rolls of toilet paper Why such a large figure for toilet paper? Is it somehow more easily contaminated by radiation?
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by aarchi 4y ago
This makes me want to dump all my TI-Basic programs from my calculator and put them into source control.
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by aarchi 4y ago
I just got a terrible idea: combine this with another project, that built Tetris in Conway's Game of Life. That would enable executing an arbitrary program in Tetris, simulated in Game of Life. https://codegolf.stackexchange
7.
by aarchi 4y ago
Zettelkästen certainly aren't new, as the technique was popularized in the 1950s and had been around for much longer.
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by aarchi 4y ago
Try doing it in Whitespace then :) https://github.com/andrewarchi/ws-challenges
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by aarchi 4y ago
I've created a similar repo of puzzles, including Advent of Code, but solved in the Whitespace programming language. Even otherwise easy puzzles are made significantly more difficult in Whitespace, as it is a quite low-level language.
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by aarchi 4y ago
To see if gojq works even with complex jq programs, I tested it on my wsjq[0] Whitespace language interpreter, which uses most of the advanced jq features. It impressively appears to support the full jq language, though I uncovered a bug[1]
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by aarchi 4y ago
According to Guinness, the top is Voyager 2: > The computer system that has been in continual operation for the longest period is the Computer Command System (CCS) onboard NASA's Voyager 2 spacecraft. This pair of interlinked comput
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by aarchi 4y ago
In my fork of the article, I added documentation links and ordered the sections more sensibly: https://github.com/andrewarchi/compiler-notes/blob/main/rust...
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by aarchi 4y ago
> you can use a "folder structure" of tags. You can name tags things like subcomponent/v1.0.2. […] Doing that can confuse git describe Using the --match option, `git describe --match='subcomponent/*'` fixes
14.
by aarchi 4y ago
In fact, jq already has `map`, which would replace the article's pattern of `[.[]|add]` with `map(add)`. It is defined as such: def map(f): [.[] | f]; Many built-in functions in jq are implemented in jq, in terms of a small se
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by aarchi 5y ago
> Parcel CSS is based on the cssparser[0] Rust crate, a browser-grade CSS tokenizer created by Mozilla and used in Firefox. This provides a solid foundation, including tokenization and basic parsing. However, it does not interpret any CS
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by aarchi 5y ago
Was this a port of the Flash app or reverse engineering it? The description on GitHub mentions that the Flash version was made by your friend, so I presume you have the original source available. I've wanted to port an old Flash game f
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by aarchi 5y ago
I'm solving Advent of Code in Whitespace, a quintessential esolang. https://github.com/andrewarchi/ws-challenges
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by aarchi 5y ago
I implemented a Whitespace interpreter in jq! https://github.com/andrewarchi/wsjq
19.
by aarchi 5y ago
What timezone is that? I don’t see it in the tz database. My favorite may be Lord Howe Island in Australia (Australia/Lord_Howe), which uses +10:30 in the winter and +11:00 in the summer.
20.
by aarchi 5y ago
> instead of refreshing like a lunatic for new information all the time during your day. You simply search for a solution only when you are experiencing a problem. > You treat social media like any other website online. You visit it o
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by aarchi 5y ago
Adjacency matrices would make ownership clear and solve the single-writer/multiple-reader issue because nodes wouldn't directly reference each other, but it keeps the exact same relationship between nodes, so any memory leaks are
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by aarchi 5y ago
I’m in the early stages of working a compiler in Rust and haven’t gotten to the IR infrastructure yet. With Rust’s borrow checker, how can I make the IR graph safe, with its control flow preds and succs and data flow inputs that make it so
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by aarchi 5y ago
I always find it interesting how frequently Dutch is intelligible, knowing German and some basic sound shifts: „Ihr Gulden ist hier einen Thaler wert“
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by aarchi 5y ago
Nuitka looks like a traditional ahead-of-time compiler using SSA form[0] and is written in Python. I’d be interested in seeing performance comparisons with PyPy, which uses the second Futamura protection and is written in a dialect of Pytho
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by aarchi 5y ago
> This was all done within Europe where we have the highest concentration of tor nodes. So Tor nodes take locality into account? Although, that would improve speeds, it seems like an information leak.
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by aarchi 5y ago
Internet Archive collections are available as web seed torrents and download much faster than over HTTP because multiple servers are used concurrently.
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by aarchi 5y ago
It can be just `jq {q} file.json`. No need for `cat`.
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by aarchi 5y ago
Frequency illusion > The frequency illusion is that once something has been noticed then every instance of that thing is noticed, leading to the belief it has a high frequency of occurrence https://en.wikipedia.org/wiki&#
29.
by aarchi 5y ago
jq is unsurprisingly Turing complete, so I wrote a Whitespace interpreter[0] in jq. It is able to handle real-time I/O by requesting lines on-demand from stdin, which is the main input source, with `input` and outputting strings in a s
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by aarchi 5y ago
Are there any significant languages that do parsing with derivatives?

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