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For example, it would be interesting to incorporate Ghost Font into CAPTCHA systems, as most systems are easily solved by AI today.

It seems to me like it should be easy enough to take Ghost Font, apply normal video compression techniques, and analyze the compressed signal to recover the visual outline of the letters, which you would then analyze with OCR (or an AI I guess ...). In other words, a novel CAPTCHA technique but not necessarily "fundamentally more difficult" than existing CAPTCHA techniques, once the cat-and-mouse game gets going.

There's a note at the end:

As always, this blog post is written by me, without any AI, so all errors are my own.

However, the illustrations in the post are clearly made by generative AI, are they not?

Of course, if you're implementing POSIX vi, there are quite a few features that have aged poorly, like roff/troff macros and line-editing

What do you mean by "roff/troff macros"?

EDIT: Ah, you're probably talking about the "section-wise" movements, defined in POSIX with language like "A line whose first character is a <period> and whose second and third characters match a two-character pair in the 'sections' edit option (see ex)" - that's the first time I've stumbled upon the 'sections' and 'paragraphs' options in the Vim manual ... Very quaint!

Given a commit that both refactors (A) and adds a feature (B), you can go into the codebase and remove the new feature by hand (B^-1), commit the feature removal, and immediately revert the feature removal. This leads to three commits: (A B), B^-1, and B. Squash the first two commits to obtain a commit that only refactors, and another commit that only adds the new feature. I've written more about this technique ("the Hammer") here: https://github.com/Mortal/gittalk

You can rewrite it using let-or-else to get rid of the unwrap, which some would find to be more idiomatic.

    let value = Some(param.as_ref()) else {
      // Handle, and continue, return an error etc
    }
    // Use `value` as normal.

On a small team I usually already know who wrote the code I'm reading, but it's nice to see if a block of code is all from the same point in time, or if some of the lines are the result of later bugfixing. It's also useful to find the associated pull request for a block of code, to see what issues were considered in code review, to know whether something that seems odd was discussed or glossed over when the code was merged in the first place.

Ooh, core.hooksPath is quite nifty. I usually use something like

         ln -sf ../../scripts/git-pre-commit-hook .git/hooks/pre-commit
which simply adds a pre-commit symlink to a script in the repo's scripts/ dir. But hooksPath seems better.

I don't understand what a dedicated "completely open source offering" provides or what your "five nines feature flag system" provides. If you're running on a simple system architecture, then you can sync some text files around, and if you have a more scalable distributed architecture, then you're probably already handling some kind of slowly-changing, centrally-managed system state at runtime (e.g. authentication/authorization, or in-app news updates, ...) where you can easily add another slowly-changing, centrally-managed bit of data to be synchronised. How do you measure the nines on a feature flag system, if you're not just listing the nines on your system as a whole?

It seems to me that macOS has env -S as well, but the shebang parsing is different. The result is that shebang lines using env -S are portable if they don't contain any quotes or other characters. The reason is that, running env -S 'echo a b c' has the same behavior as running env -S 'echo' 'a' 'b' 'c' - so simple command lines like the one with uv are still portable, regardless of whether the OS splits on space (macOS) or not (Linux).

Oh wow, today I learned about env -S - when I saw the shebang line in the article, I immediately thought "that doesn't work on Linux, shebang lines can only pass a single argument". Basically, running foo.py starting with

    #!/usr/bin/env -S uv run --script
causes the OS run really run env with only two arguments, namely the shebang line as one argument and the script's filename as the second argument, i.e.:
    /usr/bin/env '-S uv run --script' foo.py
However, the -S flag of env causes env to split everything back into separate arguments! Very cool, very useful.

No love for the <plaintext> tag? "The <plaintext> HTML element renders everything following the start tag as raw text, ignoring any following HTML. There is no closing tag, since everything after it is considered raw text." - it's my favorite obscure deprecated HTML tag.

Oh Shit, Git? 2 years ago

Actually, "git reset --soft" moves the current branch to another commit, without moving the index (aka staging area) along with it, whereas "git reset" (aka "git reset --mixed") moves the current branch AND the index to another commit. I really couldn't wrap my head around it before I had gone through "Reset demystified" [1] a couple times - it's not a quick read but I can strongly recommend it.

[1] https://git-scm.com/book/en/v2/Git-Tools-Reset-Demystified

Oh Shit, Git? 2 years ago

For move-branch: Use `git branch -f master HEAD~` if you're currently on another branch, or `git reset --soft HEAD~` if you're currently on master.

You could use handwritten asmjs in that case. I did it at work to improve performance on some pixel-wise software rendering we were doing. (We have since then switched to WebGL, but asmjs was a nice stepping stone.) If I recall correctly, it basically boils down to using small fixed size arrays and appending "|0" after each uint32 operation and "+" in front of each float32 operation - so it's something you can do by hand. Of course, one of my colleagues then made a tweak which gave a surprisingly huge slowdown - you should probably declare loudly (with comments etc.) that a certain code block is intended to be asmjs if you do this in a large codebase.

To run a macro on the start of each line matching your search, you can use:

    :g//norm @q
Here, g// repeats the most recent search, and norm @q runs the q macro on each matched line. This is not quite the same as starting the macro with a search, since the cursor is at the start of the line and not at the start of the match, but it's often good enough.

You can also restrict it to just the matches inside a range of lines: First select the lines in visual mode, then type :g//norm @q, which will cause Vim to insert a range before g, as in: :'<,'>g//norm @q, which means "between line '< and '>, find lines containing a match of the most recent search, and run @q on each such line".

Heads up - you should use "qD instead of "qdd to avoid an extra newline at the end of the register contents. (In fact the current Vim 9.1.954 behavior seems a bit odd in that it moves the cursor down, but not to the start of the line, as if j is pressed... Seems like a bug to me.)

There's also the no-macro solution where you just use ":%norm [series of keystrokes]" to run the given keystrokes on each line, but that comes with the added difficulty of not giving any visual feedback of what the keystrokes will do before you submit the entire line.

One thing to keep in mind is that ":%norm" will place the cursor at the start of each line, before any indentation, whereas the trick of ending the macro with "+" will place the cursor at the start of each line after the indentation. But this can be worked around with ":%norm ^@q", using ^ to skip indentation before running macro q on each line.

Actually, from an algorithmic standpoint it's the opposite: the minimum cover problem (where overlap is allowed) is NP-hard whereas the minimum partition problem (where overlap is NOT allowed) has polynomial-time algorithms. "An Algorithm for Covering Polygons with Rectangles" by Franzblau and Kleitman 1984: https://core.ac.uk/download/pdf/82333912.pdf

However, that's of course just an academic tangent - the theoretical results don't necessarily imply that one problem is easier than the other when you're just getting something to work for an afternoon project.

Noise 2 years ago

The default chords from left to right sound pretty standard in my ears: vii⁰, I, ii, iii, IV, V, vi - but maybe it's locrian if you take the leftmost chord to be the tonic, and a plain major if you take the second from the left to be the tonic?

Solving the duck-rabbit puzzle in Animal Well gave me such chills. In the beginning of the game the player comes across a room with a duck that quacks at you when you walk by. In a distant corner of the world there's a picture of a duck-rabbit with a passcode. When you enter the passcode in front of the duck, it transforms into a rabbit and warps away through a portal that appears for a brief moment while a spooky sound effect plays.