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Cake day: June 25th, 2023

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  • Unfortunately both of those are used in common English or computer words. The only letter pairs not used are: bq, bx, cf, cj, dx, fq, fx, fz, hx, jb, jc, jf, jg, jq, jv, jx, jz, kq, kz, mx, px, qc, qd, qg, qh, qj, qk, ql, qm, qn, qp, qq, qr, qt, qv, qx, qy, qz, sx, tx, vb, vc, vf, vj, vm, vq, vw, vx, wq, wx, xj, zx.

    Personally I have mappings based on <CR>, and press it twice to get a real newline.


  • Even logging can sometimes be enough to hide the heisgenbug.

    Logging to a file descriptor can sometimes be avoided by logging to memory (which for crash-safety includes the possibility of an mmap’ed file, since the kernel will just take care of them as long as the whole system doesn’t go down). But logging from every thread to a single section of memory can also be problematic (even without mutexes, atomics can be expensive and certainly have side-effects) - sometimes you need a separate per-thread log, and combine in the log-reader tool.



  • I haven’t managed to break into the JS-adjacent ecosystem, but tooling around Typescript is definitely a major part of the problem:

    • following a basic tutorial somehow ended up spending multiple seconds just to transpile and run “Hello, World!”.
    • there are at least 3 different ways of specifying the files and settings you want to use, and some of them will cause others to be ignored entirely, even though it looks like they should be used.
    • embracing duck typing means many common type errors simply cannot be caught. Also that means dynamic type checks are impossible, even though JS itself supports them (admittedly with oddities, e.g. with string vs String).
    • there are at least 3 incompatible ways to define and use a “module”, and it’s not clear what’s actually useful or intended to be used, or what the outputs are supposed to be for different environments.

    At this point I’m seriously considering writing my own sanelanguage-to-JS transpiler or using some other one (maybe Haxe? but I’m not sure its object model allows full performance tweaking), because I’ve written literally dozens of other languages without this kind of pain.

    WASM has its own problems (we shouldn’t be quick to call asm.js obsolete … also, C’s object model is not what people think it is) but that’s another story.


    At this point, I’d be happy with some basic code reuse. Have a “generalized fibonacci” module taking 3 inputs, and call it 3 ways: from a web browser on the client side, as a web browser request to server (which is running nodejs), or as a nodejs command-line program. Transpiling one of the callers should not force the others to be transpiled, but if multiple of the callers need to be transpiled at once, it should not typecheck the library internals multiple times. I should also be able to choose whether to produce a “dynamic” library (which can be recompiled later without recompiling the dependencies) or a “static” one (only output a single merged file), and whether to minify.

    I’m not sure the TS ecosystem is competent enough to deal with this.


  • I’ve done something similar. In my case it was a startup script that did something like the following:

    • poll github using the search API for PR labels (note that this has sometimes stopped returning correct results, but …).
      • always do this once at startup
      • you might do this based on notifications; I didn’t bother since I didn’t need rapid responsiveness. Note that you should not do this for the specific data from a notification though; it’s only a way to wake up the script.
      • but no matter what, you should do this after N minutes, since notifications can be lost.
    • perform a git fetch for your main development branch (the one you perform the real merges to) and all pull/ refs (git does not do this by default; you’ll have to set them up for your local test repo. Note that you want to refer to the unmerged commits for these)
    • if the set of commits for all tagged PRs has not changed, wait and poll again
    • reset the test repo to the most recent commit from your main development branch
    • iterate over all PRs with the appropriate label:
      • ordering notes:
        • if there are commits that have previously tested successfully, you might do them first. But still test again since the merge order could be different. This of course depends on the level of tests you’re doing.
        • if you have PRs that depend on other PRs, do them in an appropriate order (perhaps the following will suffice, or maybe you’ll have some way of detecting this). As a rule we soft-forbid this though; such PRs should have been merged early.
        • finally, ordering by PR number is probably better than ordering by last commit date
      • attempt the merge (or rebase). If a nop, log that somewhere. If not clean, skip the PR for now (and log that), but only mark this as an error if it was the first PR you’ve merged (since if there’s a conflict it could be a prior PR’s fault).
      • Run pre-build stuff that might need to create further commits, build the product, and run some quick tests. If they fail, rollback the repo to the previous merge and complain.
      • Mark the commit as apparently good. Note that this is specifically applying to commits not PRs or branch names; I admit I’ve been sloppy above.
    • perform a pre-build, build and quick test again (since we may have rolled back and have a dirty build - in fact, we might not have ended up merging anything!)
    • if you have expensive tests, run them only here (and treat this as “unexpected early exit” below). It’s presumed that separate parts of your codebase aren’t too crazily entangled, so if a particular test fails it should be “obvious” which PR is relevant. Keep in mind that I used this system for assumed viable-work-in-progress PRs.
    • kill any existing instance and launch a new instance of the product using the build from the final merged commit and begin accepting real traffic from devs and beta users.
    • users connecting to the instance should see the log
    • if the launched instance exits unexpectedly within M minutes AND we actually ended up merging anything into the known-good branch, then reset to the main development branch (and build etc.) so that people at least have a functioning test server, but complain loudly in the MOTD when they connect to it. The condition here means that if it exits suddenly again the whole script goes up and starts again, which may be necessary if someone intentionally tried to kill the server to force a new merge sequence but it was too soon.
      • alternatively you could try bisecting the set of PR commits or something, but I never bothered. Note that you probably can’t use git bisect for this since you explicitly do not want to try commit from the middle of a PR. It might be simpler to whitelist or blacklist one commit at a time, but if you’re failing here remember that all tests are unreliable.