palotasb · HackerTrans

hace 10 mesesdiscuss

What does "loop on itself" mean in this context? The article repeats it 5 times but I can't find a thesaurus definition, and it's unclear to me if the author means it as a synonym repeat or *self-amplify or something different.

palotasb

hace 11 mesesdiscuss

The author is perhaps presenting a good argument for languages/runtimes like JavaScript/Node where dependencies may be isolated and conflicting dependencies may coexist in the dependency tree (e.g., "app -> { libpupa 1.2.3 -> liblupa 0.7.8 }, { libxyz 2.0 -> liblupa 2.4.5 }" would be fine), but the proposed dependency resolution algorithm...

> Our dependency resolution algorithm thus is like this:

> 1. Get the top-level dependency versions

> 2. Look up versions of libraries they depend on

> 3. Look up versions of libraries they depend on

...would fail in languages like Python where dependencies are shared, and the steps 2, 3, etc. would result in conflicting versions.

In these languages, there is good reason to define dependencies in a relaxed way (with constraints that exclude known-bad versions; but without pins to any specific known-to-work version and without constraining only to existing known-good versions) at first. This way dependency resolution always involves some sort of constraint solving (with indeterminate results due to the constraints being open-ended), but then for the sake of reproducibility the result of the constraint solving process may be used as a lockfile. In the Python world this is only done in the final application (the final environment running the code, this may be the test suite in for a pure library) and the pins in the lock aren't published for anyone to reuse.

To reiterate, the originally proposed algorithm doesn't work for languages with shared dependencies. Using version constraints and then lockfiles as a two-layer solution is a common and reasonable way of resolving the dependency topic in these languages.

palotasb

hace 12 mesesdiscuss

^ is the XOR operator, 0 XOR 5 is 5. (Exponentiation is *)

https://docs.python.org/3/library/operator.html#mapping-oper...

palotasb

el año pasadodiscuss

Not compared to the previous state where he worked for an unrelated company and only had his free time to contribute to Headscale.

palotasb

el año pasadodiscuss

> Sourcehut

Is it there yet?

> Notice: sr.ht is currently in alpha, and the quality of the service may reflect that. As such, payment is currently optional for most features, and only encouraged for users who want to support the ongoing development of the site. For a summary of the guarantees and limitations that the alpha entails, see this reference.

– https://sourcehut.org/pricing

palotasb

hace 2 añosdiscuss

The spiral rule works only if there is no pointer to pointer or array of array in the type. In other words it is an incorrect rule. But take this for example:

        +----------------------------+
        | +-----------------------+  |
        | | +------------------+  |  |
        | | | +-------------+  |  |  |
        | | | | +--------+  |  |  |  |
        | | | | |  +--+  |  |  |  |  |
        | | | | |  ^  |  |  |  |  |  |
    int * * ¦ ¦ ¦ VAR[1][2][3] |  |  |
     ^  | | | | |     |  |  |  |  |  |
     |  | | | | +-----+  |  |  |  |  |
     |  | | | +----------+  |  |  |  |
     |  | | +---------------+  |  |  |
     |  | ---------------------+  |  |
     |  +-------------------------+  |
     +-------------------------------+

The type of VAR is a [1-element] array of [2-element] array of [3-element] array of pointer to pointer to ints. I drew a spiral that passes through each specifier in the correct order. To make the spiral correct it has to skip the pointer specifiers in the first three loops. This is marked by ¦.

The Right-Left Rule is quoted less frequently on HN but it's a correct algorithm for deciphering C types: http://cseweb.ucsd.edu/~ricko/rt_lt.rule.html

The spiral rule can be modified to process all array specifiers before all pointer specifiers, but then you'd have to specify that the order to do so is right and then left. At that point it's just the Right-Left Rule.

palotasb

hace 2 añosdiscuss

But https://en.wikipedia.org/wiki/Galileo_(satellite_navigation) panned out and that's a closer analogue.

palotasb

hace 2 añosdiscuss

https://www.theorieexamen.nl/theory-exam/what-is-a-entrance-...

An entrance or exit construction is a place on a road where you aren't just turning onto the road but exiting the road entirely. The most common example from any country would be a private driveway. Pedestrians, cyclists and cars going along the sidewalk, bike path or road have priority against anyone turning into the driveway or turning onto the road from the driveway.

The Netherlands generalizes this concept to some low-priority side streets. If there is a continuous sidewalk (i.e., the cars go up a bump to the level of the sidewalk as opposed to the pedestrians stepping down from the sidewalk to the level of the street). This is not the case in this specific intersection.

palotasb

hace 2 añosdiscuss

Correct, only one.

This specific turn is onto a street that the article describes as "traffic volume here is low, since only residents will use this street." They probably expect the 1-car buffer to be enough for this intersection. You can see in the video that the 1-car buffer is empty most of the time.

For intersections where they expect more turning traffic (where the one car buffer wouldn't be enough), they add turning lanes that can accomodate more than one car. You can see an example of this a few hundred meters northeast when Graafseweg intersects the Van Grobbendocklaan: https://maps.app.goo.gl/ZmURqawr3oeBX5Sq9

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