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Comment by loup-vaillant | Hacker News Reader

Some prejudices are rational. To paraphrase, it would take an enormous amount of prior trust and respect before I even humour someone trying me to convince me the sky is green with a straight face.

Some issues are settled enough that there is no need to discus them any further. It is okay to automatically mark people on the wrong side of such issues… let’s say ill-informed.

Static typing, I believe, is close to being one of those issues.

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I think this is OK as long as you keep your mind open to situations that you have not considered.

Imagine someone is working in a relatively niche new programming language ecosystem which is dynamically typed, allowing the language to have some richness that modern type systems don't support. I don't have an example because I don't know of any such language in 2023... BUT back in the 70s and 80s this would have been Lisp. Lisp couldn't have been strictly typed back then because, AFAICT, type systems hadn't advanced enough to express the sort of metaprogramming that made Lisp unique and awesome. This was at a time when most popular languages were strictly typed.

I would hope that you would keep your mind open to whatever that maps to in the 2020s.

Now, if someone says "I like JS over TS because types are annoying and slow me down", then yeah, I don't have much patience for that either.

You make points that seem great to me although I know almost nothing about Lisp or 20th century programming.

The thing is, I've yet to encounter a single instance of such an argument today. Every single time it ends up being "I like JS over TS because types are annoying and slow me down". It hadn't even occurred to me that laziness and sloppiness weren't the the only reasons to write in dynamically typed language.

I suppose what I'm saying is I'm quite interested in seeing what kind of evolution some dynamically typed language could offer in the future. Although with no signs of its coming, I'm going to stick to TS because it's objectively better for anything but very small projects.

TS is an interesting example to pick when trying to argue that types are better. You have all the same downsides people pick on when arguing against strong, static typing, but since the type system isn't sound you still can't rely on the input to a function being the type you expect (and the problem is worse anywhere you inevitably interact at least a little with the JS world outside your TS bubble).

At best it's a form of documentation that enables some simple linting rules and a bit of jump-to-definition magic. Like, that's a benefit (mostly -- I tend to think that type signatures implying more guarantees than they provide is a recipe for inadvertently relying on falsehoods), but it's not as clear-cut of a win as you see in other statics/dynamic tradeoffs.

> The thing is, I've yet to encounter a single instance of such an argument today.

I don't mean to be unnecessarily contentious, but isn't that the point of undiscovered territory?

We haven't encountered it yet, when we do then as awareness grows that pattern, idiom, theorem or concept will be picked up by mainstream statically typed languages.

It's enough to believe that the properties of (for example) JavaScript might lead to an as yet undiscovered pattern that is not possible in current statically typed languages.

Unlikely, but still possible.

Yes sure, it's always possible. My narrow experience leads me to believe, however, that some necessary threshold hasn't been crossed yet. And there's vanishingly little chance that I personally will be participating in such a revolution. Therefore from my perspective, it isn't happening yet and I can only wait to see if it does - meanwhile, I'm on the opposite side.

Python fits that niche now. Half the way tensorflow, et al work is by doing brain surgery on the AST in a way that resembles hey day Lisp's 'even the code is just s-expressions, process it as much as you want to the point of 80/20ing your way to your own compiler'.

Imagine working on a networked system that uses types to make it impossible to express operations that violate data security and integrity constraints, and where such constraints control whether data is allowed to be read or written from or to a given endpoint. Imagine further that the types governing permission to read or write depend on environmental state that can change at any time--for example, as soon as a specific person changes roles, the set of ports they are allowed to read and write changes.

The type system enforces those permissions: writing to an impermissible destination is a type error. The types applicable to an entity are not necessarily knowable at compile time; some of them might change at any time.

I had a job working on such a system. It supported a type system implemented in Haskell with both static and dynamic type disciplines, where values were tagged with base types designed to be checked dynamically in hardware.

Was the programming language dynamically typed? Yes. Was the programming language statically typed? Yes.

It sounds like you have an implicit prejudice against those who do not "keep [their] mind open to situations that [they] have not considered", since the way you phrased your concern is moral in nature. You see it as morally bad not to have an open mind in that way.

As Carl Sagan said: it's good to have an open mind, but not so open your brains fall out.

Yeah, sure, I do in fact think it is virtuous to be aware that we don't always have complete information and that we should be willing to revise our opinions when new information is encountered. Is that controversial?

No, no, not controversial. I intended to make it easier to understand the point by demonstrating for the more literal-minded that using moral language sets up two halves of a dichotomy, one preferred to the other, so that such prejudices needn't be personal but rather merely moral. The difference is of course that which side of a moral dichotomy is a choice that can be reversed (e.g. making an effort to open the mind) while personal matters are immutable in those people.

If your prejudice prevents you from having a conversation with Matz or Jose Valim or Van Rossom or the creators of Julia about software development, you may want to reconsider your prejudice as a hard and fast rule.

You can't honestly believe no one who likes to develop in a dynamically typed language has nothing interesting to say about software development?

If I have pre-existing respect for someone I will hear them about. But the bar for that conversation is high.

I'm not sure what is worse, loving dynamic languages or having all these pre-existing conditions

Doesn't everyone have those? Like, I'm unlikely to really engage with someone about my health unless they're a doctor or otherwise have some area of expertise. Or if it's just a casual, friendly conversation, to kill some time.

Everyone has biases. But you aren't describing a bias, you are describing a refusal to engage with people below you. Speak for yourself, I don't have that.

We’re all humans and life is very complicated with many facets. If we all looked hard enough I’m sure we could find a person you’d refuse to engage in a debate with over their “thing.”

But that wouldn’t be a wise use of time in my opinion. And that’s what they’re ultimately driving at: we all have limited time to expend, so do it in things that matter to you. I believe “matters to you” is a bias.

"Below you" is a bit of an exaggeration, I think. I said that I might think less of someone as a software engineer if they express an opinion that I think is particularly bad. Hardly egregious, in my opinion. I also might not - it frankly depends a lot on the situation.

These people opinions are based on bad information.

Beliefs inform decisions and other beliefs

I disagree with them on a huge number of fundamental things in software. Most of their fundaments are claims with no evidence. Due to that, I simply do not care about what they have to say most of the time.

I can't (or, more accurately, don't) believe that, but I can certainly believe they have nothing interesting to say about the topic of static vs dynamic typing.

I'm very much with you on static typing but you've closed your mind with a slam. Please don't.

An open mind is like a fortress with its gates unbarred and unguarded.

It is both useful and allowed to have a certain level of belief that won’t be crossed without heavy effort. The OP didn’t even say they were closed to the conversation completely, but that a random person with no pre built trust isn’t going to get the time of day from them to rehash the same settled argument.

"Matz or Jose Valim or Van Rossom or the creators of Julia"

from memory Matz -> ruby, Valim-> elixir, Van Rossum -> python, and 'the creators of Julia' -> julia

Not 'random persons' then

Yea, the OP was referencing randos from his perspective and the responder subbed in famous software developers. They weren’t arguing on the same point

Python got type hints bolted on. A type system for Elixir is being worked on. Dynamic typing was a prerequisite for Erlang to enable hot-code-reloading. Julia is can be typed for an extra speedup. Stripe built a type checker for Ruby called Sorbet.

Julia generates fast code without type annotations (except for your data types).

> (except for your data types)

This confused me for a moment, but I think you mean annotating the types of the fields in your `struct`s, right?

An addition to that: any non-constant global variables (if you must have those) should also be type annotated.

idk about the others but much of Guido's development energies the past few years have been spent building Python's gradual static typing system.

To be honest, I think dynamic typing must contain a mind trap. Very smart people fall in.

I'd love a dynamically typed scripting language with the following two properties: no "import" mechanism to split code over multiple files, and no way to execute more than (say) 256 lines of at most 128 bytes each in the file.

Dynamic types are nice for quick & short scripts, and actively detrimental for anything long and complex. Why not enforce that? As soon as it gets so long it doesn't run you know it's time to rewrite in a statically typed language. Instead all existing scripting languages allow unlimited growth in code size, making it easy for programs to grow beyond the point where the language is useful.

> Dynamic types are nice for quick & short scripts

A long list of big products and companies are there to disagree with this. I am not saying that dynamic is better or worse. But saying that dynamic languages are only good for quick short scripts is a wrong generalization that has not one exception but many exceptions.

> To paraphrase, it would take an enormous amount of prior trust and respect before I even humour someone trying me to convince me the sky is green with a straight face.

Don't venture into tornado country; your doubt may be your downfall.

> To paraphrase, it would take an enormous amount of prior trust and respect before I even humour someone trying me to convince me the sky is green with a straight face.

But people regularly say the sky is blue, and it's clear as day that it's not when the earth has turned and your side isn't facing the sun.

The sky is still blue, the lack of light means you cannot tell, but the color is still there.

no... the sky is clear, and it's the refraction of light through the atmosphere that's confusing you.

As someone who would die without an atmosphere the distinction is meaningless.

you're going to die regardless. The sky still isn't blue, which is quite obvious at night, or during sunsets and sunrise.

I don't think that's a statement that most would agree with. What is the sky? Sure the atmosphere can be called blue, but the sky is what's visually above the earth. At night, that's black space. The atmosphere is mostly transparent at night.

The sky isn’t inherently blue. It’s essentially colorless.

Only due to Rayleigh scattering do we perceive it as blue, but that’s not due to the absorption and reflection of different wavelengths we associate with innate color. Note that the color changes depending on the angle of the sun, even to the point that it’s purple and red at a few times during the day.

Perhaps, only because the sky is blue we perceive blue as blue. If the sky were red we would perhaps perceive all red like we do blue.

Our perception of the important colors (sky blue, ocean blue, vegetation green, …) probably evolved along with our physical needs.

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