Comment by _6pvr | Hacker News Reader

Comment by _6pvr | Hacker News Reader

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> Unfortunately I am too lazy and careless to use Clojure in any serious capacity though. I really need a Haskell or Rust compiler to remind me of all my silly mistakes. I can't be trusted to get to the same level of confidence through unit tests or linting or spec or malli.

I think most developers cannot be trusted to make these mistakes, I wouldn't call it "careless or lazy". Languages exist with tools baked into them to prevent slip ups. Why wouldn't you want to take advantage of that tooling?

Also, as a result of this comment section, this is the second time in the past week that I've seen the suggestion to use 3rd party typechecking/static analysis tooling in a dynamic language, which (to me) brings up the question: Do you really want a dynamic language, or do you just want the ability to be careless intermittently? There is no shame in saying "I just want to get happy-path code working quickly". There is joy in getting happy path working quickly. I just think, as a codebase in a dynamic language grows, codebases seem to build lots of tooling to make that dynamic language less dynamic.

> Do you really want a dynamic language, or do you just want the ability to be careless intermittently? [...] I just think, as a codebase in a dynamic language grows, codebases seem to build lots of tooling to make that dynamic language less dynamic.

I think this is getting closer to the interesting questions. It's often a good thing that when the product matures and moves more into maintenance mode, you can then incrementally add the kinds of rigidness that suits the needs of that. Clojure has excellent support for these in the schema style data validation tools of spec, malli, etc.

If you had a rigid system and slow turnaround from the start, you might not have gotten off the ground to get that far.

> If you had a rigid system and slow turnaround from the start, you might not have gotten off the ground to get that far.

I always see people say this and on the surface it seems to make sense, but I also always wonder what "rigid system" they're talking about. It's much, much faster to make big changes in every phase of a project in Haskell for me than it is in Elixir, so this is the perspective I'm seeing this from. This hypothetical/straw man "rigid system" is hard to fathom.

It's funny - I see that sentiment all the time ("Static typing is slower to get going with") and I kinda chuckle. In both static and dynamic languages, in the beginning, you're not doing anything silly. In both scenarios, you likely aren't writing your methods that accept strings and then immediately trying to pass them ints. For two developers of the same proficiency, competing to generate value in a static vs. dynamic language, I suspect the first 10 hours or so of building a project would progress pretty similarly. Compilers don't really fight with you until there's lots of hidden complexity.*

*Haskell and Rust get a lot of flack because of their compilers being difficult for beginners to work with. I don't necessarily think this is actually an issue - for a sufficiently skilled Rust or Haskell dev, I doubt most compiler errors feel like a "fight".

> for a sufficiently skilled Rust or Haskell dev, I doubt most compiler errors feel like a "fight".

That's certainly true of my experience. I prefer to have the compiler there guiding me (My reference points are poorly-typed languages like C, Java and C++, and the dynamically-typed language Python. I've never used Clojure.).

I don't have Elixir experience, but the natural way to get started in modeling data and state in Clojure quite obviously involves less ceremony and scaffolding than what you do in Haskell, and is less work to change around.

Also, it's not just the amount of work, it's the complexity of the language. Clojure is really simple, so you don't h ave to spend much of your cognitive capacity juggling things related to the language or operating a mental simulation of the type system.

I totally understand what you mean! At least I think I do. I have spent a significant amount of time going down the "type flex" rabbit hole. You can always make thinks a little safer, a little more concise, and so on.

In that sense I really do get off the ground much, much faster in Clojure. In fact, it's my favorite language for prototyping and the whole interactive execution model of the REPL makes we want to learn Emacs and do everything in some kind of lisp, rather than awk, sed, bash, dash, whatever.

I think the key ingredient for me with Haskell is to know when to stop. You can be very productive even as an intermediate Haskell user if you restrict yourself to the features with the highest return on investment. Everything else can be done later. But I also know that it's very tempting to stress out over these details.

As a very late conclusion to my various comments in this thread: if I got better at taming type related errors in Clojure I could very well see it being my go-to language for everything.

Yeah, it seems like programming language decision is, at least in part, a proxy for "At what point do you want to be held accountable for your program's correctness at runtime?"

Haskell/Rust - Immediately

Java/C#/Go - Relatively quickly

Dynamic Languages - Whenever you decide it becomes important

It's a bit of an oversimplification, I think.

Even though Clojure is not a statically typed language, it does have a type system.

Here's an example what Clojure.Spec lets you do. When I was working for a fintech company, we built a suite of specs for a ledger. Based on those specs we could generate data. And it wasn't just some set of key/value pairs with completely randomized numbers. It would generate "a proper" ledger, where every number in a transaction depends on other transactions.

We used that generated data to render UI locally and on the non-prod environments.

Using the same specs we build data validators, we re-used the specs to validate data in the input fields in the UI. Which is totally bonkers. How the heck you achieve code re-use between completely incompatible ecosystems - in our case, JVM and Javascript? Even Nodejs doesn't always let you re-use code between backend and the front. Clojure allows you.

Using the same specs, we've built property based/generative tests.

I've never experienced the joy of creating such robust, predictable, and reliable software with any other (statically typed or otherwise) language before.

I'm not saying you cannot build a similar thing (or even better) with Scala or Haskell (or some other PL). The simplicity of how Clojure allows you to write things like that - just incomparable.

I'm not familiar with Clojure Specs, but it definitely sounds exactly like the "Dynamic language implements type checking tooling to assert correctness", as referenced in the above post. The spec website just looks like type assertions as "validation" - what am I missing?

> Even Nodejs doesn't always let you re-use code between backend and the front.

This is not true. Check out Lodash. It's a dependency of pretty much every FE and BE NPM package that exists. Ignoring rendering libraries like React, client side JS and backend JS are "just" JS.

> I've never experienced the joy of creating such robust, predictable, and reliable software with any other (statically typed or otherwise) language before.

I think you should definitely keep doing the things that bring you joy!

> This is not true. Check out Lodash.

Respectfully, as someone who spent over a decade building front-end apps, I'd say: the code re-use between js in the browser and js in node still feels limited in comparison with Clojure/Clojurescript approach.

I'm not talking about utility libraries.

Because you chose to bake environment information into your code, that does not mean nodejs doesn’t support client/server reuse. Respectfully.

I never said "it doesn't support", it's just not the same.

Code re-use is just one of the aspects. When choosing a tool, especially a tool like a programming language, one needs to take "a holistic approach". Clojure is not a silver bullet. Neither is Haskell, Rust, or any other PL.

I like Clojure today, because today it makes sense for me to use it. For the projects I build. I'm sure, someday, it stops making sense for me to use it, and I will move onto something else.

You can use all sorts of arguments for people to try something else today, assuming they are just misinformed - either about Clojure or the other PLs (you're preaching about).

I can assure you though, most Clojuristas I know - didn't end up using Clojure by accident. It's a deliberate choice. After trying many other options.

Whether you get strong assurance of correctness from static typing depends on your domain, are you're working with a closed-world app like a compiler, or a talking to the rest of the world a lot?

Though it's telling how little static checking by type systems is leveraged eg in LLVM, so even in closed systems the assurance payoff for static checking doesn't necessarily get good bang for the buck.

Eg working with web based services, your code tends to communicate a lot with other services, and a very large % of bugs that make it further out than your dev laptop come from those interfaces. Making these part of the closed world of the static type system is done in some places but most static language users elect not to do it, preferring programmable checks in form of schemas or tests. Which I think tells something.

I tend to think of static vs dynamic as a mindset question, where our bias of loss aversion rears its head. It's an attractive idea to hedge your risks by usign a static language even if it only catches the trivial bugs and slows you down, because statically found bugs are a falsifiable observation, wheras making programming easier, faster and more fun[1] in general doesn't leave hard evidence unless you run duplicate trial projects just for science.

[1] For some personalities, you might derive more fun and satisfaction in the mathematical certainty of static languages. Or you might be in a work environment where you don't have room to find fun anyway. Or maybe you don't even like programming. Yet others find fun indispensable: fun is necessary for keeping up morale.

> Eg working with web based services, your code tends to communicate a lot with other services, and a very large % of bugs that make it further out than your dev laptop come from those interfaces. Making these part of the closed world of the static type system is done in some places but most static language users elect not to do it, preferring programmable checks in form of schemas or tests.

Are you actually suggesting that "most static language users elect" to not decode at the boundaries of their system because it somehow is favorable to not do so? This does not match my perception of things, neither the "most are not decoding" part nor the "it's fine to not decode into a known good structure" part.

> It's an attractive idea to hedge your risks by usign a static language even if it only catches the trivial bugs and slows you down, because statically found bugs are a falsifiable observation, wheras making programming easier, faster and more fun[1] in general doesn't leave hard evidence unless you run duplicate trial projects just for science.

What an incredible straw man you've built up, but then you just let it sit there and don't even burn it up.

Since I'm not here to convince anyone, I can say your straw man is the opposite of my experience. I've never been able to prototype and change a system in any phase of its lifetime faster than I've been in Haskell. Haskell has downsides, but speed of development and maintenance is one of its strong points.

> I tend to think of static vs dynamic as a mindset question, where our bias of loss aversion rears its head.

> Since I'm not here to convince anyone, I can say your straw man is the opposite of my experience. I've never been able to prototype and change a system in any phase of its lifetime faster than I've been in Haskell. Haskell has downsides, but speed of development and maintenance is one of its strong points.

Yup, and when it comes to fun, I've never had more fun programming that in Haskell, where I let the compiler check the annoying fiddly bits so my brain is free to tackle the meaty problems!

> Are you actually suggesting that "most static language users elect" to not decode at the boundaries of their system because it somehow is favorable to not do so

I'm was thinking protocol meta systems like protobufs where you use tooling to enforce closed world style communication patterns in a networked world.

I don't particularly want to argue with you. Using the phrase "falsifiable observation", and then referencing "fun" as an argument just doesn't really work for me. I appreciate that you like dynamic languages, but I will not take your "rest of the world" bait. To suggest that dynamic typesystems are as verifiably correct as static typesystems is verifiably incorrect.

Not sure if this needs clarifying or not from your message but:

By falsifiable I meant that it's an observation that could be shown to be false, if it was false. So a concept from philosophy of science, not an assertion.

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