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Comment by huahaiy | Hacker News Reader

If you write your code the correct way, there wouldn't be any states in your namespaces for you to keep track in your head. That only happens if your code is full of `(def some-state (atom {}))` or something like that.

You are basically illustrating my point about "You probably cannot learn Clojure all by yourself". You need a mentor to show you how to do Clojure correctly, or you have the humility to learn the proper Clojure way. Sadly, most people would rather just try something and jump onto conclusions immediately.

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Function definitions and vars are a form of state that can accumulate in a REPL session. Its not just atoms.

This can lead to issues where you decide to refactor and rename a var (Clojure is all about concise and expressive names, so its not uncommon to do this.. At least not for me) but you might not catch every place the old var name is being used. Because both vars are still exist in the state of your REPL, everything seems to work, but once you compile your uberjar or whatever, things are broken.

A REPL isn't a replacement for good unit tests, and there are techniques for reloading your REPL state on save, but the issue of needing to keep the "REPL state in your head" is real, and not an artifact of doing things wrong. Just something that the developer needs to be aware of as a potential hiccup in the REPL experience.

> If you write your code the correct way,

Then you don't need a REPL. This is a very weak argument, overall: there are programming techniques to compensate for any deficiency in the environment. The fact that you need to use them is already worse than not having to worry about it at all.

> Sadly, most people would rather just try something and jump onto conclusions immediately.

Just a gentle reminder, you're not talking to "most people" here. Nevermind me, we [EDIT: cut out the irrelevant details] I just want to say that assuming good faith and informed criticism are the better defaults for this forum.

Repl development is great for exploration, when you don't quite know the right representation of your problem yet.

The alternatives isn't changing your development environment, it's writing on a white board

Nobody said you "need" REPL. Doing REPL driven programming is just more productive, hence it is considered the right way in the Clojure community. Heck, you don't even "need" any higher level languages, you can write code in machine code, but that's besides the point.

Your boast about your Lisp credentials is exactly the kind of things I caution against in the article. Your pride has prevented you from properly learning Clojure, which has a very different programming style from other Lisps.

You are basically illustrating my point live, again.

> Nobody said you "need" REPL.

Well, you did, quoting the article:

> Yes, if you are not using the REPL, you are not doing Clojure right.

or should I understand this another way?

> but that's besides the point.

True. I'm saying that if you need to code in a particular way to make good use of the REPL, then it's already worse than being able to use the REPL well without any special coding style. Erlang and Elixir are great examples of that.

I also have a problem with you believing there even is one correct way to use any language, but that's bearable. You being so sure that you're the only one qualified to know anything about that correct way is much worse.

EDIT: I just saw so many "revolutionary ways to write code" which were being pushed hard by people absolutely sure their methods are so much better, and which ultimately amounted to little more than a few percent improvement in productivity in the real world - in the best case. It makes me suspicious of any such claims.

> Your boast about your Lisp credentials

My? I said:

> Nevermind me, but [...]

So you're putting words in my mouth; further, I said nothing about my knowledge of Clojure, so this:

> Your pride has prevented you from properly learning Clojure

Is completely unwarranted. And offensive. Could you please stop?

Then it is actually far worse than what I guessed. You know next to nothing about Clojure, but somehow feel that you are qualified to have an opinion about it. That doesn't look good, does it?

What opinion about Clojure?! Where? You're jumping to conclusions without any basis, while trying to caution others not to jump to conclusions?

I'm talking about the general ease of use of features in programming languages. If you need to code in a particular way to use a feature, then it's harder to use than if you didn't have to do this. Is that wrong? Could you provide any argument on why is it wrong? And yes, I use Clojure's REPL as an example, and give Erlang as a counterexample. Do you know Erlang? Are you able to compare? If yes, why don't you write about how you see that comparison?

Instead of, you know, childishly fixating on things I never said. For your information, I do know more than "next to nothing" about Clojure. But you won't believe me either way, will you?

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