4ever-clojure VS reagent

I found this to be an awesome bridge between reading about the theory and actually writing code that works: https://4clojure.oxal.org/

This is for general Clojure, I’ve had a lot of fun and learned a lot from it (and the original): https://4clojure.oxal.org/

It's normal to apply methodology like this to clojure when transitioning from other languages. When I was first learning I did a bunch of exercises on 4clojure and my first attempts looked like this. Then I found loop from the standard library and I understood immutability but relied on loop to do anything to collections of things. Eventually, after looking at the answers, I started to get familiar with the standard library. Then my solutions started to look like the two line solution above.

4Clojure is here now: https://4clojure.oxal.org/. It runs locally in your browser.

Go to https://4clojure.oxal.org/ and solve some stuff. And don't learn any theory. You're thinking how a C# developer thinks and you think you need to learn some kind of packages by heart or something.

I learned by reading through a book, then working through problems on https://4clojure.oxal.org/. If you've got JS experience it won't take too much effort to pick up. Don't get too carried away with forming the perfect tail recursive pure functional monad or whatever. Get into just doing what you're trying to do quickly, then after you're competent, read other people's code to correct your style.

I'm only a couple months into learning Clojure too, but I found solving a problem myself and then seeing others solutions on this website https://4clojure.oxal.org/ was invaluable for learning to think like a clojurist.

I'm trying to learn Haskell and found https://4clojure.oxal.org/ very helpful. https://tryhaskell.org/ was also nice, but it is limited in scope as compared to its Clojure equivalent.

The actual address is https://4clojure.oxal.org/

Generating `HTML` from lisps has poisoned any other approach for me, see for example https://www.neilvandyke.org/racket/html-writing/, https://reagent-project.github.io/, and https://edicl.github.io/cl-who/

Hiccup syntax for Clojure uses hash maps (curly braces) for attrs, e.g. `{:style {:background "red" :margin "1em"}`

See Reagent which uses Hiccup synta: https://reagent-project.github.io/

    (defn simple-component []

* Single-Page App: shadow-cljs for the build concerns (https://github.com/thheller/shadow-cljs), Reagent with Re-frame for complex/large app (https://reagent-project.github.io and https://github.com/day8/re-frame). Even if we now prefer using HTMX (https://htmx.org) and server-side rendering (Hiccup way of manipulating HTML is just amazing, https://github.com/weavejester/hiccup).

The API documentation lists the most commonly and rarely used parts before going into detail and there are many usage examples.

Reagent has a nice intro tutorial (classic todo-app): http://reagent-project.github.io and many other helpful tutorials and resources for beginners: https://cljdoc.org/d/reagent/reagent/1.2.0/doc/documentation...

However, since Reagent is still stuck with class-components for more complex behavior and relies on Hiccup, which is nice but has a performance cost compared to pure React, I am unsure about its future. Like some others in the Clojure community, I have moved to thin React wrappers like Helix and use Refx to integrate those with re-frame. It may be a bit confusing right now for beginners since there is no “golden path”.

Also, unfortunately, many smaller libraries are poorly documented and it seems like it is expected from the developer to dig into the source code to find out what’s going on.

What I found the most difficult as a beginner was how to setup a project in ClojureScript in the first place, like all the configuration in shadow-cljs, how it interacts with deps.edn, how it integrates with npm, the REPL, etc. But dev/build config has always been a weak spot for me, so it might be just that.

Overall, I still very much enjoy working with Clojure(Script), more than in any other language. Anyone who likes Lisps and functional programming should give it a try (and be sure to watch Rich Hickeys amazing talks!).

have you tried cljs and reagent? it’s a different vibe.

my bootstrap: https://github.com/nathants/aws-gocljs

the project: https://reagent-project.github.io/

Clojure people have been doing this for a decade or so. It’s really so much better to work with. All started with Hiccup and when React came along you got Reagent and many more developments building on the idea.

> But Reagent supports functional components as well, with hooks and all.

I addressed this already: while reagent is able to emit function components, there is a performance penalty to this.[1]

> I also very much like Hiccup, and so do many of us, because code is data and data is code, and Helix has decided not to support that.

Hiccup is convenient to write, but it is a constant run-time cost and a significant storage cost given that you have to store long series of constructors to cljs.core.PersistentVector in your bundle, have the JS runtime actually construct the vector, then pass it through a Hiccup interpreter to finally produce DOM nodes and throw away the persistent vector, only to repeat this entire process again on re-render.[2]

> Helix has decided not to support that.

That is simply not true. From the Helix documentation[2],

> If you want to use libraries like sablono, hicada or even hx hiccup parser, you can easily add that by creating a custom macro.

These are all Hiccup interpreters you can readily use.

IME there is very little difference between using the $ macro in Helix and writing Hiccup. I do not really miss Hiccup when I use Helix, and you still have data as code ;)

While this is from an unrelated project, there are benchmarks[3] done against Reagent that demonstrate the sheer overhead it has. In practice it is not a big problem if you rarely trigger a re-render, but otherwise it is a non-trivial cost, and if you want to use modern React features (like Suspense), there is a lot of r/as-element mingling going on, converting cases, etc. that simply make Reagent feel more tedious to use than Helix.

Also, the newer UIx2, which largely borrows from Helix, is "3.2x faster than Reagent" according to one of the contributors.[4]

I think it'd be worthwhile to benchmark all of these libraries against each other and record the data in one place. Maybe I'll get around to doing it this weekend :)

---

[1] https://github.com/reagent-project/reagent/blob/master/doc/R...

[2] https://github.com/lilactown/helix/blob/master/docs/faq.md#w...

[3] https://github.com/roman01la/uix#benchmarks

[4] https://github.com/pitch-io/uix/pull/12

Reagent is peak React. All the good stuff without any of the hook and readability problems the article describes.

No affiliation, happy user for years.

https://github.com/reagent-project/reagent