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Comment by tastyminerals2 | Hacker News Reader

I have to admit, several years ago, a colleague of mine advised me if not to try Clojure but at least to read the "History of Clojure": https://dl.acm.org/doi/pdf/10.1145/3386321, which I never did. But one day I decided to watch Rich Hickey - Greatest Hits https://changelog.com/posts/rich-hickeys-greatest-hits... I then read the "History of Clojure", and then jumped into learning it. This is probably one of the most fun languages to build with and one of the most beautiful ones. If not syntax-wise, rather in a way it allows you to express your thoughts via good design and composition that so nicely tickles your brain. If you are still searching for that one shiny tool, and none of them clicks, maybe try Clojure. It's one of the most concise and yet powerful languages I've seen.

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I got what you described by learning Common Lisp just a few months ago. Do you think learning Clojure would get me something in addition to that or is it roughly the same?

Depends on your style of programming CL. Clojure is immutable by default with a heavy emphasis on concurrency and strong ties to the JVM as its host environment. The differences you’ll find mostly lie in those areas.

IMO, Clojure is superficially/syntactically much more elegant and beautiful than Common Lisp or Scheme. I find this really helps you focus on what matters most.

Besides the superficial syntax, those are some differences pointed out by (common) lispers: https://gist.github.com/vindarel/3484a4bcc944a5be143e74bfae1...

really good talk from Rich Hickey: Clojure for Lisp Programmers - https://www.youtube.com/watch?v=cPNkH-7PRTk&t=3837s

I think Clojure leans into immutability a lot, and that leads to more interesting APIs and norms that are valuable. CL has always felt a bit more.... "running on a machine" that I feel has less of a place in an era where everyone and their dog has functional programming essentials built in.

Clojure is interesting, but some Clojure APIs (stuff like Spectre) is "I want this everywhere now" stuff.

> Do you think learning Clojure would get me something in addition to that

For me, the biggest benefit is that it's hosted. Learning only Clojure, I can easily today write for JVM, .NET, JavaScript, Flutter, or shell scripts. Even when I need to write Lua, I'd usually pick Fennel. It's not Clojure but feels very similar. There are libs that can give you Python or R interop from Clojure. There are projects to target Golang, Rust or Erlang. Jank is a super interesting, experimental implementation of Clojure that runs on LLVM, I'm very excited about it. Do you want to become a true polyglot programmer? You only need to learn Clojure.

>For me, the biggest benefit is that it's hosted...I can easily today write for JVM, .NET, JavaScript, Flutter, or shell scripts.

Isn't CL better for this? You are not bound to some VM and you can produce native binaries.

I can't really say. I know you can (for example) use LispWorks to write CL for mobile, targeting both - Android and iOS, but I think there would be greater friction to keep it cross-platform, each platform's nuances would have to be handled differently, it's not going to be very unified codebase (I think).

Clojure also teaches you functional programming, where-as CL only teaches you the LISP beauty. Clojure teaches you both Lisp and Fp. So the FP part should still be worth it even though you got the Lisp part from CL.

How does fp in clojure differ from fp on common lisp?

Clojure has immutability built into the language and the core data structures are all persistent so that you can get sufficiently efficient partial updates while still preserving a pure FP style.

Furthermore, the data structures in clojure also have interfaces that make it easier to swap out which data structure you're using while still keeping whatever map/filter/reduce algorithm implementation you're sending it through.

Common lisp, on the other hand, has setf. Which more or lets you mutate anything. You certainly can code in an FP style in common lisp, but it doesn't restrict you in any meaningful way. Not a problem if you control the entire codebase, but when gluing components together this can be a source of friction.

FP in CL is kind of optional, and it's also more in the sense that you can pass functions as arguments or return functions, meaning FP == First Class Functions.

But in Clojure, FP is kind of mandatory, there's no OO for example, and it's more than just first-class functions, it's also immutability.

Clojure uses immutable lists, vectors, hashmaps, and sets. Also it has syntax sugar such as [1 2 3] for vectors, {"Jan" 31 "Feb" 28} for hashmaps, #{1 2 3} for sets, and much more. Also it has multimethods which are even more generic than CLOS.

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