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Comment by skissane | Hacker News Reader

Clojure is more than just a Lisp for the JVM – it is a Lisp for the JVM with a big focus on immutable data structures – whereas traditionally most Lisps put mutability first instead. There are other Java-based Lisps, such as Armed Bear Common Lisp (ABCL), which are more traditionally Lisp-like in this regard. I think Hy is more of a traditional Lisp, since it shares Python's native focus on mutable data rather than trying to foreground immutability.

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That! Clojure is an elegant experiment with immutability. The implementation details of Clojure's datastructures are a pure joy to look at. JVM is an unfortunate choice as I see it, but it's a pretty solid system which is benefiting from decades of research on JIT, GC, etc, so not entirely unreasonable as a back-end.

I have few good things to say about Python, other than it sort of works. I classify it in the big-sack-of-stuff languages, along with Perl and shells. Not much elegance or style.

Clojure is definitely more than an experiment. It processes many millions of dollars daily through things like banks and even at Walmart. It might not be used a lot, but experiment is not accurate at all. You didn't flesh out your comment about Java, they used to also transpile to C# and still to Javascript. I think Java's fast memory allocator is particularly suitable to the immutable data structure memory requirements. I also find the JVM a very robust and mature platform. It's also a great gateway being able to interop into corporate environments as a way to get traction. I am curious what other language you think would be better given those desired traits that Hickey designed for.

There's also CLOJERL - Clojure on BEAM (Erlang), and recently CljDart, clojure to dart transpiler was released and seem to have a lot of momentum.

Let’s not be too pedantic, it was just an analogy, not a bad one, nor perfect but none are.

As a Clojurist I think it behooves us not to put on gatekeeping airs (because we’re up against those too).

I wasn't trying to gatekeep anyone (and I make no claim to be a "Clojurist"–my Clojure experience is rather minimal). I was making a point about categorisation, taxonomy.

There is a certain category of Lisp-like languages – of which Hy, Fennel and LFE are good examples – which take an existing language, and provide a Lisp-like syntax for it, but generally keep the semantics reasonably close to that of the underlying language. Beyond the syntax, the other main addition tends to be a Lisp-style macro system. Maybe we might call them "veneer Lisps", since they put a Lisp veneer on another language, but beneath the surface it is largely the same.

Clojure isn't a veneer Lisp, because its semantics are quite different from Java – Java is primarily about mutable data, and Clojure-style immutable data structures aren't the mainstream Java approach. A JVM Lisp which dropped Clojure's emphasis on immutability could be a veneer Lisp. Armed Bear Common Lisp and Kawa Scheme are examples of mutability-oriented JVM Lisps, but they don't belong to the category of veneer Lisps either, since they are ports of pre-existing languages to the JVM, and their mutability comes from those pre-existing languages not a desire to conform to Java/JVM semantics.

I'm not saying there is anything wrong with immutability, or that Clojure's focus on it is a mistake, or that one ought to either prefer (or avoid) "veneer Lisps": I'm attempting descriptive taxonomy, not prescriptivism.

i know it's not a full fledged thing like clojure, but it never had that scale in mind either. I should have added a modal in my comment above :)

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