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Why Clojure?

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Re: Why Clojure?

#101

Post by hcarvalhoalves »

Qerub wrote: post #91

I might be damaged from years of Java, but my main imagined issue with Clojure is the lack of a component system. Call it OCaml functors or OOP classes, but instantiating a component with replaceable components as input is what I personally need for large scale programming. To make things more concrete, let's say you are writing an integration to another system using HTTP. On the surface you'll have functions like `f…

Why is a library a "band-aid", and why is it necessary to have such feature in the core language?

Re: Why Clojure?

#102

Post by hcarvalhoalves »

kbd wrote: post #94
kllrnohj wrote: post #87

The response to "but is it slow" is pretty disappointingly bad. > No. Clojure is not slow. Oh, look, it’s not C. It’s not assembler. If nanoseconds are your concern than you probably don’t want Clojure in your innermost loops. You also probably don’t want Java, or C#. But 99.9% of the software we write nowadays has no need of nanosecond performance. I’ve built a real time, GUI based, animated space war game using Clo…

The biggest thing keeping me from ever seriously learning Clojure is the JVM. Slow startup time means I'd never use Clojure for "scripts", and I certainly don't want to have to manage the JVM in production scenarios, so when would I use Clojure? If there was a native version that could produce static binaries like Go/Nim/Rust I'd be much more interested to learn it.

Lately GraalVM can be used to compile a native binary, since Clojure compiles down to Java bytecode.

https://www.innoq.com/en/blog/native-clojure-and-graalvm/

Sometimes the trade-off of slow startup vs. having a JIT'ed VM is better, since you get a lot more performance, if you're working w/ long-lived processes.

Re: Why Clojure?

#103

Post by scythe »

kbd wrote: post #94
kllrnohj wrote: post #87

The response to "but is it slow" is pretty disappointingly bad. > No. Clojure is not slow. Oh, look, it’s not C. It’s not assembler. If nanoseconds are your concern than you probably don’t want Clojure in your innermost loops. You also probably don’t want Java, or C#. But 99.9% of the software we write nowadays has no need of nanosecond performance. I’ve built a real time, GUI based, animated space war game using Clo…

The biggest thing keeping me from ever seriously learning Clojure is the JVM. Slow startup time means I'd never use Clojure for "scripts", and I certainly don't want to have to manage the JVM in production scenarios, so when would I use Clojure? If there was a native version that could produce static binaries like Go/Nim/Rust I'd be much more interested to learn it.

By contrast, one principal reason I started learning Clojure was ClojureScript. Making stuff that can run in the browser or as a browser extension is awesome for cross-platform compatibility.

Re: Why Clojure?

#104

Post by nimih »

yakshaving_jgt wrote: post #65
mbrodersen wrote: post #10

I played around with Closure for a while to learn its cost/benefits. It is basically the love child of Lisp, Haskell and Java. So it introduces nothing new to the world. However it is certainly an interesting mix that some developers like. And Rich Hickey is an entertaining speaker/presenter/seller of Clojure. Even if you don't care about Closure, watch his talks on YouTube.

Clojure has nothing at all to do with Haskell. I can't think of two more opposed camps in programming.

You're right, one is a language with a data-structure-centric approach to problem solving and an emphasis on pure transformations of immutable nested trees and lazy sequences, and the other one forces you to learn the word Monad.

Edit: Joking aside, I do think you're right in terms of the ideological foundations and organizational structures of the two languages (clojure's emphasis on practicality, curation and evolution of the core library+language by a single BDFL, compared to haskell's origins in PL research and democratic design/maintainence), but in practice I think a lot of that comes out in the wash--dynamicism vs. static typing is definitely a huge difference, but there's a lot more to language design and the material practice of building software than whether your compiler reads type signatures, and I think that along those axes, especially when compared to other mainstream programing languages/ecosystems, clojure and haskell end up being pretty close.

Re: Why Clojure?

#105

Post by badsavage »

yakshaving_jgt wrote: post #90
badsavage wrote: post #84

Earlier quoted context omitted.

Clojure has something like an extendable type system called Spec. We can create our own types lol

I am quite familiar with Spec. In my few years of professional Clojure experience, working with people who write Clojure every day, and enjoy it, and advocate using things like Spec, I have never actually seen anyone do it successfully in practice. I understand the idealist world view is seductive — we'll be discipined, we'll write the tests, we'll make good use of Spec, etc etc. In reality, I have never seen this ha…

Basically you says if a type system is optional, people tend not to use it, because most of the times they are good without it.

I agree.

But we do use spec very successfully for complex data structure validations and example data generation.

Re: Why Clojure?

#106

Post by yogthos »

mabbo wrote: post #93

> 1. Economy of expression Funny, this list is the same one I use as to why I'm so annoyed with Clojure right now. I inherited a mission-critical Clojure ML library my team uses for it's primary business goals. It was written 4 years ago by a research scientist- who quit 3 years ago. We know what it's supposed to do. We know that it seems to do the job well. We just can't understand the code well enough to be certain…

This is true literally for every language out there. My team maintains a Java application from over a decade ago. It's an utterly incomprehensible mess that nobody understands, and it's incredibly difficult to make any changes to the project.

It's not the job of the language, but rather that of the developer to write clear and readable code.

This problem is addressed by using good design practices, code reviews, testing, and documentation.

Re: Why Clojure?

#107

Post by 6thaccount2 »

amelius wrote: post #95
invalidOrTaken wrote: post #45

Earlier quoted context omitted.

Not the grandparent, but I realized the other day that I'm at nine years of clojure, so... What's made clojure so great, imo, is its unicorn status as a principled-yet-practical language. That "principled" part is not worthless---it means that a lot of great minds are drawn to it. Before react took over the world, clojure folks were already taking steps in that direction. A lot of other things. The "sequence" as a co…

What is GUI programming like in Clojure? What libraries exist, and what paradigms are used? E.g. is it more like React or is it more like Gtk/Qt?

There is a swing example on the getting started page (or there was a few years ago). It was a one liner to have a Swing pop up say "hello world" or something like that. I'm not sure how easy it is to write actual apps that way.

Re: Why Clojure?

#108

Post by 6thaccount2 »

LandR wrote: post #57
heartofgold wrote: post #46

Earlier quoted context omitted.

Not original poster, but my take is: - Immutable data-structures with concise literals for lists, vectors, maps, and sets. Having pure functions and immutable data-structures makes code easier to reason about, easier to test, and thread-safe. (But clojure doesn't "force" you to be pure. The idea is that you write as much of your code in pure functions as you can, and push the IO and impure parts to the extremities. I…

The above posters point on Homoiconicity is a big one, here is a quick (and silly) example for anyone unfamiliar with the term. Take the following clojure: (+ 1 2) => 3 Here the ( ) delimits, a list, and as the blog post says most lists are function calls. In this case the function is + and it's params are 1 and 2. It means if we do this (1 + 2) We get an exception that 1 isn't a function... However, we can tell Cloj…

Why not just do that as a function though? Why use a macro?

Re: Why Clojure?

#109

Post by mbo »

scythe wrote: post #103
kbd wrote: post #94

Earlier quoted context omitted.

The biggest thing keeping me from ever seriously learning Clojure is the JVM. Slow startup time means I'd never use Clojure for "scripts", and I certainly don't want to have to manage the JVM in production scenarios, so when would I use Clojure? If there was a native version that could produce static binaries like Go/Nim/Rust I'd be much more interested to learn it.

By contrast, one principal reason I started learning Clojure was ClojureScript. Making stuff that can run in the browser or as a browser extension is awesome for cross-platform compatibility.

If you like "functional and runs on the JVM" you might like ScalaJS too. It's a mature transpiler, and the community has rallied to ensure that all the important libraries compile both to the JVM and to JS.

Re: Why Clojure?

#110

Post by zimablue »

6thaccount2 wrote: post #108
LandR wrote: post #57

Earlier quoted context omitted.

The above posters point on Homoiconicity is a big one, here is a quick (and silly) example for anyone unfamiliar with the term. Take the following clojure: (+ 1 2) => 3 Here the ( ) delimits, a list, and as the blog post says most lists are function calls. In this case the function is + and it's params are 1 and 2. It means if we do this (1 + 2) We get an exception that 1 isn't a function... However, we can tell Cloj…

Why not just do that as a function though? Why use a macro?

You couldn't write it as a function, unless you pass in the 1+2 part to an outer function (macro) as either a list of arguments (1, math.add, 2) or a string (+you have an eval fn).

At that point you're emulating lisp without the elegance, and the first approach is only possible because functions are first class objects. If you were trying to rearrange an expression that had control flow or keywords in it (eg. Modify the behaviour of an if) then you would have to reify the "if" (change the original code so it had a class to represent the if not use the keyword). So you're kind of reinventing lisp by wrapping every part of your language as an object

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