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Comment by dikaiosune | Hacker News Reader

I like the aesthetic of using Clojure to fix Java.

Like many, I have fun using Clojure but during the day I have to pay bills by using Java :D

Jokes aside I think that Clojure is fantastic to manipulate data quickly. By the way this project is built on top of Javaparser (https://github.com/javaparser/javaparser) and that is written in Java.

Small standalone command-line tools are a good place for a language like that, although it's a shame Clojure takes so long to start.

as a workaround we created the interactive mode in effectivejava. Also because parsing tons of files require a lot of work and you probably want avoid redoing it for every query

The nice thing about Clojure development is that you really only need to start the JVM once, after that, you can eval anything you need instantly. And really, startup times aren't that bad. Here's Travis CI for a small project I made. Time to start the JVM and run tests? 2.76 seconds. The entire build completes in ~12 seconds.

https://travis-ci.org/film42/rinok#L99

How is three seconds to run tests on a "small project" "not that bad"?

well, it is not that bad because as part of the tests it also parse all the code of Javaparser and spring-jdbc (by no means small projects). Parsing it is an expensive operation also because the Java grammar is quite ambiguous

What kind of hardware are you running on?

You're pretty much able to keep REPLs open for days if you wish, so if you amortize that 3 second startup over a week, it's not all that serious.

That said, fair point, faster startup is always better.

I just recently saw a story about using a pseudo-static compiler to improve the Clojure startup time. Maybe it's about to get better?

Were you perhaps talking about this article [0]? If not, it's a good read about the state of Project Skummet and improving Clojure load times on Android.

[0]: http://blog.ndk.io/2015/04/23/state-of-coa.html

Yes, that's the one. I came away thinking that I'm still not too interested in developing for Android, but that any tool to reduce Clojure/JVM startup times is promising.

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