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Comment by catfacts

2 days ago

I remember Clapp a Common Lisp in C++ using LLVM. Clapp was promising but progress has been very slow. Since Clojure is similar to CL, one wonder if Jank will experiment similar problems. Might I ask the author of Jank whether he knows about Clapp and if so, how will this project try to avoid getting stagnated?

Edited: Here is a post in HN from 2014 about Clapp. https://news.ycombinator.com/item?id=8367404

In that post and comments we read that Clapp was 100x slower that sbcl, and the author of Clapp claimed: "LLVM is a great library for implementing C and C++ but more work needs to be done to support Lisp features like closures and first-class functions. We are working on that now".

I hope Clapp's author work in the last 11 years could help today efforts. Surely, the LLVM of today is not that of 11 years ago. Anyway, IMHO, sharing some knowledge could be productive for any project that is about C++, Lisp or Clojure using LLVM.

If I recall correctly, compiling Clapp takes a full day, that gives not a good vibe.

On the happy path, I think that Julia transpile to LLVM, but Julia is the result of many men working years at it. Honestly, I don't think that one single programmer to be able to create such a big project as a performant clojure in C++ will the ability to compile code quickly. Getting sbcl speed and compilation speed would be an extraordinary feat!

In Go there were great sacrifices to get fast compilation, and the problems to include generics, trying to avoid blows up compilation because some type checking is NP-complete.

Also perhaps ECL, a lisp in C, can gives us some hints about how to get better performance and compilation speed.

Perhaps I am just too old to be open to new dreams, anyway I hope the best to this project and I thank to Clojurists Together for supporting this project. It must be very intellectual rewarding to work in a project whose aim is to extend and improve your favorite computer language. But the journey will be no an easy one, that's for sure.

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catfacts

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Jeaye  2 days ago

> Might I ask the author of Jank whether he knows about Clapp and if so, how will this project try to avoid getting stagnated?

I'm aware of Clasp and have spoken with drmeister about it in the early days of jank. Ultimately, jank and Clasp differ greatly, not only in that jank is Clojure and Clasp is Common Lisp, but also in their approach to C++ interop.

> If I recall correctly, compiling Clapp takes a full day, that gives not a good vibe.

I'm not sure about Clasp's compile times, but C++ is slow to compile, in general. The jank compiler itself builds from nothing in about 1 minute on my machine. We've yet to see how the jank compiler will handle large Clojure project, but I do expect it to be slower than Clojure JVM.

> In that post and comments we read that Clapp was 100x slower that sbcl

That's an old post, so I'd expect that Clasp is faster now. I can say that jank is not 100x slower than Clojure JVM, in my benchmarks.

> Perhaps I am just too old to be open to new dreams, anyway I hope the best to this project and I thank to Clojurists Together for supporting this project. It must be very intellectual rewarding to work in a project whose aim is to extend and improve your favorite computer language. But the journey will be no an easy one, that's for sure.

Thanks for the interest and kind words. It's not easy, but it's doable!