Haskell on JVM?

Question

I'm wondering if there is some way to make Haskell run on the JVM (compiled or interpreted)?

There exists JHaskell on Sourceforge but this one seems to be empty and dead.

GHC uses LLVM as compiler backend. Would it be a good idea or possible to compile LLVM to Java bytecode? Or maybe use a different compiler backend?

Tail call optimization still seems to be an open issue. That is why other functional jvm languages like Clojure need special constructs (recur). — jeha
@jeha: Nah, TCO is easy. Seph does it, Erjang does it, Kawa and all the other Scheme implementations on the JVM do it. The JVM has Exceptions, which are basically the same as GOTO, which can be used to implement TCO. Or you use trampolines. Or you don't use the JVM call stack at all and just implement your own. The reason why Clojure and Scala only provide limited TCO (basically, only tail recursion is optimized) is because they want to use the JVM call stack for interoperability and performance reasons. As Rich Hickey, Clojure's designer said: Interop, speed, TCO -- Pick two. — Jörg W Mittag
I can't imagine it would be hard to compile Haskell to the JVM if you did not care about performance at all and only focus on what the Haskell language requires. Use trampolines as Jorg mentions. They are easy to implement. Use the simplest data structures that do the job. Don't bother optimizing. I'm sure someone could hack up a working and full implementation within a week by himself if he actually cared. — Thomas Eding

Daniel Pratt Daniel Pratt · Accepted Answer · 2011-09-16T19:49:05

You may want to investigate Frege. Quoting from that page:

"Frege is a non-strict, pure functional programming language in the spirit of Haskell."

"Frege programs are compiled to Java and run in a JVM."

Based on a brief perusal of the language specification, Frege looks to be nearly a Haskell clone. Perhaps the phrase "in the spirit of Haskell" is simpy intended to set the proper expectation.

Haskell on JVM?

4 Answers