Comments on: The 8 Most Important Haskell.org GSoC Projects

By: Brandon Simmons

Brandon Simmons — Mon, 05 Apr 2010 20:24:50 +0000

Hackage 2.0 is a brilliant idea. I want to be able to search hackage with hoogle’s interface, including searching for package’s that export a function with the type signature I search for.

By: David Waern

David Waern — Fri, 02 Apr 2010 14:23:52 +0000

A student has proposed marrying Haddock with Pandoc to create something similar to Python’s documentation system Sphinx. The idea is to be able to write general documentation, and not just API documentation, and to be able to use e.g. Markdown.

This could help us write friendlier, more example- and tutorial-driven documentation tightly integrated with API documentation.

If someone would like to mentor this, the student’s email address is alvivi@gmail.com.

As the maintainer of Haddock I’d be able to help out, but not be the primary mentor since I may be too busy this summer.

By: Simon Marlow

Simon Marlow — Fri, 02 Apr 2010 11:39:53 +0000

If people aren’t finding the GHCi debugger is up to the job, maybe a SoC project to address the most important issues there would be a good idea?

On the topic of ThreadScope, there are some more ideas in the ThreadScope TODO list:

http://code.haskell.org/ThreadScope/TODO

By: ja

ja — Fri, 02 Apr 2010 02:21:44 +0000

http://ww2.cs.mu.oz.au/~bjpop/buddha/

I miss the Buddha debugger. With it, you just called the buggy function on inputs known to cause the bad behavior. It then refined the input to determine what functions your original function would call, and with what arguments. For each of these, it would ask you if the input/output pair was valid. If not, it would explore that child function further.

It was sort of a tree search on your function call graph. It no longer works on GHC, and hasn’t for ages.

It really showed how referential transparency made coding easier. It was, in fact, the best debugger I’ve used in any development environment for any language.

Oh well.

By: Ivan Miljenovic

Ivan Miljenovic — Fri, 02 Apr 2010 01:49:03 +0000

I’ve actually been considering porting pretty (or another pretty-printing library) to using Text for use with graphviz, so that I can control which encoding is being used, etc.

As for the test project: I doubt this will magically solve the QuickCheck dependency issue: if developers can’t use a compile-time flag to bring in optional usage of QC for testing, then why will they do so just for a specified Cabal option?

By: sclv

sclv — Thu, 01 Apr 2010 23:23:28 +0000

On the main topic, Cabal test would be awesome. Especially since it would let us solve the notorious quickcheck dependency problem and also maybe the hiding vs. exposure dilemma in a uniform way.

Hackage 2.0 would similarly be super important. There’s a host of issues with the growing ecosystem, and we need to sort them out. The ticket seems fairly modest, but I guess until we get that far, then all the more blue-sky features like tagging, community feedback, etc. aren’t even on the table.

By: sclv

sclv — Thu, 01 Apr 2010 23:07:18 +0000

Andy: For now I just use ndm’s Safe religiously and import prelude without the unsafe functions entirely. 90% of the time I’ll get pushed into handling the failing case correctly, and when I’m convinced that it should “never” happen, then the custom error from headMsg points me where I want to go.

By: Edward Kmett

Edward Kmett — Thu, 01 Apr 2010 22:55:30 +0000

At least one student who has more than passing familiarity with LLVM, (Csaba Hruska, IIRC), has proposed tackling writing LLVM optimization passes in Haskell itself.

And another, Alp Mestanogullari, has been talking to Davie Terei about ways to speed up the execution of the LLVM code gen.

Overall, I think there are a lot of good candidate projects for this year’s summer of code.

By: dons00

dons00 — Thu, 01 Apr 2010 19:56:36 +0000

Yes, proposals are open. Log in to the trac and open a new proposal ticket here: http://hackage.haskell.org/trac/summer-of-code/newticket

By: Andy Gill

Andy Gill — Thu, 01 Apr 2010 19:55:06 +0000

Thanks Don. When debugging imperative programs written in Haskell, we’ve got a good handle on that. But for real functional programs, debugging is just hard.

This month, I’ve hit <>, and ‘head []‘ many times. I needed to pull out hpc-strobe to help debug it, which is just wrong!

Are the proposals still open? I could propose a small tracing debugger, that just tells you where you’ve just been? That would help.