Welcome to issue 93 of HWN, a newsletter covering developments in the Haskell community.

Community News

Congratulations to Ganesh (aka Heffalump) and Amanda on the birth of Alexander Suresh Kerr Sittampalam!

Announcements

bustle-0.1. Will Thompson announced the release of Bustle, a tool to show diagrams of D-Bus traffic for profiling purposes. It consists of a small C executable to log traffic, and a Gtk+ application which draws diagrams using Cairo.

haskell-src-exts 0.4.1. Niklas Broberg announced a new major release of the haskell-src-exts package, an extension of the standard haskell-src package which handles most common syntactic extensions to Haskell. The new release features a cleaned up AST and names without ugly disambiguation prefixes.

darcs 2.1.1rc2. Eric Kow (kowey) announced the release of darcs 2.1.1rc2, which adds support for GHC 6.10.1. It also includes a Windows bug fix. If you're using GHC 6.10.1 or Windows, give it a try and let the darcs development team know how it works.

hpapi 0.1 release. Michael D. Adams announced the first release of hpapi, Performance API (PAPI) bindings for Haskell. PAPI provides access to various CPU counters such as cache-miss, instruction and pipeline stall counts.

Workflow-0.1. Alberto G. Corona announced the release of Workflow, a library for transparent execution of computations across shutdowns and restarts.

Reactive library (FRP) and mailing list. Conal Elliott announced the release of Reactive, a library for functional reactive programming (FRP), similar to the original Fran but with a more modern interface (using standard type classes) and a hybrid push/pull implementation. It is designed to be used in a variety of contexts, such as interactive 2D and 3D graphics, graphical user interfaces, web services, and automatic recompilation/re-execution. There is also now a mailing list and a feature/bug tracker.

ANN (sorta): OpenGL with extra type safety. Neal Alexander announced a modification of the hOpenGL (and GLFW) source tree to force extra type checking on its various IO actions using the -XGeneralizedNewtypeDeriving extension. The main motivation was for writing concurrent OpenGL applications; the second motivation was to enforce static type checking on commands that can only be executed in certain OpenGL contexts (sending vertex data for example). Hopefully the code will be uploaded to Hackage as a separate package soon.

FieldTrip library (functional 3D) and mailing list. Conal Elliott announced the release of FieldTrip, a library for functional 3D graphics. It is intended for building static, animated, and interactive 3D geometry, efficient enough for real-time synthesis and display. FieldTrip also has a mailing list and a feature/bug tracker.

gitit 0.2 release - wiki using HAppS, git, pandoc. John MacFarlane announced the upload of an early version of gitit, a Haskell wiki program, to HackageDB. Gitit uses HAppS as a webserver, git for file storage, pandoc for rendering the (markdown) pages, and highlighting-kate for highlighted source code. You can try it out here. Comments and patches welcome.

Discussion

Proof that Haskell is RT. Andrew Birkett asked whether there exists a formal proof that the Haskell language is referentially transparent. Such a thing cannot exist, since Haskell has no formally defined semantics, but an interesting discussion about referential transparency and semantics ensued anyway.

What *not* to use Haskell for. Dave Tapley asked how people answer the question, "what does Haskell not do well?" Unfortunately, it seems that there is no good answer to this question and the thread degenerated into a discussion of all the great things you can do with Haskell. If only Haskell sucked more.

Blog noise

Haskell news from the blogosphere.

Quotes of the Week

About the Haskell Weekly News

New editions are posted to the Haskell mailing list as well as to the Haskell Sequence and Planet Haskell. RSS is also available, and headlines appear on haskell.org.

To help create new editions of this newsletter, please see the information on how to contribute. Send stories to byorgey at cis dot upenn dot edu. The darcs repository is available at darcs get http://code.haskell.org/~byorgey/code/hwn/ .