Update: these instructions refer to the HAppS, 0.8.8. The latest version (September 2007) if 0.9.1a. It radically alters the HAppS APIs as well as the installation procedure. You can find more information here which is an incomplete tutorial inside one of the new source code repositories.
Get the latest version of ghc for your platform:
Get the latest version of darcs:
Throughout, when building HAppS or any of it’s dependencies use:
$ runhaskell Setup.hs configure $ runhaskell Setup.hs build $ sudo runhaskell Setup.hs install
and not the makefiles. Even where the README or web page says otherwise. In some instances Setup.lhs will be provided instead of Setup.hs.
Use the latest source for HAppS 0.8.8 not the stable version. The stable version won’t build! Get it via darcs not tarballs. The tarballs are broken links!
darcs get --partial http://happs.org/HAppS
Try and build HAppS (with the commands in step 3 above), and every time you fail, install the missing packages. The documentation in the HAppS tutorial is up-to-date (as of September 2007) on this score. So you may be better off there than here if it is long after that date.
The hackage package list is useful but not complete.
HList is a special case as it doesn’t have a conveniently downloadable package. Use:
wget -r -nH -X '*/_darcs' -np http://darcs.haskell.org/HList/
Plus the following are only available via darcs: syb-with-class ( darcs get http://happs.org/HAppS/syb-with-class ), default ( darcs get http://happs.org/HAppS/default ), normalize ( darcs get http://happs.org/HAppS/normalize ), generic-xml ( darcs get http://happs.org/HAppS/generic-xml )
You can test your installation with the “Hello World” in the HAppS Tutorial
Update: the rest of the HAppS tutorial was fairly dense and difficult to understand as well as being somewhat out of date. To remedy this situation I wrote Simple Haskell Web Programming with HAppS.