Installing Gtk2Hs on MacOS
After months of quiet yearning & frustration, I finally chewed into a big bullet and got Gtk2Hs installed on my Mac (OS 10.6.4 with GHC 6.12.3).
It was a long and harrowing affair. There were many confusing error messages. Ultimately, though, it was just a process of being patient with the various package managers and manually chasing down dependencies that are external to cabal. I had to use both Fink and MacPorts (and had to do lots of time-consuming update and selfupdate runs on these).
The Packages
Here are the packages I can remember having to install:
glib(from Fink)gtk+2(from Fink; NB-shliband-devpackages)- freetype (??)
- fontconfig (??)
cairo(from MacPorts)pango(from MacPorts)
After all that, cabal install gtk just worked. I was able to run example programs from this Gtk2Hs tutorial and get the windows to pop up and work correctly.
Double-Fisting
Running Fink and MacPorts is like having bacon on your sausage; it's a little redundant and includes much cholesterol, but it's easy to do and feels good at the time. Why I did this, or felt I had to, is now lost to me as well.
Misc. Stumbling Blocks
It bears noting that gtk and gtk+ are essentially synonyms, so don't go hunting for one when you've got the other. On the other hand, a "2" suffix there is essential: gtk2 and gtk-2.0 have nothing to do with "gtk" or "gtk 1.x"; they're essentially different products.
Several times I thought I was set having installed, say, the gtk+2 and gtk+2-shlibs packages from Fink, only to receive a complaint that gtk+2.pc (the pkg-config data file which other packages use to locate gtk+2) was missing, which made me gnash my teeth. The fix was to also install gtk+2-dev, which apparently should be called gtk+2-without-which-nothing.
Wordsize Conundra
I've had a number of minor 32- vs 64-bit problems with GHC. It seems that Haskell Platform installs a 32-bit ghc. (Why would this be? GHC does run 64-bit on MacOS, doesn't it?). Sometimes package managers install fat versions of libraries, which is good, but when using both Fink and MacPorts, a library with 64-bit-only versions might shadow the other.
Somewhere in the darkness, I had a problem with zlib being 64-bit and hence unusable, and I couldn't determine which library was using it in order to muck with it (it wasn't gtk itself, glib, nor the Haskell zlib bindings). This was fixed by un- and re-installing GHC via Haskell Platform, which entailed a minor version upgrade as well as perhaps clearing any strange customizations that I can't deny making to the 32-bitness of my GHC install.
(I'm surprised there's not a better system for managing such library flavors on OS X. Couldn't we keep separate system paths like /usr/local/lib64 and such? Or would this be a greater nightmare in itself?)
Apologies
I wish this were a more helpful document. If you try this soon, and hit a snag, let me know and I'll either remember how I resolved it, or try to add to what's here.