I believe I have wxWidgets installed, because when I go to the demos/ or samples/ subfolders of ~/wxWidgets-3.0.2/build-cocoa-debug/, I can run the apps. Now I want to install the phooey library for Haskell. When I try, I am warned that some things will be broken, so I unregister them and then cabal install them all at once. (The complete output from my session with cabal appears below.) I run cabal from ~/wxWidgets, because that folder contains the files wx-config-inplace.in wx-config.in and I know cabal wants wx-config. The two errors I get: wx-config is not found checkers does not install I am left stumped. Thanks for your help. -------------------- jefferys-mbp:~ jbb$ cd wxWidgets-3.0.2/ jefferys-mbp:wxWidgets-3.0.2 jbb$ cabal install phooey Resolving dependencies... In order, the following would be installed: mtl-1.1.1.1 (latest: 2.2.1) (new version) parsec-3.1.7 (reinstall) changes: mtl-2.2.1 -> 1.1.1.1 reactive-0.5.0.1 (latest: 0.11.5) (new package) wxdirect-0.91.0.0 (reinstall) wxc-0.91.0.0 (new package) wxcore-0.91.0.0 (new package) wx-0.91.0.0 (new package) phooey-2.0.0.1 (new package) cabal: The following packages are likely to be broken by the reinstalls: tidal-0.4.21 network-uri-2.6.0.1 threepenny-gui-0.5.0.0 hmt-0.15 Use --force-reinstalls if you want to install anyway. jefferys-mbp:wxWidgets-3.0.2 jbb$ ghc-pkg unregister tidal jefferys-mbp:wxWidgets-3.0.2 jbb$ ghc-pkg unregister threepenny-gui jefferys-mbp:wxWidgets-3.0.2 jbb$ ghc-pkg unregister network-uri jefferys-mbp:wxWidgets-3.0.2 jbb$ ghc-pkg unregister hmt jefferys-mbp:wxWidgets-3.0.2 jbb$ cabal install tidal network-uri threepenny-gui hmt phooey Resolving dependencies... Configuring checkers-0.1.4... Configuring network-uri-2.6.0.1... Configuring hmt-0.15... Configuring wxc-0.91.0.0... Building network-uri-2.6.0.1... Building checkers-0.1.4... Building hmt-0.15... Failed to install checkers-0.1.4 Last 10 lines of the build log ( /Users/jbb/.cabal/logs/checkers-0.1.4.log ): at src/Test/QuickCheck/Instances/Num.hs:23:12-49 Possible fix: add (Eq a) to the context of the type signature for nonZero :: (Num a, Arbitrary a) => Gen a -> Gen a In the first argument of ‘satisfiesM’, namely ‘(/= 0)’ In the expression: satisfiesM (/= 0) (if (s == 0) then (resize 1 g) else g) In the first argument of ‘sized’, namely ‘(\ s -> satisfiesM (/= 0) (if (s == 0) then (resize 1 g) else g))’ Failed to install wxc-0.91.0.0 Last 10 lines of the build log ( /Users/jbb/.cabal/logs/wxc-0.91.0.0.log ): [1 of 1] Compiling Main ( /var/folders/q1/2_cf13z53tg__sqdk7v8ycgm0000gn/T/wxc-0.91.0.0-41510/wxc-0.91.0.0/Setup.hs, /var/folders/q1/2_cf13z53tg__sqdk7v8ycgm0000gn/T/wxc-0.91.0.0-41510/wxc-0.91.0.0/dist/setup/Main.o ) Linking /var/folders/q1/2_cf13z53tg__sqdk7v8ycgm0000gn/T/wxc-0.91.0.0-41510/wxc-0.91.0.0/dist/setup/setup ... Error: wx-config not found, please install wx-config before installing wxc Installed network-uri-2.6.0.1 Configuring threepenny-gui-0.5.0.0... Building threepenny-gui-0.5.0.0... Installed threepenny-gui-0.5.0.0 Installed hmt-0.15 Configuring tidal-0.4.21... Building tidal-0.4.21... Installed tidal-0.4.21 Updating documentation index /Users/jbb/Library/Haskell/share/doc/index.html cabal: Error: some packages failed to install: checkers-0.1.4 failed during the building phase. The exception was: ExitFailure 1 phooey-2.0 depends on wxc-0.91.0.0 which failed to install. reactive-0.9.3 depends on checkers-0.1.4 which failed to install. wx-0.91.0.0 depends on wxc-0.91.0.0 which failed to install. wxc-0.91.0.0 failed during the configure step. The exception was: ExitFailure 1 wxcore-0.91.0.0 depends on wxc-0.91.0.0 which failed to install.