I'm sure this will be an easy question for those on this list. What do you need to add to a Cabal package description so as to allow an executable in the description to be built from the library it also describes? I searched the Cabal documentation many times, but came up empty handed. John $ make runhaskell Setup.hs build Preprocessing library a-1.0... Preprocessing executables for a-1.0... Building a-1.0... [1 of 1] Compiling A ( A.hs, dist/build/A.o ) /usr/bin/ar: creating dist/build/libHSa-1.0.a exec/Main.hs:3:7: Could not find module `A': Use -v to see a list of the files searched for. make: *** [all] Error 1 $ : after cleaning... $ more `find . -type f ` > ../a.txt $ cat ../a.txt :::::::::::::: ./a.cabal :::::::::::::: Name: a Version: 1.0 Build-Depends: base Exposed-Modules: A Executable: b Main-Is: Main.hs Other-Modules: A Hs-Source-Dirs: exec :::::::::::::: ./Setup.hs :::::::::::::: import Distribution.Simple main = defaultMain :::::::::::::: ./Makefile :::::::::::::: SETUP = runhaskell Setup.hs all: if test ! -f .setup-config; then $(SETUP) configure; fi $(SETUP) build Makefile: @echo make $@ %: force $(SETUP) $@ .PHONY: all force :::::::::::::: ./A.hs :::::::::::::: module A where a :: Int a = 3 :::::::::::::: ./exec/Main.hs :::::::::::::: module Main (main) where import A main :: IO () main = print a $ ghc -h ghc-6.6.1: unrecognised flags: -h Usage: For basic information, try the `--help' option. $ uname -a Linux goo 2.6.22.9-91.fc7 #1 SMP Thu Sep 27 23:10:59 EDT 2007 i686 i686 i386 GNU/Linux $