I've tried to do cabal install readline on Snow Leopard with MacPorts and it fails with the infamous: $ cabal install readline ... checking for GNUreadline.framework... checking for readline... no checking for tputs in -lncurses... yes checking for readline in -lreadline... yes checking for rl_readline_version... yes checking for rl_begin_undo_group... no configure: error: readline not found, so this package cannot be built See `config.log' for more details. cabal: Error: some packages failed to install: readline-1.0.1.0 failed during the configure step. The exception was: exit: ExitFailure 1 Googilng shows the usual explanation that Mac'y broken clone interferes; yet I do have MacPorts and readline 6 there. So I try, per fixes recommended, $ cabal install readline --extra-include-dirs=/opt/local/include --extra-lib-dirs=/opt/local/lib ... checking for rl_readline_version... yes checking for rl_begin_undo_group... no ... -- same result. Downloaded the package and do configure manually: ./configure --with-readline-includes=/opt/local/include --with-readline-libraries=/opt/local/lib ... checking for readline in -lreadline... no checking for rl_readline_version... no ... Huh? $ port contents readline ... /opt/local/include/readline/readline.h ... /opt/local/lib/libreadline.5.0.dylib /opt/local/lib/libreadline.5.1.dylib /opt/local/lib/libreadline.5.2.dylib /opt/local/lib/libreadline.6.0.dylib /opt/local/lib/libreadline.6.dylib /opt/local/lib/libreadline.a /opt/local/lib/libreadline.dylib ... How should I properly tell cabal install readline where my readline is? Cheers, Alexy