The way to do this is, of course, to compile and run this program (in a file `Main.hs'):
main = putStr "Hello, world!\n"
First, give yourself a convenient way to execute the driver script `ghc/driver/ghc', perhaps something like...
% ln -s /local/src/ghc-x.xx/ghc/driver/ghc ~/bin/alpha/ghc % rehash
Compile the program, using the `-v' (verbose) flag to verify that libraries, etc., are being found properly:
% ghc -v -o hello Main.hs
Now run it:
% ./hello Hello, world!
Some simple-but-profitable tests are to compile and run the notorious `nfib' program, using different numeric types. Start with `nfib :: Int -> Int', and then try `Integer', `Float', `Double', `Rational' and maybe `Complex Float'. Code for this is distributed in `ghc/misc/examples/nfib/'.
For more information on how to "drive" GHC, either do `ghc -help' or consult the User's Guide (distributed in `ghc/docs/users_guide').