4 files changed, 82 insertions, 32 deletions
diff --git a/src/compiler/GF.hs b/src/compiler/GF.hs
index cb63cadbe..bdb3e9b48 100644
--- a/src/compiler/GF.hs
+++ b/src/compiler/GF.hs
@@ -1,37 +1,36 @@
-module Main where
+module GF(
+           -- * Command line interface
+           module GF.Main,
+           module GF.Compiler,
+           module GF.Interactive,
 
+           -- * Compiling GF grammars
+           module GF.Compile,
+           module GF.CompileInParallel,
+           module GF.CompileOne,
+
+           -- * Abstract syntax, parsing and pretty printing
+           module GF.Compile.GetGrammar,
+           module GF.Grammar,
+
+           -- * Supporting infrastructure and system utilities
+           module GF.Data.Operations,
+           module GF.Infra.UseIO,
+           module GF.Infra.Option,
+           module GF.System.Console
+  ) where
+import GF.Main
 import GF.Compiler
 import GF.Interactive
-import GF.Data.ErrM
-import GF.Infra.Option
-import GF.Infra.UseIO
-import GF.Infra.BuildInfo (buildInfo)
-import Paths_gf
 
-import Data.Version
-import System.Directory
-import System.Environment (getArgs)
-import System.Exit
-import GF.System.Console (setConsoleEncoding)
+import GF.Compile
+import GF.CompileInParallel
+import GF.CompileOne
 
-main :: IO ()
-main = do
-  setConsoleEncoding
-  args <- getArgs
-  case parseOptions args of
-    Ok (opts,files) -> do curr_dir <- getCurrentDirectory
-                          lib_dir  <- getLibraryDirectory opts
-                          mainOpts (fixRelativeLibPaths curr_dir lib_dir opts) files
-    Bad err         -> do ePutStrLn err
-                          ePutStrLn "You may want to try --help."
-                          exitFailure
+import GF.Compile.GetGrammar
+import GF.Grammar
 
-mainOpts :: Options -> [FilePath] -> IO ()
-mainOpts opts files = 
-    case flag optMode opts of
-      ModeVersion     -> putStrLn $ "Grammatical Framework (GF) version " ++ showVersion version ++ "\n" ++ buildInfo
-      ModeHelp        -> putStrLn helpMessage
-      ModeInteractive -> mainGFI opts files
-      ModeRun         -> mainRunGFI opts files
-      ModeServer port -> mainServerGFI opts port files
-      ModeCompiler    -> mainGFC opts files
+import GF.Data.Operations
+import GF.Infra.Option
+import GF.Infra.UseIO
+import GF.System.Console
diff --git a/src/compiler/GF/Infra/UseIO.hs b/src/compiler/GF/Infra/UseIO.hs
index e0477c1fc..58010f7f9 100644
--- a/src/compiler/GF/Infra/UseIO.hs
+++ b/src/compiler/GF/Infra/UseIO.hs
@@ -12,7 +12,7 @@
 -- (Description of the module)
 -----------------------------------------------------------------------------
 
-module GF.Infra.UseIO(module GF.Infra.UseIO,liftErr,
+module GF.Infra.UseIO(module GF.Infra.UseIO,
                       -- ** Reused
                       MonadIO(..),liftErr) where
 
diff --git a/src/compiler/GF/Main.hs b/src/compiler/GF/Main.hs
new file mode 100644
index 000000000..c7656248f
--- /dev/null
+++ b/src/compiler/GF/Main.hs
@@ -0,0 +1,48 @@
+-- | GF main program (grammar compiler, interactive shell, http server)
+module GF.Main where
+import GF.Compiler
+import GF.Interactive
+import GF.Data.ErrM
+import GF.Infra.Option
+import GF.Infra.UseIO
+import GF.Infra.BuildInfo (buildInfo)
+import Paths_gf
+
+import Data.Version
+import System.Directory
+import System.Environment (getArgs)
+import System.Exit
+import GF.System.Console (setConsoleEncoding)
+
+-- | Run the GF main program, taking arguments from the command line.
+-- (It calls 'setConsoleEncoding' and 'getOptions', then 'mainOpts'.)
+-- Run @gf --help@ for usage info.
+main :: IO ()
+main = do
+  setConsoleEncoding
+  uncurry mainOpts =<< getOptions
+
+-- | Get and parse GF command line arguments. Fix relative paths.
+getOptions = do
+  args <- getArgs
+  case parseOptions args of
+    Ok (opts,files) -> do curr_dir <- getCurrentDirectory
+                          lib_dir  <- getLibraryDirectory opts
+                          return (fixRelativeLibPaths curr_dir lib_dir opts, files)
+    Bad err         -> do ePutStrLn err
+                          ePutStrLn "You may want to try --help."
+                          exitFailure
+
+
+-- | Run the GF main program with the given options and files. Depending on
+-- the options it invokes 'mainGFC', 'mainGFI', 'mainRunGFI', 'mainServerGFI',
+-- or it just prints version/usage info.
+mainOpts :: Options -> [FilePath] -> IO ()
+mainOpts opts files = 
+    case flag optMode opts of
+      ModeVersion     -> putStrLn $ "Grammatical Framework (GF) version " ++ showVersion version ++ "\n" ++ buildInfo
+      ModeHelp        -> putStrLn helpMessage
+      ModeInteractive -> mainGFI opts files
+      ModeRun         -> mainRunGFI opts files
+      ModeServer port -> mainServerGFI opts port files
+      ModeCompiler    -> mainGFC opts files
diff --git a/src/programs/gf.hs b/src/programs/gf.hs
new file mode 100644
index 000000000..1dae54bc7
--- /dev/null
+++ b/src/programs/gf.hs
@@ -0,0 +1,3 @@
+import qualified GF
+
+main = GF.main