X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fmain%2FGHC.hs;h=a5d82b86e0f392fe89b72ccd929f7e400d630710;hb=ee2623c8841a3a26c37bd7695a7db7be5d7e3a7f;hp=5e9aab705f0fa6b34500ba93c1051629b076d307;hpb=3eb04da9d3534cc379d1459ec2991e63a03dd377;p=ghc-hetmet.git

diff --git a/compiler/main/GHC.hs b/compiler/main/GHC.hs
index 5e9aab7..a5d82b8 100644
--- a/compiler/main/GHC.hs
+++ b/compiler/main/GHC.hs
@@ -18,6 +18,7 @@ module GHC (
         clearWarnings, getWarnings, hasWarnings,
         printExceptionAndWarnings, printWarnings,
         handleSourceError, defaultCallbacks, GhcApiCallbacks(..),
+        needsTemplateHaskell,
 
 	-- * Flags and settings
 	DynFlags(..), DynFlag(..), Severity(..), HscTarget(..), dopt,
@@ -1119,7 +1120,13 @@ desugarModule tcm = do
 
 -- | Load a module.  Input doesn't need to be desugared.
 --
--- XXX: Describe usage.
+-- A module must be loaded before dependent modules can be typechecked.  This
+-- always includes generating a 'ModIface' and, depending on the
+-- 'DynFlags.hscTarget', may also include code generation.
+--
+-- This function will always cause recompilation and will always overwrite
+-- previous compilation results (potentially files on disk).
+--
 loadModule :: (TypecheckedMod mod, GhcMonad m) => mod -> m mod
 loadModule tcm = do
    let ms = modSummary tcm
@@ -2349,6 +2356,15 @@ workingDirectoryChanged = withSession $ (liftIO . flushFinderCaches)
 getModuleGraph :: GhcMonad m => m ModuleGraph -- ToDo: DiGraph ModSummary
 getModuleGraph = liftM hsc_mod_graph getSession
 
+-- | Determines whether a set of modules requires Template Haskell.
+--
+-- Note that if the session's 'DynFlags' enabled Template Haskell when
+-- 'depanal' was called, then each module in the returned module graph will
+-- have Template Haskell enabled whether it is actually needed or not.
+needsTemplateHaskell :: ModuleGraph -> Bool
+needsTemplateHaskell ms =
+    any (dopt Opt_TemplateHaskell . ms_hspp_opts) ms
+
 -- | Return @True@ <==> module is loaded.
 isLoaded :: GhcMonad m => ModuleName -> m Bool
 isLoaded m = withSession $ \hsc_env ->