Improve targetContents code docs

3 files changed, 9 insertions, 6 deletions

diff --git a/compiler/main/DriverPipeline.hs b/compiler/main/DriverPipeline.hs
index 78e4a810d7..d2814b71f2 100644
--- a/compiler/main/DriverPipeline.hs
+++ b/compiler/main/DriverPipeline.hs
@@ -51,7 +51,7 @@ import ErrUtils
 import DynFlags
 import Panic
 import Util
-import StringBuffer     ( StringBuffer, hGetStringBuffer, hPutStringBuffer )
+import StringBuffer     ( hGetStringBuffer, hPutStringBuffer )
 import BasicTypes       ( SuccessFlag(..) )
 import Maybes           ( expectJust )
 import SrcLoc
@@ -90,8 +90,8 @@ import Data.Time        ( UTCTime )
 
 preprocess :: HscEnv
            -> FilePath -- ^ input filename
-           -> Maybe StringBuffer
-           -- ^ optional buffer to use instead of reading input file
+           -> Maybe InputFileBuffer
+           -- ^ optional buffer to use instead of reading the input file
            -> Maybe Phase -- ^ starting phase
            -> IO (Either ErrorMessages (DynFlags, FilePath))
 preprocess hsc_env input_fn mb_input_buf mb_phase =
@@ -579,7 +579,7 @@ doLink dflags stop_phase o_files
 runPipeline
   :: Phase                      -- ^ When to stop
   -> HscEnv                     -- ^ Compilation environment
-  -> (FilePath, Maybe StringBuffer, Maybe PhasePlus)
+  -> (FilePath, Maybe InputFileBuffer, Maybe PhasePlus)
                                 -- ^ Pipeline input file name, optional
                                 -- buffer and maybe -x suffix
   -> Maybe FilePath             -- ^ original basename (if different from ^^^)
diff --git a/compiler/main/GhcMake.hs b/compiler/main/GhcMake.hs
index c0048c6075..a748cc668b 100644
--- a/compiler/main/GhcMake.hs
+++ b/compiler/main/GhcMake.hs
@@ -2529,6 +2529,7 @@ getPreprocessedImports
     -> FilePath
     -> Maybe Phase
     -> Maybe (StringBuffer, UTCTime)
+    -- ^ optional source code buffer and modification time
     -> ExceptT ErrorMessages IO PreprocessedImports
 getPreprocessedImports hsc_env src_fn mb_phase maybe_buf = do
   (pi_local_dflags, pi_hspp_fn)
diff --git a/compiler/main/HscTypes.hs b/compiler/main/HscTypes.hs
index e75b2457f0..dba39c97f0 100644
--- a/compiler/main/HscTypes.hs
+++ b/compiler/main/HscTypes.hs
@@ -13,7 +13,7 @@ module HscTypes (
         -- * compilation state
         HscEnv(..), hscEPS,
         FinderCache, FindResult(..), InstalledFindResult(..),
-        Target(..), TargetId(..), pprTarget, pprTargetId,
+        Target(..), TargetId(..), InputFileBuffer, pprTarget, pprTargetId,
         HscStatus(..),
         IServ(..),
 
@@ -511,7 +511,7 @@ data Target
   = Target {
       targetId           :: TargetId, -- ^ module or filename
       targetAllowObjCode :: Bool,     -- ^ object code allowed?
-      targetContents     :: Maybe (StringBuffer,UTCTime)
+      targetContents     :: Maybe (InputFileBuffer, UTCTime)
       -- ^ Optional in-memory buffer containing the source code GHC should
       -- use for this target instead of reading it from disk.
       --
@@ -534,6 +534,8 @@ data TargetId
         -- should be determined from the suffix of the filename.
   deriving Eq
 
+type InputFileBuffer = StringBuffer
+
 pprTarget :: Target -> SDoc
 pprTarget (Target id obj _) =
     (if obj then char '*' else empty) <> pprTargetId id