unused import

[ghc-hetmet.git] / compiler / ghci / InteractiveUI.hs

diff --git a/compiler/ghci/InteractiveUI.hs b/compiler/ghci/InteractiveUI.hs
index a1aaa6a..3f7a0f5 100644 (file)
--- a/compiler/ghci/InteractiveUI.hs
+++ b/compiler/ghci/InteractiveUI.hs
@@ -79,7 +79,7 @@ import Control.Monad as Monad
 
 import Foreign.StablePtr       ( newStablePtr )
 import GHC.Exts                ( unsafeCoerce# )
-import GHC.IOBase      ( IOErrorType(InvalidArgument), IO(IO) )
+import GHC.IOBase      ( IOErrorType(InvalidArgument) )
 
 import Data.IORef      ( IORef, readIORef, writeIORef )
 
@@ -1200,7 +1200,8 @@ showCmd str =
        ["bindings"] -> showBindings
        ["linker"]   -> io showLinkerState
         ["breaks"] -> showBkptTable
-       _ -> throwDyn (CmdLineError "syntax:  :show [modules|bindings]")
+        ["context"] -> showContext
+       _ -> throwDyn (CmdLineError "syntax:  :show [modules|bindings|breaks]")
 
 showModules = do
   session <- getSession
@@ -1234,6 +1235,13 @@ showBkptTable = do
    activeBreaks <- getActiveBreakPoints 
    printForUser $ ppr activeBreaks 
 
+showContext :: GHCi ()
+showContext = do
+   st <- getGHCiState
+   printForUser $ vcat (map pp_resume (resume st))
+  where
+   pp_resume (span, _, _) = ptext SLIT("Stopped at") <+> ppr span
+
 -- -----------------------------------------------------------------------------
 -- Completion
 
@@ -1573,10 +1581,12 @@ findBreakAndSet mod lookupTickTree = do
 --    - the rightmost subexpression enclosing the specified line
 --
 findBreakByLine :: Int -> TickArray -> Maybe (BreakIndex,SrcSpan)
-findBreakByLine line arr = 
-  listToMaybe (sortBy leftmost complete)   `mplus`
-  listToMaybe (sortBy leftmost incomplete) `mplus`
-  listToMaybe (sortBy rightmost ticks)
+findBreakByLine line arr
+  | not (inRange (bounds arr) line) = Nothing
+  | otherwise =
+    listToMaybe (sortBy leftmost complete)   `mplus`
+    listToMaybe (sortBy leftmost incomplete) `mplus`
+    listToMaybe (sortBy rightmost ticks)
   where 
         ticks = arr ! line
 
@@ -1587,8 +1597,10 @@ findBreakByLine line arr =
             where ends_here (nm,span) = srcSpanEndLine span == line
 
 findBreakByCoord :: (Int,Int) -> TickArray -> Maybe (BreakIndex,SrcSpan)
-findBreakByCoord (line, col) arr =
-  listToMaybe (sortBy rightmost contains)
+findBreakByCoord (line, col) arr
+  | not (inRange (bounds arr) line) = Nothing
+  | otherwise =
+    listToMaybe (sortBy rightmost contains)
   where 
         ticks = arr ! line