X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FbasicTypes%2FSrcLoc.lhs;h=d2cbd7f07c2cb987ec17ae17d52d65e6def6c65e;hp=20e1bca9c32b84d6c95a011f6e01452dd9cc27ba;hb=0af06ed99ed56341adfdda4a92a0a36678780109;hpb=8371c6389ea42280eb202acd16bf33e4fc036555

diff --git a/compiler/basicTypes/SrcLoc.lhs b/compiler/basicTypes/SrcLoc.lhs
index 20e1bca..d2cbd7f 100644
--- a/compiler/basicTypes/SrcLoc.lhs
+++ b/compiler/basicTypes/SrcLoc.lhs
@@ -69,9 +69,14 @@ module SrcLoc (
         spans, isSubspanOf
     ) where
 
+#include "Typeable.h"
+
 import Util
 import Outputable
 import FastString
+
+import Data.Bits
+import Data.Data
 \end{code}
 
 %************************************************************************
@@ -124,17 +129,20 @@ srcLocFile _other	      = (fsLit "<unknown file")
 -- | Raises an error when used on a "bad" 'SrcLoc'
 srcLocLine :: SrcLoc -> Int
 srcLocLine (SrcLoc _ l _) = l
-srcLocLine _other	  = panic "srcLocLine: unknown line"
+srcLocLine (UnhelpfulLoc s) = pprPanic "srcLocLine" (ftext s)
 
 -- | Raises an error when used on a "bad" 'SrcLoc'
 srcLocCol :: SrcLoc -> Int
 srcLocCol (SrcLoc _ _ c) = c
-srcLocCol _other         = panic "srcLocCol: unknown col"
+srcLocCol (UnhelpfulLoc s) = pprPanic "srcLocCol" (ftext s)
 
--- | Move the 'SrcLoc' down by one line if the character is a newline
--- and across by one character in any other case
+-- | Move the 'SrcLoc' down by one line if the character is a newline,
+-- to the next 8-char tabstop if it is a tab, and across by one
+-- character in any other case
 advanceSrcLoc :: SrcLoc -> Char -> SrcLoc
 advanceSrcLoc (SrcLoc f l _) '\n' = SrcLoc f  (l + 1) 1
+advanceSrcLoc (SrcLoc f l c) '\t' = SrcLoc f  l (((((c - 1) `shiftR` 3) + 1)
+                                                  `shiftL` 3) + 1)
 advanceSrcLoc (SrcLoc f l c) _    = SrcLoc f  l (c + 1)
 advanceSrcLoc loc            _    = loc -- Better than nothing
 \end{code}
@@ -157,11 +165,11 @@ instance Ord SrcLoc where
    
 cmpSrcLoc :: SrcLoc -> SrcLoc -> Ordering
 cmpSrcLoc (UnhelpfulLoc s1) (UnhelpfulLoc s2) = s1 `compare` s2
-cmpSrcLoc (UnhelpfulLoc _)  _other            = LT
+cmpSrcLoc (UnhelpfulLoc _)  (SrcLoc _ _ _)    = GT
+cmpSrcLoc (SrcLoc _ _ _)    (UnhelpfulLoc _)  = LT
 
 cmpSrcLoc (SrcLoc s1 l1 c1) (SrcLoc s2 l2 c2)      
   = (s1 `compare` s2) `thenCmp` (l1 `compare` l2) `thenCmp` (c1 `compare` c2)
-cmpSrcLoc (SrcLoc _ _ _) _other = GT
 
 instance Outputable SrcLoc where
     ppr (SrcLoc src_path src_line src_col)
@@ -176,6 +184,12 @@ instance Outputable SrcLoc where
                   char '\"', pprFastFilePath src_path, text " #-}"]
 
     ppr (UnhelpfulLoc s)  = ftext s
+
+instance Data SrcSpan where
+  -- don't traverse?
+  toConstr _   = abstractConstr "SrcSpan"
+  gunfold _ _  = error "gunfold"
+  dataTypeOf _ = mkNoRepType "SrcSpan"
 \end{code}
 
 %************************************************************************
@@ -221,10 +235,10 @@ data SrcSpan
 				-- also used to indicate an empty span
 
 #ifdef DEBUG
-  deriving (Eq, Show)	-- Show is used by Lexer.x, becuase we
-			-- derive Show for Token
+  deriving (Eq, Typeable, Show) -- Show is used by Lexer.x, becuase we
+                                -- derive Show for Token
 #else
-  deriving Eq
+  deriving (Eq, Typeable)
 #endif
 
 -- | Built-in "bad" 'SrcSpan's for common sources of location uncertainty
@@ -262,20 +276,18 @@ mkSrcSpan loc1 loc2
 combineSrcSpans	:: SrcSpan -> SrcSpan -> SrcSpan
 combineSrcSpans	(UnhelpfulSpan _) r = r -- this seems more useful
 combineSrcSpans	l (UnhelpfulSpan _) = l
-combineSrcSpans	start end 
- = case line1 `compare` line2 of
-     EQ -> case col1 `compare` col2 of
-		EQ -> SrcSpanPoint file line1 col1
-		LT -> SrcSpanOneLine file line1 col1 col2
-		GT -> SrcSpanOneLine file line1 col2 col1
-     LT -> SrcSpanMultiLine file line1 col1 line2 col2
-     GT -> SrcSpanMultiLine file line2 col2 line1 col1
+combineSrcSpans	span1 span2
+ = if line_start == line_end 
+   then if col_start == col_end
+        then SrcSpanPoint     file line_start col_start
+        else SrcSpanOneLine   file line_start col_start col_end
+   else      SrcSpanMultiLine file line_start col_start line_end col_end
   where
-	line1 = srcSpanStartLine start
-	col1  = srcSpanStartCol start
-	line2 = srcSpanEndLine end
-	col2  = srcSpanEndCol end
-	file  = srcSpanFile start
+    (line_start, col_start) = min (srcSpanStartLine span1, srcSpanStartCol span1)
+    		 	          (srcSpanStartLine span2, srcSpanStartCol span2)
+    (line_end, col_end)     = max (srcSpanEndLine span1, srcSpanEndCol span1)
+    		  	          (srcSpanEndLine span2, srcSpanEndCol span2)
+    file = srcSpanFile span1
 \end{code}
 
 %************************************************************************
@@ -438,6 +450,7 @@ pprDefnLoc loc
 \begin{code}
 -- | We attach SrcSpans to lots of things, so let's have a datatype for it.
 data Located e = L SrcSpan e
+  deriving (Eq, Ord, Typeable, Data)
 
 unLoc :: Located e -> e
 unLoc (L _ e) = e
@@ -474,7 +487,7 @@ instance Functor Located where
   fmap f (L l e) = L l (f e)
 
 instance Outputable e => Outputable (Located e) where
-  ppr (L l e) = ifPprDebug (braces (pprUserSpan False l)) <> ppr e
+  ppr (L l e) = ifPprDebug (braces (pprUserSpan False l)) $$ ppr e
 		-- Print spans without the file name etc
 \end{code}