-- ** Constructing Located
noLoc,
- mkGeneralLocated,
+ mkGeneralLocated,
-- ** Deconstructing Located
getLoc, unLoc,
spans, isSubspanOf
) where
+#include "Typeable.h"
+
import Util
import Outputable
import FastString
+
+import Data.Bits
+import Data.Data
\end{code}
%************************************************************************
data SrcLoc
= SrcLoc FastString -- A precise location (file name)
{-# UNPACK #-} !Int -- line number, begins at 1
- {-# UNPACK #-} !Int -- column number, begins at 0
- -- Don't ask me why lines start at 1 and columns start at
- -- zero. That's just the way it is, so there. --SDM
-
+ {-# UNPACK #-} !Int -- column number, begins at 1
| UnhelpfulLoc FastString -- Just a general indication
\end{code}
-- | 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) 0
+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
+advanceSrcLoc loc _ = loc -- Better than nothing
\end{code}
%************************************************************************
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)
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}
%************************************************************************
-- 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
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}
%************************************************************************
isGoodSrcSpan _ = False
isOneLineSpan :: SrcSpan -> Bool
--- ^ True if the span is known to straddle more than one line.
+-- ^ True if the span is known to straddle only one line.
-- For "bad" 'SrcSpan', it returns False
isOneLineSpan s
| isGoodSrcSpan s = srcSpanStartLine s == srcSpanEndLine s
ppr span
= getPprStyle $ \ sty ->
if userStyle sty || debugStyle sty then
- pprUserSpan span
+ pprUserSpan True span
else
hcat [text "{-# LINE ", int (srcSpanStartLine span), space,
char '\"', pprFastFilePath $ srcSpanFile span, text " #-}"]
-pprUserSpan :: SrcSpan -> SDoc
-pprUserSpan (SrcSpanOneLine src_path line start_col end_col)
- = hcat [ pprFastFilePath src_path, char ':',
- int line,
- char ':', int start_col
- ]
- <> if end_col - start_col <= 1
- then empty
- -- for single-character or point spans, we just output the starting
- -- column number
- else char '-' <> int (end_col-1)
-
-pprUserSpan (SrcSpanMultiLine src_path sline scol eline ecol)
- = hcat [ pprFastFilePath src_path, char ':',
- parens (int sline <> char ',' <> int scol),
- char '-',
- parens (int eline <> char ',' <>
- if ecol == 0 then int ecol else int (ecol-1))
- ]
-
-pprUserSpan (SrcSpanPoint src_path line col)
- = hcat [ pprFastFilePath src_path, char ':',
- int line,
- char ':', int col
+pprUserSpan :: Bool -> SrcSpan -> SDoc
+pprUserSpan show_path (SrcSpanOneLine src_path line start_col end_col)
+ = hcat [ ppWhen show_path (pprFastFilePath src_path <> colon)
+ , int line, char ':', int start_col
+ , ppUnless (end_col - start_col <= 1)
+ (char '-' <> int (end_col-1))
+ -- For single-character or point spans, we just
+ -- output the starting column number
+ ]
+
+
+pprUserSpan show_path (SrcSpanMultiLine src_path sline scol eline ecol)
+ = hcat [ ppWhen show_path (pprFastFilePath src_path <> colon)
+ , parens (int sline <> char ',' <> int scol)
+ , char '-'
+ , parens (int eline <> char ',' <>
+ if ecol == 0 then int ecol else int (ecol-1))
]
-pprUserSpan (UnhelpfulSpan s) = ftext s
+pprUserSpan show_path (SrcSpanPoint src_path line col)
+ = hcat [ ppWhen show_path $ (pprFastFilePath src_path <> colon)
+ , int line, char ':', int col ]
+
+pprUserSpan _ (UnhelpfulSpan s) = ftext s
pprDefnLoc :: SrcSpan -> SDoc
-- ^ Pretty prints information about the 'SrcSpan' in the style "defined at ..."
\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
fmap f (L l e) = L l (f e)
instance Outputable e => Outputable (Located e) where
- ppr (L _ e) = ppr e
- -- do we want to dump the span in debugSty mode?
+ ppr (L l e) = ifPprDebug (braces (pprUserSpan False l)) $$ ppr e
+ -- Print spans without the file name etc
\end{code}
%************************************************************************