-- 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 `shiftR` 3) + 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