compiler/SourceSyntax/Location.hs · elk

on 06503fe help sign in

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1module SourceSyntax.Location where

3import Text.PrettyPrint

4import SourceSyntax.PrettyPrint

5import qualified Text.Parsec.Pos as Parsec

7data SrcPos = Pos { line :: Int, column :: Int }

8 deriving (Eq, Ord)

10data SrcSpan = Span SrcPos SrcPos String | NoSpan String

11 deriving (Eq, Ord)

13data Located e = L SrcSpan e

14 deriving (Eq, Ord)

16none e = L (NoSpan (render $ pretty e)) e

17noneNoDocs = L (NoSpan "")

19at start end e = L (Span (Pos (Parsec.sourceLine start) (Parsec.sourceColumn start))

20 (Pos (Parsec.sourceLine end ) (Parsec.sourceColumn end ))

21 (render $ pretty e)) e

23merge (L s1 _) (L s2 _) e = L (span (render $ pretty e)) e

24 where span = case (s1,s2) of

25 (Span start _ _, Span _ end _) -> Span start end

26 (Span start end _, _) -> Span start end

27 (_, Span start end _) -> Span start end

28 (_, _) -> NoSpan

30mergeOldDocs (L s1 _) (L s2 _) e = L span e

31 where span = case (s1,s2) of

32 (Span start _ d1, Span _ end d2) -> Span start end (d1 ++ "\n\n" ++ d2)

33 (Span _ _ _, _) -> s1

34 (_, Span _ _ _) -> s2

35 (_, _) -> NoSpan ""

37sameAs (L s _) = L s

40instance Show SrcPos where

41 show (Pos r c) = show r ++ "," ++ show c

43instance Show SrcSpan where

44 show span =

45 case span of

46 NoSpan _ -> ""

47 Span start end _ ->

48 case line start == line end of

49 False -> "between lines " ++ show (line start) ++ " and " ++ show (line end)

50 True -> "on line " ++ show (line end) ++ ", column " ++

51 show (column start) ++ " to " ++ show (column end)

53instance Show e => Show (Located e) where

54 show (L _ e) = show e

56instance Pretty a => Pretty (Located a) where

57 pretty (L _ e) = pretty e