git.iko.soy/elk
on 1ed37fe help sign in
elk/compiler/SourceSyntax/Location.hs
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1{-# LANGUAGE DeriveDataTypeable #-}
2module SourceSyntax.Location where
4import Data.Data
5import Text.PrettyPrint
6import SourceSyntax.PrettyPrint
7import qualified Text.Parsec.Pos as Parsec
9data SrcPos = Pos { line :: Int, column :: Int }
10 deriving (Eq, Ord, Data, Typeable)
12data SrcSpan = Span SrcPos SrcPos String | NoSpan String
13 deriving (Eq, Ord, Data, Typeable)
15data Located e = L SrcSpan e
16 deriving (Eq, Ord, Data, Typeable)
18none e = L (NoSpan (render $ pretty e)) e
19noneNoDocs = L (NoSpan "")
21at start end e = L (Span (Pos (Parsec.sourceLine start) (Parsec.sourceColumn start))
22 (Pos (Parsec.sourceLine end ) (Parsec.sourceColumn end ))
23 (render $ pretty e)) e
25merge (L s1 _) (L s2 _) e = L (span (render $ pretty e)) e
26 where span = case (s1,s2) of
27 (Span start _ _, Span _ end _) -> Span start end
28 (Span start end _, _) -> Span start end
29 (_, Span start end _) -> Span start end
30 (_, _) -> NoSpan
32mergeOldDocs (L s1 _) (L s2 _) e = L span e
33 where span = case (s1,s2) of
34 (Span start _ d1, Span _ end d2) -> Span start end (d1 ++ "\n\n" ++ d2)
35 (Span _ _ _, _) -> s1
36 (_, Span _ _ _) -> s2
37 (_, _) -> NoSpan ""
39sameAs (L s _) = L s
42instance Show SrcPos where
43 show (Pos r c) = show r ++ "," ++ show c
45instance Show SrcSpan where
46 show span =
47 case span of
48 NoSpan _ -> ""
49 Span start end _ ->
50 case line start == line end of
51 False -> "between lines " ++ show (line start) ++ " and " ++ show (line end)
52 True -> "on line " ++ show (line end) ++ ", column " ++
53 show (column start) ++ " to " ++ show (column end)
55instance Show e => Show (Located e) where
56 show (L s e) = "L (" ++ show s ++ ") (" ++ show e ++ ")"
58instance Pretty a => Pretty (Located a) where
59 pretty (L _ e) = pretty e