Implement simple string chunking based on HsColour library.

1 files changed, 27 insertions, 1 deletions

diff --git a/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs b/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs
index 4bcc0c8a..4e0d7382 100644
--- a/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs
+++ b/haddock-api/src/Haddock/Backends/Hyperlinker/Parser.hs
@@ -1,5 +1,8 @@
 module Haddock.Backends.Hyperlinker.Parser (parse) where
 
+import Data.Char
+import Data.List
+
 data Token = Token
     { tkType :: TokenType
     , tkValue :: String
@@ -27,7 +30,30 @@ parse :: String -> [Token]
 parse = tokenize . tag . chunk
 
 chunk :: String -> [String]
-chunk = undefined
+chunk [] = []
+chunk str@(c:_)
+    | isSpace c = chunk' $ span isSpace str
+chunk str
+    | "--" `isPrefixOf` str = chunk' $ span (not . (== '\n')) str
+    | "{-" `isPrefixOf` str = chunk' $ chunkComment 0 str
+    | otherwise = chunk' $ head $ lex str
+
+chunk' :: (String, String) -> [String]
+chunk' (c, rest) = c:(chunk rest)
+
+chunkComment :: Int -> String -> (String, String)
+chunkComment _ [] = ("", "")
+chunkComment depth ('{':'-':str) =
+    let (c, rest) = chunkComment (depth + 1) str
+    in ("{-" ++ c, rest)
+chunkComment depth ('-':'}':str)
+    | depth == 1 = ("-}", str)
+    | otherwise =
+        let (c, rest) = chunkComment (depth - 1) str
+        in ("-}" ++ c, rest)
+chunkComment depth (e:str) =
+    let (c, rest) = chunkComment depth str
+    in (e:c, rest)
 
 tag :: [String] -> [(Span, String)]
 tag =