1 files changed, 22 insertions, 0 deletions
diff --git a/src/Haddock/Parser/Util.hs b/src/Haddock/Parser/Util.hs
new file mode 100644
index 00000000..ea682601
--- /dev/null
+++ b/src/Haddock/Parser/Util.hs
@@ -0,0 +1,22 @@
+module Haddock.Parser.Util where
+
+import           Control.Applicative
+import           Control.Monad
+import           Data.Attoparsec.ByteString.Char8
+import           Data.ByteString.Char8 (ByteString)
+import qualified Data.ByteString.Char8 as BS
+
+takeUntil :: ByteString -> Parser ByteString
+takeUntil end_ = dropEnd <$> requireEnd (scan (False, end) p)
+  where
+    end = BS.unpack end_
+
+    p :: (Bool, String) -> Char -> Maybe (Bool, String)
+    p acc c = case acc of
+      (True, _) -> Just (False, end)
+      (_, []) -> Nothing
+      (_, x:xs) | x == c -> Just (False, xs)
+      _ -> Just (c == '\\', end)
+
+    dropEnd = BS.reverse . BS.drop (length end) . BS.reverse
+    requireEnd = mfilter (BS.isSuffixOf end_)