example.hs

data Category = Category { catName :: String
                         , leaderboard :: Url} deriving (Show)
instance FromJSON Category where
    parseJSON (Object o) = Category
        <$> (o .: "name")
        <*> (last <$> o .: "links" >>= (.: "uri"))

data RunData = RunData { runs :: [Run]} deriving (Show)
instance FromJSON RunData where
    parseJSON (Object o) = RunData
        <$> ((o .: "data") >>= (.: "runs"))

type Seconds = Int
data Run = Run { playerName :: Maybe String, userLink :: Url
               , time :: Seconds, video :: Url} deriving (Show)
instance FromJSON Run where
    parseJSON (Object o) = Run
        <$> (player >>= (.:? "name"))
        <*> (player >>= (.: "uri"))
        <*> (run >>= (.: "times") >>= (.: "primary_t"))
        <*> ((head <$> (run >>= (.: "videos") >>= (.: "links")))
            >>= (.: "uri"))
        where
          run    = o .: "run"
          player = head <$> (o .: "run" >>= (.: "players"))

parseRun :: Int -> Json -> IO (Either String Run)
parseRun place json = do
    runData <- (eitherDecode <$> json) :: IO (Either String RunData)
    return $ runData >>= \runData -> return $ runs runData !! place

example.rs

fn parse_run(json: &Json) -> Run {
    let data = json.as_object().unwrap()
                   .get("run").unwrap().as_object().unwrap();
    let user_name = {
        let player = data.get("players").unwrap().as_array().unwrap()
                         [0].as_object().unwrap();
        let user_type = player.get("rel").unwrap().as_string().unwrap();
        match user_type {
            "user"  => {
                let url = player.get("uri").unwrap().as_string().unwrap();
                fetch(url, &parse_name).unwrap()
            },
            _ => player.get("name").unwrap().as_string().unwrap().to_string()
        }
    };
    let time = data.get("times").unwrap().as_object().unwrap()
                   .get("primary_t").unwrap();

    let video = data.get("videos").and_then(|links|
                    links.as_object().unwrap()
                         .get("links").unwrap().as_array().unwrap()
                         [0].as_object().unwrap()
                         .get("uri").unwrap().as_string())
                         .map(|s| s.to_string());
    Run{ user_name: user_name
       , time: time.to_string()
       , video: video }
}