8 May
2008
8 May
'08
12:55 p.m.
On Thu, 8 May 2008, Mark Wallsgrove wrote:
Problem now is reading the data back into the program. When I read the data back into the program it comes as IO [Track]. This is the code I have been using to load the data:
loadData :: String -> Catalogue loadData fileName = do x <- readFile fileName return (read x :: Catalogue)
type should be loadData :: String -> IO Catalogue But using plainly 'read' may not satisfy you, because the program will abort unrecoverably if the file has corrupt content. You may want to use 'reads' and check manually if parsing was successful: case reads x of [(cat, "")] -> return cat _ -> fail "corrupt file content"