sdfsdf.idr

module Foo


import System.File
import Control.Monad.Managed

export
withFile' : HasIO io => String -> Mode -> (Either FileError File -> io a) -> io a
withFile' file mode act = do res <- openFile file mode
                             a <- act res
                             either (\_ => pure a)
                                    (\f => pure a <* closeFile f) res

main : IO ()
main = do
  putStrLn "No files are open"
  runManaged $ do
    f1 <- managed $ withFile' "/dev/urandom" Read
    putStrLn "f1 is open"
    f2 <- managed $ withFile' "foo.txt" Read
    putStrLn "f2 is open"
    dosomethingwith f1
    dosomethingwith f2
  putStrLn "No files are open"