[Haskell-cafe] Re: Doing without IORef

[Bryan O'Sullivan]

Jinwoo Lee wrote:

> To summarize, embed IORef inside ReaderT and use that IORef to
> read/change the file path info, both in IO monad and MyState monad. Is
> this right?

Yep.  In case you ever want to multithread your program, you might want
to use an MVar instead of an IORef.

	<b