On 2004-10-25, Peter Simons
John Goerzen writes:
Now, if [I read with hGetContents h], then the first read I try to make using it works, but subsequent ones don't, since the first one made it half-closed already.
Maybe I misunderstood something ... but why do you need to read from the stream multiple times after calling hGetContents? The function returns the _entire_ (lazily evaluated) input stream, there is no need to read again. You already _have_ everything.
Because I'd have to use a state monad or something to chop off the top of the list each time I read from it. This is a FTP client module, so, for instance, you might see this session: cwd h "/pub/linuc" nlst h Nothing etc. Each command sends something and reads a reply. "h" holds an instance of that data structure I posted. If I just try to read from the list during each command, I would just read the same (first) response over and over again. Or, I'd have to store a position (which also requires a state monad), which would lead to wasting memory keeping all that stuff around.