John Goerzen wrote:
My proposal is here:
http://www.complete.org/~jgoerzen/t/MissingH.IO.HVIO.html
I'm aware that others have been working on IO proposals; specifically, Simon Marlow's here:
The proposal on Simon M's page was originally my design, though Simon made many improvements. You can read my rationale for the original design in these mailing-list messages: http://www.haskell.org/pipermail/haskell/2003-July/012312.html http://www.haskell.org/pipermail/libraries/2003-July/001255.html http://www.haskell.org/pipermail/libraries/2003-July/001257.html http://www.haskell.org/pipermail/libraries/2003-July/001273.html http://www.haskell.org/pipermail/libraries/2003-August/001319.html http://www.haskell.org/pipermail/libraries/2003-August/001336.html http://www.haskell.org/pipermail/libraries/2003-August/001366.html I had to abandon many of the original ideas because the Posix and Win32 APIs can't support them. (Some examples of things you should be able to do, but can't in Posix or Win32: given a directory handle and the name of a file in the directory, open that file; given a file handle with read access, acquire write access if available; conduct atomic filesystem transactions.) The most important idea that survives is the separation of files from input streams and output streams, Given this background you can probably guess that I'm not too keen on the traditional open/read/write/seek/close model; I don't think it's a good abstraction for anything, even files. I love the idea of gzip and gunzip as transformations on streams, though, and streams backed by memory buffers appear in my proposal too.
* Would I be better advised to try to implement some existing ideas instead?
Yes, you should definitely spend your time implementing my pet idea, not yours. :-)
* Are there any other implementations of these things that are ready to use? (With code)
Simon wrote a prototype implementation of his/my proposal: http://www.mail-archive.com/haskell-cafe@haskell.org/msg05138.html -- Ben