Hi, Am Freitag, den 15.02.2013, 14:50 +0000 schrieb Simon Marlow:
On 15/02/13 12:22, Joachim Breitner wrote:
Hi,
more progress: On top of base-pure, I created base-io involving GHC/IO and everything required to build it (which pulled in ST, some of Foreign and unfortunately some stuff related to Handles and Devices, because it is mentioned in IOException). This is the list of modules:
You have a random collection of modules here :)
I think you want to have the IO *monad* (GHC.IO) live in a lower layer, separate from the IO *library* (GHC.IO.Device and so on). Every Haskell implementation will need the IO monad, but they might want to replace the IO library with something else.
Things like GHC.IORef, GHC.MVar can all live in a low-down layer because they're just wrappers over the primops.
Right, that is my aim, and I started with GHC.IO. But unfortunately, the IO monad calls failIO, which is an IOError which has a field of type ioe_handle :: Maybe Handle (and one of type CInt) which pulls in all the rest there, and so far I did not have a good idea how to untangle that. What would break if fail would not raise an IOError, but a separate exception type, e.g. IOFailError? Probably too much, as users expect to catch the exception raised by fail with an exception handler that matches IOError. Greetings, Joachim -- Joachim "nomeata" Breitner Debian Developer nomeata@debian.org | ICQ# 74513189 | GPG-Keyid: 4743206C JID: nomeata@joachim-breitner.de | http://people.debian.org/~nomeata