On 8/16/08, Antoine Latter
The following is a summary of my plan so far. I'm interested in hearing any suggestions or concerns about what a Haskell library for writing X clients should look like. This is not a release announcement, and I can't make any promises about when this will be delivered.
Code is available in darcs: -- darcs get http://community.haskell.org/~aslatter/code/xhb
Some of the advantages XCB claims over xlib are: + smaller API + latency hiding when communicating with the X server + direct access to the X protocol + improved threading support + easier to extend
What I plan for the X Haskell Bindings (XHB) are as follows:
It seems to me that you could make this a bit more haskelly...
+ All requests to the server are non-blocking (under most circumstances)
+ Requests which produce a reply from the server return a "token" or "receipt"
Why not abstract this token or receipt into a function? i.e. why not change...
-- | List all of the extensions supported by the server listExtensions :: Connection -> IO (Receipt (ListExtensionsReply))
-- | Query a receipt for a response getReply :: Receipt a -> IO (Either XError a)
to listExtensions :: Connection -> IO (IO ListExtensionsReply) and then you don't need to use a getReply, or a Receipt data type. This should be equally general, if (as I imagine) the only thing you can do with a Receipt is to getReply it. And to me it seems like a friendly way of describing what this function does.
Each X extension defines its own set of errors and events (potentially). Should all of these be lumped together into one giant sum-type for errors and one for events?
Or maybe just a couple of existential types together with dynamic? (i.e. like xmonad's SomeMessage) David