[xmonad] darcs patch: Add a LayoutCombinator class and a CombinedLayout and ...

[Andrea Rossato]

On Tue, Jan 29, 2008 at 05:33:04PM -0500, Brent Yorgey wrote:
> On Jan 29, 2008 2:57 PM, Andrea Rossato <mailing_list at istitutocolli.org>
> wrote:
> 
> > On Tue, Jan 29, 2008 at 08:41:28PM +0100, Andrea Rossato wrote:
> > > Tue Jan 29 20:29:03 CET 2008  Andrea Rossato <andrea.rossato at unibz.it>
> > >   * Add a LayoutCombinator class and a CombinedLayout and port
> > PerWorkspace to the new system
> >
> > just to let you know that this will be amended. I'm going to remove
> > the necessity of implementing doFirst (it was needed just to decide
> > which layout description to use)!
> >
> 
> Yes, this is a problem with PerWorkspace in particular -- the description
> method is pure, but the chooser method must be in the X monad to have access
> to the current stackset, in order to figure out which workspace is current.
> So in order to get the description method right, the decision of chooser
> must be cached as part of the data type so that description can show the
> description for the correct layout.  This is what PerWorkspace used to do.

sorry, my previous mail was probably sent too early (I'm tire after a
day of type class hacking :)... 

yes, the fact that we need to implement the "chooser" inside the X
monad is a bit ugly. Originally i though it as a pure method, and I
changed it because I could not implement PerWorkspace, otherwise.

If you can come up with a cleaner solution that would be graet.

sorry for the noise.... i'm going to bed now.

Andrea