Dear all, 

I'd like to suggest we introduce the following very useful feature, as soon as 
possible (which likely means in the next EAPI?):

* two new files in profile directories supported, package.use.stable.mask and 
package.use.stable.force
* syntax is identical to package.use.mask and package.use.force
* meaning is identical to package.use.mask and package.use.force, except that 
the resulting rules are ONLY applied iff a stable keyword is in use

Rationale: Often single features are "not ready for production yet", but the 
remaining package with that feature disabled would be a perfect candidate for 
stabilization. Right now this can be solved by 
* masking the useflag, which then makes the feature inaccessible even for 
~arch
* masking the useflag for exactly one package revision, which is hell to 
maintain
* or introducing different package revisions with/without the useflag, which 
is also a mess. 

Where this would (have been|be) useful:
* we had for a long time different revisions of subversion with/without kde 
useflag
* cups-1.4 had the infamous libusb backend triggered by USE=usb
* cups-1.5 has optional systemd support via a systemd useflag, which pulls in 
non-stabilized systemd as dependency...

Cheers, 
Andreas

-- 

Andreas K. Huettel
Gentoo Linux developer 
dilfridge@g.o
http://www.akhuettel.de/