Re: [gentoo-dev] Parsable list of all use variables.

[George Shapovalov <georges@its.caltech.edu>]

Isn't there one already?
/usr/portage/profiles/use.desc

The format cannot be simpler:
usevar - description
Is there any problem with parsing that? Even cut -d "-" would do it (not to 
mention awk and python).
This list is not enforced at present (that is if usevar is not listed there it 
will still be considered valid), but that can change at any moment.

As for the list of packages that use that var: that is going to be the largest 
problem. This tends to be very dynamic, also I would be hesitant to put that 
into use.desc as this will overload it (however technically this is very 
simple: just add one more delimeter and then list packages using this var 
(whitspace or comma separated))
There was a discussion on introducing IUSE into ebuilds which is supposed to 
list all use var that ebuild references. However there was not much activity 
on that. Also it is just possible to scan ebuild for "use XX" clauses and 
thus extract all referenced usevars.
I guess my point is that such back-reference list of packages referencing 
usevars can easily be dynamically reconstructed, and that I think is better 
solution than hand-maintained list.

George


On Thursday 09 May 2002 10:16, Bob Phan wrote:
> On Thu, 9 May 2002, Francisco Gimeno wrote:
> > and... going on work... we could make the same to the commands of the
> > ebuild packages, like dodir, doins, and those... to get them
> > well-documented and in an ordered way...
>
> I don't follow?  The goal isn't to make an xml ebuild, as I rather
> like them as shell scripts and it lowers the bar a little for people
> that wan't to start writing their own.  The design goels for what I
> suggested, is basically a way to keep track of all currently used USE
> vars.  And basically, three things are important about each.
>
> 1) What they are called.
> 2) What they mean.
> 3) Which packages use them.
>
> I think it would be a valuable resource to have a maintainable and
> parsable list of these.  As it stands, I already have a perl script
> that can dig out 1 & 2 and dump them into XML.  I'm going to tidy it
> up a bit and probably post it to this group.