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

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

Hi Bob

short update on a situation.

On Monday 13 May 2002 06:31, Bob Phan wrote:
> > This regex handles those cases:
> >
> > ^([a-z0-9]+)[ \t]+-.*
> The problem with that regex is it only strips out the use variables.
This regexp is used by lintool at present to extract a list of use vars out of 
use.desc file. This in a sense enforses present format, however this is only 
one tool of which I know that actually parses use.desc at this point.
(and BTW, as it works, lintool will just ignore all run-over description 
lines, which is fine for the tool but is a bad idea if you want to get hold 
on descriptions as well. Thus I think single line per usevar entry should be 
enforced).

Also there were/are plans to assign values to usevars, for example:
arch = (ppc|sparc|x86)
gnome = 1.4

So far this was the only addition mentioned, so this will be possible to 
accomodate in a single human-readable file by slightly changing the format. 
Probably something of the form:
usevar = (list|of|values); description
can do.

However please understand that these are just that - plans, so old format 
(usevar - description\n) is now in force and I expect will be for some time.
As far as policy goes, the word was that there isn't real one. Basically it 
goes as far as it gets enforced by accepted tools, in this case lintool 
(which only checks for "usevar -" part anyway). If your script gets accepted 
it becames a new policy ;). However in order for it to be accepted it should 
peacefully coexist with lintool, therefore it would be a good idea to consult 
lintool code whenever you are uncertain about any USE-related formats).

George