[Slackbuilds-users] OPTIONAL field [was: qemu/spice-gtk and usbredir]

[Ythogtha]

> On 06/11/16 03:51, Erik Hanson wrote:
> > The goal is then that no one would
> > ever have to look at the README file, they could just tick some boxes
> > and be on their way.
> 
> No, that's not the point. At least not mine.
> The point is to facilitate the process.
> And you can't argue that for _educated_ user it is going to be.
> 
> But as you mentioned before, we might have problem with _education_ 


	My own use-case for an OPTIONAL field would be to alert me when there is
an update available for an installed package, which happen to be an OPTIONAL
dependency for another package I have installed.
	Quite the same as the actual REQUIRE : when a REQUIRED package has an
update, I list the installed packages which depends on it.
	This allows me to decide if I want to rebuild the package for which the
dependency changed, even if it hasn't changed itself.

	It had happened to me on occasions that ffmpeg stopped working because I
updated an OPTIONAL dependency, I was actually thinking about GREPing on the
READMEs to find those OPTIONAL dependencies, because it sucks when ffmpeg is
broken like that, and there is no easy way to know in advance in the general case
(I could do something specific for ffmpeg, but that's not the point, and there
are other packages with OPTIONAL dependencies, though none with as many as
this one).
	It could even happen while we aren't even aware we had an OPTIONAL
dependency, because some packages detects them automatically, and we could have
an OPTIONAL package already installed, hence linked into a new one without being
really aware of that : no step about it was taken, and we might not even need the
OPTIONAL part, but it's there, therefore used.

	For my own use-case, a simple list of possible OPTIONAL dependencies is
clearly enough, because I will read the READMEs, and know what to do, but I have
no direct way of automatically knowing what will be impacted by a package update.

	I think this is something that could be useful to everybody. It doesn't
change much, basically a tool would add OPTIONAL dependencies to REQUIRE ones
when they are already installed, for the purpose of presenting to the user what
might need rebuilding after an update, or even what packages might depend on
another one if we want to remove it :
« Hey, this package isn't REQUIREd by any of your installed packages, but is
OPTIONAL for this one, are you sure you want to remove it ? »
	Or in my case a script "is_this_package_required PKGNAME" reporting when
the package is REQUIRED and OPTIONAL.


	Those are thoughts about the usefulness of the OPTIONAL field completely
out of an automatic building process with checkboxes and automatic dependencies
checking and building.

-- 
Arnaud <yth at ythogtha.org>