[Nix-dev] Fwd: Re: Displaying package parameters

[Fabian Schmitthenner]

On 03/05/2016 07:13 PM, jeaye wrote:
> On Mon, Feb 29, 2016 at 11:24:32AM +0100, Jonn Mostovoy wrote:
>> Wow, very nice!
>> Maybe people reporting that it doesn't work weren't patient enough to wait
>> for it to load the entirety of packages ;)
> If I load the page, wait 5 minutes (should be long enough...), and type
> 'firefox', I can select the 'firefox-44.0.2' option and still see:
>
> error     some error happened
>
> This clearly isn't a matter of being impatient.
Yes, you're right. This doesn't work for derivations that don't use
lib.makeOverridable (which callPackage implicitly uses) and currently
this (misleading) error message is shown in this case which I'll change
to something more descriptive.

I investigated this particular case (firefox) and we don't use
makeOverridable at the moment (because wrapFirefox doesn't use it). When
we change wrapFirefox to also use makeOverridable then this should work,
too. Currently, firefox also has no .override attribute (because it
doesn't use makeOverridable) and I believe this to be a bug.

But we already use lib.makeOverridable (by callPackage) for
'wrapFirefox' itself, so maybe we can also add some more functor logic
to makeOverridable to do this. We really have two layers of parameters.
But I have to think about that a little more.

Fabian
>
>> I just wanted to share that I tried displaying package parameters on the
>> nixos homepage and the current result can be seen here:
>> http://schmitthenner.eu/nixos-homepage/nixos/packages.html.
> This is superb. As mentioned, there are still some errors with common
> packages, but this is already very useful. Thanks for the work and for
> providing the source.