[Nix-dev] Question about organising dependencies not in core nixpkgs?

[Thomas Hunger]

Apologies, here's the rest of my email:

.. but I could not find anything that looks like "evaluate at build time" -
is that code somewhere public?

Thanks,
Tom

[1]
https://github.com/shlevy/nix


On 18 March 2015 at 16:01, Thomas Hunger <tehunger at gmail.com> wrote:

> Hi Shea,
>
> I checked your github version of nix [1]
>
>
> [1]
>
>
> On 18 March 2015 at 14:39, Shea Levy <shea at shealevy.com> wrote:
>
>> You can already do this. “import foo” will build any derivations that
>> “foo” depends on at evaluation time.
>>
>> Note though that really “build at evaluation time” is for several reasons
>> inferior to “evaluate at build time”, i.e. recursive nix. I have an
>> implementation for that but it doesn’t look like it will be accepted.
>>
>> ~Shea
>>
>> On Mar 18, 2015, at 8:36 AM, Kirill Elagin <kirelagin at gmail.com> wrote:
>>
>> I’d say there is a more general problem.
>>
>> Imagine, that one day [in a far far away future] people start shipping
>> derivations in `default.nix` in their sources (I guess people who develop
>> on NixOS/with nixpkgs already do this as they have the file for their build
>> environment anyway, so why not commit it). And then we have two copies of
>> derivations: in the source repository and in `nixpkgs`.
>>
>> So it really looks like having something like `fetchDerivation("…url…")`
>> would be handy. This function should fetch the source, unpack it, extract
>> `default.nix` and use it as derivation to build the already fetched source.
>> This way the `nixpkgs` repository itself is not required for packages that
>> have this kind of information shipped and other projects can depend
>> directly on the urls of repos. Then nixpkgs could be thought as a database
>> of “well-known” packages with their urls.
>>
>> On Wed, Mar 18, 2015 at 2:53 PM Luca Bruno <lethalman88 at gmail.com> wrote:
>>
>>> On 18/03/2015 12:37, Thomas Hunger wrote:
>>> > Thanks.
>>> >
>>> > That would require having the shell.nix library locally already
>>> > AFAICT. To rephrase slightly. Ideally I'd like to be able to do:
>>> >
>>> > myLibrary = fetchurl { ... };
>>> > extraDepends = import "${myLibrary}/depends.nix";
>>> > buildDepends = [ ... ] ++ extraDepends;
>>> >
>>> > Does that make sense?
>>> I understand that, but I think the best fit of nix usage is having all
>>> the nix expressions in the same repository, instead of spreading nix
>>> files on every repository. That is, what's nixpkgs is doing.
>>>
>>> So I would create a repo of all nix files, which fetch sources from your
>>> other repos.
>>> _______________________________________________
>>> nix-dev mailing list
>>> nix-dev at lists.science.uu.nl
>>> http://lists.science.uu.nl/mailman/listinfo/nix-dev
>>>
>> _______________________________________________
>> nix-dev mailing list
>> nix-dev at lists.science.uu.nl
>> http://lists.science.uu.nl/mailman/listinfo/nix-dev
>>
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.science.uu.nl/pipermail/nix-dev/attachments/20150318/f163b937/attachment.html