bug#41294: [PATCH] gnu: Add libfreenect.

[iyzsong@member.fsf.org (宋文武)]

Ekaitz Zarraga <ekaitz@elenq.tech> writes:

> ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
> On Wednesday, May 20, 2020 3:33 PM, <iyzsong@member.fsf.org> wrote:
>>
>> Um, I mean something like this:
>>
>> (define libfreenect-derived-phases
>> '(modify-phases %standard-phases
>> (lambda* (#:key outputs #:allow-other-keys)
>> ...)))
>>
>> ...
>> (arguments
>> `(#:phases ,libfreenect-derived-phases))
>> ...
>>
>> Here 'libfreenect-derived-phases' is a list of symbols, the arguments
>> field we want is a list of symbols too.
>
> Hi,
>
> That makes way more sense than what I was trying to do.
> I applied that and separated libfreenect to a different module. Patch below.

Pushed, with:
- Change libfreenect-python to 'python-libfreenect'.
- Change libfreenect-cv to 'libfreenect-opencv'.
- Change some comments..

Thank you!

>
> Thank you very much for your support.
>
> PS: I'm still wondering what kind of weird magic is involved in the example I shown.
>

Basically we can't use procedure (defined outside of the builder
environment) values in the package's arguments field, it have to be self
contained, as the package builder is a guile script file serialized from
the package object (procedures serilazied into #<procedure ...>, and
can't be loaded again), and will be executed in an isolated environment.