Re: swh-plugins-lv2: New variable [WIP] v2

[ludo@gnu.org (Ludovic Courtès)]

Mark H Weaver <mhw@netris.org> skribis:

> Ricardo Wurmus <rekado@elephly.net> writes:
>
>>> +(define-public swh-plugins-lv2
>>> +  (let ((commit "5098e09e255eaed14e0d40ca5e7e6dfcb782d7ea"))
>>
>> We usually don’t use full commit hashes.  You could probably trim it to
>> the first six characters or so.
>
> I would recommend using at least 10 characters, maybe more.  We should
> use enough characters to ensure that the commit id remains unique for as
> long as this package version remains in use -- keeping in mind that for
> purposes of reproducing old experiments, someone might try to build this
> package+version several years from now.

I sympathize with this.  I would think 10 digits is more than needed,
though: With 6 hex digits, it takes on average 16^6 = 16M commits before
the 6-digit ID is ambiguous, and with 8 hex digits that goes to
4 billion commits (Emacs has around 123,000 commits as an example.)

But anyway, to be super-safe, we could use the full SHA1 in the URL, but
strip it in the ‘version’ field so that it remains readable.

Thoughts?

Thanks,
Ludo’.