How to tell which repositories provide which packages?

[Little Girl]

Hey there,

Ralf Mardorf via ubuntu-users wrote:
>Little Girl wrote:

>>It looks like it must be an unsigned integer, but it can be ommitted
>>and, if so, is assumed to be a zero:
>>
>>https://www.debian.org/doc/debian-policy/ch-controlfields.html#s-f-version  
>
>Thank you for doing this work. It's still not clear to me.

It could definitely have been handled better in the man page.

>The epoch must start with a digit, but most packages don't use an
>epoch at all. 

Technically, they all do, but most don't display one.

>"The upstream_version may contain only alphanumerics [6] and the
>characters . + - ~ (full stop, plus, hyphen, tilde) and should start
>with a digit. If there is no debian_revision then hyphens are not
>allowed."
>
>"[6] Alphanumerics are A-Za-z0-9 only."
>
>"should start" but IIUC they could start with a letter.

Yes. They could also start with one of the allowed characters.

>A-Za-z seems to exclude umlauts and other exotic signs.

Probably, since most of us have to press more than one key at once to
create those.

>IIUC theoretically it could even start with a full stop, plus, or
>tilde.

Or a hyphen.

>IOW usage of "[:alnum:]" is likely better than usage of "[:digit:]",
>probably no package version starts with a full stop, plus, or tilde,
>but perhaps with "alpha", "beta", "git", "af12de" hex numbers etc.

I don't know, but since it's allowed to start them with things other
than digits, it needs to be taken into account that they might in case
someone decided to go for it.

-- 
Little Girl

There is no spoon.