Versioning

On 17 Nov 2021, at 15:12, Eric Timmons wrote:

On 11/17/21 2:38 PM, Robert Goldman wrote:

...

On 17 Nov 2021, at 13:31, Robert Dodier wrote:

On Wed, Nov 17, 2021 at 10:45 AM Robert Goldman 

rpgoldman@sift.info mailto:rpgoldman@sift.info wrote:

    I favor something like this because it would be nice to have
    prerelease versions of ASDF that perform version checks 

properly.

    What I mean is, if we are going to add a feature in version 

3.4, right now that would be in a prerelease version with a version number of something like 3.3.5.22

    It would be a lot better for realistic testing if we could
    instead use 3.4.0-alpha1 or 3.4.0-1 and have ASDF know that
    3.4.0-1 comes before 3.4.0, not after.

Hi Robert, hi everyone. I haven't been following closely, but 

while you are working out details, let me just mention that I recommend against version numbers that require special interpretation to discover their ordering, e.g. 3.4.0-1 < 3.4.0.

Mostly I'm just thinking that somebody's not going to get the 

memo (it's usually me).

For what it's worth, and all the best.

I guess that would be an argument for using something more obvious than |-|, like the string |alpha| so |3.4.0-alpha1| or |3.4.0alpha1| instead of |3.4.0-1| since there the meaning should be relatively obvious.

My feeling is that if a user misinterprets |3.4.0-1|, then shame on me. But if a user misinterprets |3.4.0alpha1| then shame on them.

I'm not sure how that would align with semver...

Erik already sent out some examples of ordering with semver. But it is worth noting that 3.4.0-1 *is* valid semver and the ordering would be 3.4.0-1 < 3.4.0-alpha

So to prevent misinterpretation of 3.4.0-1, ASDF could either promise to always use something like alpha/beta/etc, use something else like PEP440 (I believe that grammar always requires an alphabetic character for pre-releases), or bake its own grammar.

One thing that's nice about the semver grammar is its flexibility. I have some scripts that can generate a version string from a git repo that lets you easily order versions based on things like when they branched off the default branch. But if we want ASDF to disallow things like 3.4.0-1, I'm happy to build my own system that uses the new API to allow the use of semver strings.

Another option is to choose something compatible with Debian's version strings. I'm having a little trouble grokking it at the moment, but it seems to be even more freeform than semver and adds an optional epoch prefix.

What might be nice would be to support a *subset* of semver by default -- not allowing the numerical prerelease flagged with `-` -- but do so in a way that is extensible.

Here's my rationale: I would like to provide a relatively simple semantic versioning that is also compatible with automatically detecting and rejecting ill-formed version strings.

So, for example, we could (by default!) split the version strings by `#.` and `#-` and *reject* any string bounded by `#.` that is not numerical.

We could demand, again by default, that the substring following the `#-` be of some constrained form: e.g., Greek letter name followed by optional numeral. For that matter, we could just say "hey, alpha and beta are enough" and reject anything but those two. That would be a nice alternative to having a big table of Greek letter names in ASDF!

Finally, for those who want to really go for it, we could add a `:version-scheme` keyword to `defsystem`, which would initially default to `:unconstrained`, but then through the standard process of warning and then erroring, migrate to `:standard` (or perhaps `:asdf`) as the default, but let anyone who wants to make up their own versioning scheme. `semver` would be an obvious extension.

Hm. That's a bit more complex than I had hoped, but it would mean ASDF systems would initially continue to work, it provides for some error checking, and a path to extension.