Conan: Opt-in global full_version instead of semver for package_id

[lasote]

Consider adding an opt-in mechanism using the conan.conf to change the global behavior of the package_id method to default all packages (only default, not override if they have fine adjustments) so we can change the default semver to default full_version, that would be the default in Conan 2.0

Probably we should consider the default being configurable => full_package_id, full_version...

[puetzk]

I'd also really like to see this on a per-package basis, where a package could declare how strictly it maintained binary compatibility and have that change its default representation in a consumer's info.requires["x"]. Obviously the consumer's package_id function could still change this, but in general "which versions are binary compatible" is something better known by the libfoo recipe than by the consumer.

[niosHD]

I agree, having the possibility to define the default binary compatibility (for consumers) within the package itself would be great. I have already encountered some difficulties due to the lack of this feature. (see #3318)

[lasote]

@puetzk @niosHD Could you please open a new issue for that? you can reference this. There are two clearly different issues and won't be implemented together (we have first to agree on what you are suggesting). That is the only way we don't lose it when I close this one as "done".

[niosHD]

3318 should suffice, doesn't it? I just referenced my issue since I wanted to establish the link and to make it easier discoverable it in the future. I think the suggestion that I make in https://github.com/conan-io/conan/issues/3318#issuecomment-411717193 is exactly the same what @puetzk is asking for.

[lasote]

You are right.

[puetzk]

Yes, I agree #3318 seems like a good discussion of the same issues I had in mind with libraries that do not use semver. I've subscribed on that one.