Ending Dependency Chaos: A Proposal for Comprehensive Function Versioning

E.g. suppose that there is a new version of pthread_mutex_lock(&mutex) which relies on a larger structure with new members in it. Problem is that compiled programs have pthread_mutex_lock(&mutex) which pass a pointer to the older, smaller structure. If the library were to work with the structure using the new definition, it would access out of bounds. Versioning take care of this; the old clients call a backwards compatible function. It might work with the new definition, but avoids touching the new members that didn't exist in the old library.

But this is a very low-level motivation; this same problem of low-level layout information being baked into the contract shouldn't exist in a higher level language.

I don’t know what’s everyone else’s experience but I was updating dependencies due to either bugs identified in old versions, because I wanted a new feature or because the old version was not supported anymore. Setting dependency to a fixed version was not an option. Using in your code function with given version fixed seems to be problematic.

During updates the problem was to update all other dependencies as a result of the update. I can’t see how the proposed approach would solve it.

Another problem which I sometimes faced (less annoying) was the api change i.e. start using function B instead of function A which requires slightly different parameters. Those kind of automatic refactors could be supplied with library upgrades (some libs already come with automatic migration “scripts”)