https://github.com/atilaneves/DIPs/blob/editions/editions.md

On Tuesday, 1 April 2025 at 16:21:59 UTC, Atila Neves wrote:

Glad to see you are still working on this.

Two lines might need some clarification:

1. "One possibly way to bound this complexity could be to only support the last N editions, for N < 5."

2. "The editions feature is explicitly designed with the goal of not introducing any breaking changes or deprecations. Existing D code that does not opt-in will continue to compile as behave as before."

My reading is that if you don't opt-in to a specific edition, then you use the current edition. So #2 is a little confusing because if new editions introduce breaking changes, then you have to opt-in to use the prior edition to avoid the breakage.

If you have opted-in to editions and you are only keeping around the last N editions, then when the number of editions is larger than N, support for initial editions will get dropped. This also implies that there will be breaking changes/deprecations.

If you really want to avoid breaking changes/deprecations, you can also keep last N editions plus the initial edition. You can also optionally strike new ones every couple of years that are meant to be kept around. That last bit depends on how often we get these new editions.

In the paragraph below you say "current original edition" but I think you just mean "current edition". The last sentence could probably be folded into the first sentence, or otherwise simplified since it covers a bit of what is in the first sentence.

Existing modules without this optional declaration but that have a module declaration are considered to target the current original edition. That is: they will be compiled as if the editions feature did not exist. Modules without a module declaration would be considered to be using the latest edition unless the default edition is specified explicitly with a command line argument.

On Tuesday, 1 April 2025 at 16:21:59 UTC, Atila Neves wrote:

D is not go/rust/c++/c#, can it afford this much maintenance burden that editions will bring? I personally don't think so

On Tuesday, 1 April 2025 at 16:21:59 UTC, Atila Neves wrote:

Why? I see no reason that they shouldn't behave like the modules with editionless declaration at the top.

Does this override the edition at the module declaration?

Of course they have to support the new edition, but why would they have to transition to the edition themselves? Seems extra work for no good reason.

All in all, I strongly support this DIP.