On Fri, Mar 9, 2018 at 6:39 AM, Maxim Ivanov <ivanov.ma...@gmail.com> wrote: > > Side question, would hyptohetical future generics substantially > reduce number of API breaking changes?
I don't really see how. In a language like Go, I think that any plausible definition of generics implies adding type parameters to a function. Although those parameters may be specified in many different ways with many different possible restrictions, at base they amount to another kind of parameter, albeit one that is evaluated at compile time rather than at run time. Any change in those parameters, however specified, is going to be an ABI breaking change. (I would be interested in hearing of any language that implements generics in a way that maintains compile-time type checking but does not involve some sort of type parameters.) I'll note that while Axel's writeup is good, I personally would be willing to treat adding a new field to a struct type or a new method to a non-interface type as a non-breaking change. It's true that it can break people embedding types, but unless the docs specifically encourage embedding types I think that is a sufficiently unusual case that I wouldn't worry about it. Which just goes to show that there is indeed disagreement on these points. For what it's worth, https://golang.org/doc/go1compat does specifically permit adding fields and methods, while acknowledging that that has the possibility of breaking code. Compatibility of course goes beyond function signatures, it goes to behavior. In the limit, it becomes impossible to make any user visible change to a package, because of Hyrum's Law (http://www.hyrumslaw.com/). So while some changes clearly break the ABI, and a few clearly do not, there is still a large grey area. Ian -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
