[Rd] Declaring Types at Function Declaration

[Simon Urbanek]

> On 28 Nov 2025, at 07:32, ivo welch <ivo.welch using ucla.edu> wrote:
> 
> thank you, everyone.  it seems to me from the outside that the key aspect that is missing is the core R team having an interest and taking the lead on something...anything.
> 

Wow, I guess you're using R 1.0.0 then? I don't think anyone managed to insult all the hard-working volunteers that evolved R continuously for over 25 years just as badly. Maybe you should look into the "new features" sections of the NEWS files?


> I am not an R developer, just a medium-sophisticated occasional R end user in the trenches, and not a very good one at that.
> 
> so, in my trench, I would love anything that makes code easier to read and bugs earlier and easier to find.  Jan's proposal seems great.  if integrated into the language, perhaps with an option to either ignore the checks or issue warnings when functions are not annotated, they would make my code better and my life easier.  it would be even better if R in general migrated to it, so everyone understood that this is the better way to write code.  sort of like conventions for indentations.
> 
> Josiah has amazing discipline to put all the checks into his functions that I wish I had.  alas, this greatly reduces readability of the function in my mind.
> 
> again, it seems to me that it is the R core team that needs to decide…and I think they decided it isn't worth it.  this is why they are paid the not-so-big bucks.  I view how they decided as a pity, but it isn't me but the people who do the work that should decide.
> 


What should we decide on? There are many much more pressing issues being implemented or ideas considered for R. Optional typing has no immediate benefit, it is a cool, but ill-defined idea precisely because of the open questions about what it should do. Would you want me to simply have merged the R5 branch to satisfy your "take the lead"? I don’t think it would be a good idea to have no discussion. Similarly, it is not uncontroversial as is clear from the very good responses here that raised the important points, so thanks to these that responded constructively. That doesn't mean that R core has decided anything in that regard. R is open source so anyone can make suggestions and try them out. R core has no monopoly on ideas, there are certainly features in core R that have been contributed by others in the past. The only condition is that they are well thought through, since changes in core R cannot be undone easily, so that's why it typically requires a robust discussion first. I thought that’s exactly what we are having here which is the first step if you want to introduce something.

Cheers,
Simon