Contradictory justification for status quo

[Zach the Mystic via Digitalmars-d]

On Friday, 27 February 2015 at 02:58:31 UTC, Andrei Alexandrescu 
wrote:
> I'm following with interest the discussion "My Reference Safety 
> System (DIP???)". Right now it looks like a lot of work - a 
> long opener, subsequent refinements, good discussion. It also 
> seems just that - there's work but there's no edge to it yet; 
> right now a DIP along those ideas is more likely to be rejected 
> than approved. But I certainly hope something good will come 
> out of it. What I hope will NOT happen is that people come to 
> me with a mediocre proposal going, "We've put a lot of Work 
> into this. Well?"

Can I ask you a general question about safety: If you became 
convinced that really great safety would *require* more function 
attributes, what would be the threshold for including them? I'm 
trying to "go the whole hog" with safety, but I'm paying what 
seems to me the necessary price -- more parameter attributes. 
Some of these gains ("out!" parameters, e.g.) seem like they 
would only apply to very rare code, and yet they *must* be there, 
in order for functions to "talk" to each other accurately.

Are you interested in accommodating the rare use cases for the 
sake of robust safety, or do you just want to stop at the very 
common use cases ("ref returns", e.g.)? "ref returns" will 
probably cover more than half of all use cases for memory safety. 
Each smaller category will require additions to what a function 
signature can contain (starting with expanding `return` to all 
reference types, e.g.), while covering a smaller number of actual 
use cases... but on the other hand, it's precisely because they 
cover fewer use cases that they will appear so much less often.