Loop invariants

[Dukc]

On Friday, 27 September 2024 at 18:10:13 UTC, Quirin Schroll 
wrote:
> In spirit of [this issue 
> comment](https://issues.dlang.org/show_bug.cgi?id=9300#c4), but 
> here with better syntax.

Would these invariants be used often? Personally I find that my 
assertion usage is almost exclusively plain assertions, in 
contracts and unit test assertions. I rarely end up using the 
type invariants. I think it'd be even rarer for me to use the 
loop invariant. For me personally, this would be needless 
complexity.

Maybe it's just me though. What do others think? Do you use (or 
would you use, given some kind of project) assertions so 
aggressively that you feel this would improve the language?

`invariant` is already a keyword and this isn't much different 
from how the existing contracts work so it wouldn't a complex 
feature. I therefore think that a significant minority who would 
benefit from this would be enough justification for the feature. 
It doesn't have to be over 50%.