Better error messages - from reddit

[Atila Neves]

On Monday, 4 March 2019 at 16:49:25 UTC, Sebastiaan Koppe wrote:
> On Monday, 4 March 2019 at 15:47:12 UTC, H. S. Teoh wrote:
>> [...]
>
> It's even worse. There might be another sig constraint that is 
> perfectly happy. It might even be in another library. Your 
> function has no way to know that. Ergo, error messages are hard.
>
> With Rust a type declares to conform to a trait explicitly. 
> Error messages are easy.
>
> With D it seems we are reinventing traits, poorly. And all 
> because we wanted to avoid naming them?

https://github.com/atilaneves/concepts

Not the same, but works well enough for me.