Flagging special conditions on return from a function call

[Denis]

On Tuesday, 23 June 2020 at 21:34:25 UTC, Paul Backus wrote:

> If you're open to using Dub packages [...]

Because this is going to be used in almost every program I write, 
I need to eliminate outside dependencies as an option. 
Nonetheless, thanks for this suggestion.

> [2] 
> https://pbackus.github.io/blog/beating-stdvisit-without-really-trying.html

I did read your blog post: that's an impressive result. Good to 
know that well-written D code can be competitive with C.

Denis