What have you done with UDAs?

[Random D-user via Digitalmars-d]

On Monday, 22 June 2015 at 19:09:40 UTC, weaselcat wrote:
> I never seem to use them for anything, has anyone else done 
> anything interesting with them?

What a cool thread.
This is very valuable info for new(ish) d users.

It's often the case for language features that they are just 
branded cool. But that's just a statement (and you go 'uhm, 
ok.'). What people usually need is some kind of proof or 
demonstration why they are useful and how to solve problems with 
them (which you can usually only get through experience).

Wouldn't it be great if there was a wiki page of cool d-features 
where each feature would have a list like this showcasing what 
people have done with it?

You could then just point people to this wiki page to get a 
practical view of why d is great.