request switch statement with common block

[bearophile]

monarch_dodra:

> Awesome. I'll have to introduce std.traits to this new syntax.

That DIP is not updated to what was actually implemented by 
Kenji. There is support for both enum and alias.

But after a good look at my code base I have not found many 
places where the new syntax is useful. In my opinion it's handy, 
but it's not a large win. And I still haven't seen any kind of 
such statistics done on Phobos before the implementation of this 
feature pair.

People have asked for a more general syntax, useful in more 
templates, but I have not seen a serious answer that explains why 
DIP42 is a good idea, while the other more general proposal (of a 
Self or something to be used in templates to make them more DRY) 
is is worse.

Bye,
bearophile