DIP77 - Fix unsafe RC pass by 'ref'

[bearophile via Digitalmars-d]

Marc Schütz:

> You have to keep in mind that this is opt-in; it only applies 
> to `scope` variables. I would agree that as a default, it 
> wouldn't fit D at all. I think that, for all its usefulness, 
> it'd be a tad too limiting for my taste if I were forced to use 
> it everywhere.

I think D Zen asks for safety on default and opt-out on request.

See also "@safe by default":
https://issues.dlang.org/show_bug.cgi?id=13838

Bye,
bearophile