Why the @ in @safe? & UDAs

[Dicebot]

On Thursday, 7 November 2013 at 19:21:49 UTC, Michael wrote:
> So, @ for UDA only?
> +1

First, there is no point in "+1", it will never be in D as it is 
major breaking change :) Just some interesting experiment in 
similar but much younger language.

Second, no, it is not "@ for UDA only". It is "@ for everything 
that does not impact ABI, including all UDA and some built-in 
stuff like @public/@private/@package".