//Everything defined here is @safe pure nothrow attributes @system
You can do that now with colons: @system: stuff....The problem is there's no way to turn some of them off. For @safe, there's @system, but there's no "throws" for nothrow, no "impure", no "virtual", etc.
This btw is another trivially easy addition that's been talked about for a while that should just be done for the next release.