2013/5/17 Don Clugston <dclugston@gmail.com>
> What do you find unacceptable/inconvenient in "-transition=XXX" approach?

Because 100% of existing cases must be changed.

This isn't even like static variables becoming shared by default, where some of the cases needed to change to __gshared but the rest were OK with becoming shared.
Every existing usage becomes a bug. There are no exceptions.

In 2.063, some non-mutable field access were already changed to error.

struct S {
    immutable int x = 10;
}
enum y = S.x;  // 2.063 will cause "need 'this' for x" error.

At least in such cases, these are not silent breaking of existing code.

Kenji Hara