...build of it by default.

You can opt into using a switch to use a...

...a DRuntime function from my usercode) to opt into displaying such a message box for...

...will be for an opt-out syntax rather than an opt-in one.

[ada-dip...

...is not good that you have to opt into doing the more restrictive thing because...

...tests in the same file, it is good that you have to explicitly opt in.

...each of those are specialized enough to opt-in to whatever strategy is appropriate.

But...

...s an addition to the language, fully opt-in, it doesn't interact with pretty...

...to me. But this has to be opt-in, based on data structures, and interoperate...

...there could later be private(this) to opt-in to accessing those fields. That is...

...create a way to make it completely opt-in without breaking existing code, then that...