It works better if it is part of the language from the start. Having said that, we can probably implement it using only existing keywords. Maybe: import java.l

It works better if it is part of the language from the start. Having said that, we can probably implement it using only existing keywords. Maybe: import java.lang.extensions.assert. (I assume Java has some reserved part of the package namespace they can use for this purpose. Even if they don't, it shouldn't be difficult to find a package name that hasn't been used by anyone yet)