`restricted` member variables

[bauss]

On Monday, 20 June 2022 at 11:57:23 UTC, Ola Fosheim Grøstad 
wrote:
> On Monday, 20 June 2022 at 11:28:45 UTC, Mike Parker wrote:
>> If my only invariant is the state of a single member variable, 
>> then I really only want it checked on the function(s) that 
>> actually write to it.
>
> Do you want all this complexity just to avoid using «hidden» 
> for marking fields class-private?
>
> Also, you need to be able to disable invariants, which adds 
> even more complexity.

"We have problem A and to solve it we have solution B, but 
solution B is too broad so solution C is proposed because it 
solves problem D which is caused by problem A, but we don't 
believe problem E is a real problem, so solving A using C we have 
created problem F which requires solution G."

Pretty much where we're at.