ACLs for variables - lock / unlock idea

[Atila Neves]

On Friday, 29 September 2017 at 11:12:32 UTC, Cecil Ward wrote:
> An idea, I’d be interested to hear if this might be at all 
> useful to anyone -
>
> If and only if a variable is declared as modifiable (neither 
> immutable nor const), would it possibly be useful to be able to 
> have a kind of scope const on/off switch to either impose const 
> within a block, and/or the converse, that is to impose const as 
> the default everywhere starting say from an initial directive 
> straight after the (modifiable) declaration, while being able 
> to flick the const protection switch off within a block?

auto modifiable = foo();
{
     const nonModifiable = modifiable;
     //...
}

Or refactor the scope into a function accepting your modifiable 
variable as const.

Atila