Article: Why Const Sucks

[Dukc]

On Monday, 5 March 2018 at 10:57:35 UTC, Jonathan M Davis wrote 
(in the article):
> The problem is that the entire object must be fully initialized 
> before
> the body of the postblit constructor is run. That means that 
> any member
> variables which are const or immutable are stuck at whatever 
> they were in
> the original object, because it would violate the type system 
> to mutate them. And if an object is const or immutable, then 
> that's all of the members.

I think we have a misunderstanding here. According to that, this 
would not compile (imports left out):

struct placeAtWorldMap
{   char[] title;
     int[2] coordsMicroDeg;

     this(this)
     {   title = title.dup;
     }
}
void main()
{   char[] title = "London bridge".dup;
     const place = placeAtWorldMap(title, [51_508_038, -87_693]);
     const samePlace = place;
     "falling down ".copy(title);
     place.title.writeln; // falling down
     samePlace.title.writeln; // London bridge
     readln;
}

...but it compiles and correctly runs, and I'm happy about that.