Vision for the D language - stabilizing complexity?

[Andrei Alexandrescu via Digitalmars-d]

On 07/12/2016 02:45 PM, Jacob Carlborg wrote:
> On 2016-07-12 07:33, Andrei Alexandrescu wrote:
>
>> The solution (very ingenious, due to dicebot) in fact does not quite
>> cast immutability away. Starting from a possibly immutable pointer, it
>> subtracts an offset from it. At that point the memory is not tracked by
>> the type system, but known to the allocator to contain metadata
>> associated with the pointer that had been allocated with it. After the
>> subtraction, the cast exposes the data which is mutable without
>> violating the immutability of the object proper. As I said, it's quite
>> an ingenious solution.
>
> What if the immutable data is stored in ROM [1]? I assume it's not
> possible to have an offset to a completely different memory storage.
>
> Not sure if this is important enough to care about.
>
> [1] http://dlang.org/const-faq.html#invariant

The assumption is that the memory comes from that allocator. -- Andrei