[idea] Mutable pointee/ RCString

[Iakh via Digitalmars-d]

Is it hard to make pointee data mutable?
E.g. if have:
------
struct RCString
{
     private char[] data;
     private @mutable int* counter;
}
------
So for optimiser (in case of immutable) this looks like
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struct RCString
{
     private char[] data;
     private @mutable void* counter; // pointer to garbage
}
------