opOpAssign on object properties

[collerblade via Digitalmars-d-learn]

On Sunday, 8 January 2017 at 10:03:50 UTC, Ivan Kazmenko wrote:
> On Sunday, 8 January 2017 at 09:22:12 UTC, collerblade wrote:
>> [...]
>
> 1. If you want the member variable to change, naturally, you 
> should provide a getter property which returns a reference to 
> that variable:
>
> [...]

yes i tried the reference return, but the problem is, that the 
setter does NOT gets called, no matter what the result type of 
the opOpAssign method is.
I want to detect changes, but this way i still not able.

A a = new A;

a.location+=Point(1,1); //the private value changes, but the 
setter does not get called