Re: Possible @property compromise

[TommiT]

On Wednesday, 30 January 2013 at 21:07:56 UTC, TommiT wrote:
The problem is that genie is out of the bottle once you have 
committed yourself to an interface where there is a public 
member variable. And you can't put the genie back in the bottle 
any more. This means that your interface can't add any 
encapsulation over this public member variable afterwards 
without changing the interface.

A bit more code, a bit less metaphors:

struct S
{
    T data;
}

// end-user code:

S s;
*&s.data = 42;

End-user thus by-passes any encapsulation that could be possible 
added over S.data field later on, like the following:

struct S
{
    private T _data;

    @property ref T data() { return _data; }

    @property ref T data(int v)
    {
        assert(v != 42);
        _data = v;
        return _data;
    }
}