Talk:Property Discussion Wrap-up
ref returns and taking the address
ref T prop()
The current behavior without @property enforcement is that the setter function is called if there is one, else the reference to the return type is used.
prop = 4; // calls setter
If there is a setter property, but you want to bypass the setter, then
prop() = 4; // direct access to T ref
To limit @property ref retuns is a very harsh restriction to impose.
A solution is to allow
ref const(T) prop()
prop = 4; // calls setter
prop() = 4; // compile error
*(prop()) = 4; // compile error
What if you take the address of prop?
&prop returns the getter function address, but I'm not sure how to get the setter prop address.
&prop() returns the ref storage address. If return is const, you should be OK unless you do unsafe operations.
With @property enforcement, if we try to emulate storage addresses, then we'll have to disallow taking the address but that will significantly defeat the purpose of variable emulation. We can do something like this:
&prop returns the address of the setter function if there is one, else compiler error.
*(&prop) = 5; // calls the setter
Is the complexity of true variable emulation justified, or do we implement only partial variable emulation? But is enforcing variable emulation justified if we're to only partially implement? I would say we must either do full variable emulation, or not bother with it and treat the properties as regular functions.
