"Walter Bright" <[email protected]> wrote in message
news:[email protected]...
> The issue is what if b is a property, returns a temporary object, and that
> temp's .c field is uselessly set to 3?
>
> It's a classic problem with properties that are implemented as functions.
>
> I don't see how C#'s special property syntax adds any value for dealing
> with this.
>
> One thought I had was to simply disallow the '.' to appear after a
> function style property.
Disallow it by default. IE.
a.b.c.d = 3;
If any of those return an rvalue / temporary then it should be an error to
assign to it.
However we should not disallow...
int i = a.b.c.d.e.f;
But we should also find a way to let the programmer tell the compiler if it
is ok for it to rewrite...
a.b.c = 3;
as
B tmp = a.b;
tmp.c = 3;
a.b = tmp;
perhaps an extra operator opSubAssign() Which tells the compiler it's ok
to rewrite the the assignment using temporrarys and reassignment.
class A
{
B _b;
void b.opAssign(ref B bbb) { _b = bbb; }
void b.opSubAssign(ref B bbb) { opAssign(bbb); }
}
Then the programmer could also write an specialized subassignment.
