Jarrett Billingsley wrote:
The issue is that the compiler accepts
no-effect modifications of temporary values as valid statements.
There is no setter being invoked here, nor should there be.
Or should there? In the face of a value type, should the compiler
rewrite this code as
auto t = a.b();
t.c = 3;
a.b = t;
? The last line of the rewrite is unnecessary if a.b() returns a
reference type or a byref struct. But is this what people would
expect to happen?
I think the compiler should only rewrite the code (as above) if a.b()
returns a struct, by value. The compiler can figure that out easily
enough. Depending on the return types of all the different properties in
a.b.c.d.e.f = 3, there might be a few ref types and a few value types
returned. Each of those subexpressions would be rewritten with the
appropriate semantics.
--benji
