On Friday, 2 September 2016 at 17:33:22 UTC, Steven Schveighoffer
wrote:
On 9/2/16 1:18 PM, Q. Schroll wrote:
When overloading assignment, I've been taught in my C++ course
to return
a reference to the lvalue being assigned to. This is easily
possible in
D, but in Phobos it is used rarely and in Ali Çehreli's Book
it is
neither taught to do so.
Sure, you can do this.
Is there any reason to it? To me it seems very obvious to do
it like in
C++.
I can imagine a reason is to avoid issues with lifetime. It's
dangerous to return this as a reference in most cases, because
this is implicitly passed by reference even for rvalues.
However, for opAssign, you generally are sure you don't have an
rvalue.
Interestingly the compiler does not allow rvalue = expr but it
does however allow rvalue.opAssign(expr).
In any case, there's nothing wrong with it technically, it
should work.
-Steve
There is no possibility to enforce some method is only available
for lvalue this?
