On Tuesday, 9 November 2021 at 02:43:55 UTC, jfondren wrote:
On Tuesday, 9 November 2021 at 02:41:18 UTC, jfondren wrote:
The expectation is probably that `f.move` set `f` to
`Foo.init`, but the docs say:
Posted too fast. Foo qualifies with its @disable:
```d
struct A { int x; }
struct B { int x; @disable this(this); }
unittest {
import core.lifetime : move;
auto a = A(5);
auto b = B(5);
a.move;
b.move;
assert(a == A(5));
assert(b == B(0));
}
```
Yes it should qualify so it should be cleaned out when moved.
When I change:
```D
auto ref unwrap(EX)(auto ref EX res) {
printf("unwrap()\n");
return res.get();
}
```
I get:
```
~this(0)
~this(0)
~this(0)
unwrap()
~this(42)
~this(0)
~this(42)
```
So the destructor isn't called from `gen()` -> there is
[NRVO](https://dlang.org/glossary.html#nrvo) in play.
Also `pragma(msg, __traits(isRef, res));` prints false in unwrap
in this case (which is expected), but how it gets there as a
value when it's not moved and instead copied even though it has
disabled copy constructor?
`isCopyable!(Value!Foo)` returns false as expected too.
