On 5/2/20 4:44 AM, Robert M. Münch wrote:
On 2020-04-30 17:45:24 +0000, Steven Schveighoffer said:
You can use scope instead of auto, and it will then allocate the class
on the stack, and destroy it as Ben Jones said. There is danger there,
however, as it's very easy to store a class reference elsewhere, and
then you have a dangling pointer.
Ok. Can't this be combined with some "don't let the refrence escape my
function" feature of D?
I don't know. perhaps dip1000 helps here.
A safer thing to do is:
auto X = new MyClass();
scope(exit) destroy(X);
This runs the destructor and makes the class instance unusable, but does
not free the memory (so any remaining references, if used, will not
corrupt memory).
How would that help, because the class instance is now unusable anyway.
So I have it around like a zombie and others might think: "Hey you look
normal, let's get in contact" and then you are doomed...
The difference is that if you use it, you get an error and a crash. If
you clean up the memory, that memory could be reallocated to something
else with a completely different type, and now you have memory corruption.
-Steve
