On Friday, 23 July 2021 at 20:24:02 UTC, Jim wrote:
Hello,
I've been playing with D and trying to understand how to work
with @nogc. I must be doing something wrong, because even
though I tagged the destructor for my class `@nogc`, I'm
getting the following error: `.\min.d(27): Error: "@nogc"
function "D main" cannot call non-@nogc function
"object.destroy!(true, TestClass).destroy`
```D
import std.stdio : printf;
import core.lifetime : emplace;
import core.stdc.stdlib : malloc, free;
class TestClass {
int x;
this(int x) @nogc {
printf("TestClass's constructor called\n");
this.x = x;
}
~this() @nogc {
printf("TestClass's destructor called\n");
}
}
@nogc void
main() {
auto size = __traits(classInstanceSize, TestClass);
auto memory = malloc(size)[0..size];
TestClass x = emplace!(TestClass)(memory, 1);
printf("TestClass.x = %d\n", x.x);
destroy(x);
free(cast(void*)x);
}
```
What is the problem here? Should I not call `destroy`? If so,
what should I call instead?
You can call function like `destroy` with right attributes for
class variable if you known exact type of the class (no base
class referece or interface):
https://github.com/atilaneves/automem/blob/master/source/automem/utils.d
