On Wednesday, 21 July 2021 at 08:28:22 UTC, Mike Parker wrote:
On Wednesday, 21 July 2021 at 08:11:06 UTC, vit wrote:
Is it possible to call all shared static ctors in betterC?
```d
//-betterC
static immutable int i;
shared static this(){
i = 42;
}
extern(C) void main(){
assert(i != 42);
}
```
These rely on DRuntime, which is not linked in betterC mode.
You'll need to use the `crt_constructor` and `crt_destructor`
pragmas:
https://dlang.org/spec/pragma.html#crtctor
Apply them to any `extern(C) function for static ctor/dtor
behavior.
Thanks, it works, but now I have different problem.
I need call static method for all instantions of template struct
from `crt_constructor`.
Is there way to iterate over all instantions of template?
I need this to work but for all instantions of Foo, not only for
Foo!1 a Foo!2
https://run.dlang.io/is/FNqHWh :
```d
pragma(crt_constructor)
extern(C)void shared_static_this(){
Foo!1.vtable_init();
Foo!2.vtable_init();
//Foo!3.vtable_init();
}
extern(C) void main(){
auto foo1 = Foo!1(null);
auto foo2 = Foo!2(null);
auto foo3 = Foo!3(null);
Base* b1 = &foo1.base;
Base* b2 = &foo2.base;
Base* b3 = &foo3.base;
assert(b1.getId() == 1);
assert(b2.getId() == 2);
//assert(b3.getId() == 3); //vtable is not initialized
}
struct Vtable{
size_t offset;
size_t function(void* ) getId;
}
struct Base{
immutable Vtable* vptr;
this(immutable Vtable* vptr){
assert(vptr !is null);
this.vptr = vptr;
}
size_t getId(){
return vptr.getId((cast(void*)&this) - vptr.offset);
}
}
struct Foo(size_t id){
static immutable Vtable vtable;
Base base;
this(typeof(null) nil){
this.base = Base(&vtable);
}
static size_t virtual_getId(Foo* foo){
return id;
}
static void vtable_init(){
Vtable* vtable = cast(Vtable*)&vtable;
vtable.offset = base.offsetof;
vtable.getId = cast(typeof(Vtable.getId))&virtual_getId;
}
}
```
