On 11/23/17 12:57 AM, Nicholas Wilson wrote:
On Wednesday, 22 November 2017 at 15:07:08 UTC, Tim Hsu wrote:
I am a C++ game developer and I want to give it a try.
It seems "this" in Dlang is a reference instead of pointer.
How can I pass it as void *?
void foo(void *);
class Pizza {
public:
this() {
Pizza newone = this;
// works but newone is actually not this pizza.
foo(&newone);
// this does not work..
foo(this);
}
}
void main() {
Pizza pizza = new Pizza();
// this works...
foo(&pizza);
}
Note that all the examples and advice in this thread apply to _classes_,
not to structs.
A further way to look at it, a class is really not the same as what you
normally think as references (either ref parameter in D or & type
constructor in C++). It's really simply a pointer that cannot be used
with pointer math.
ref parameters:
* cannot be rebound (you can't make it point at another value)
* don't act any differently than auto-storage variables. Making a copy
does not make a new reference, but rather copies the whole thing.
class references:
* CAN be rebound.
* copying to another variable does not copy the data, ever (you can't
make a variable that represents the class data)
-Steve
