On Saturday, 7 June 2014 at 21:18:39 UTC, Denis Martinez wrote:
Thanks for the answer Chris, you are correct.
I was expecting the closure to work similarly to Clang's
blocks, which apparently it does not. I guess that delegates
pass by copy, like structs do.
So far I have tried a variety of solutions.
1. As it is, passing the delegate as "ref" does not work,
because the compiler does not accept to do the implicit
conversion. It is the same logic as C++, here in C++11 I would
have passed by rvalue reference, a thing that does not appear
to exist in D.
2. Is it possible to make a delegate to be allocated on the
heap ?
I think of a syntax such as:
client.process_callback = new delegate int(jack_nframes_t
nframes) {
3. I have coded a workaround for the time being.
The function here copies the delegate into a heap-allocated
structure, and takes the interior pointer.
T *copyDelegate(T)(T dg) {
struct Tmp { T dg; }
auto x = new Tmp;
x.dg = dg;
return &x.dg;
}
I find this code to be rather inelegant, is there a better
solution?
&[dg][0] maybe
But you're storing dg in your (heap because class) object anyway,
as process_callback_. Just do that first and use
&process_callback_ instead of &dg. That also guarantees that
there's a pointer to it in D-land so that the GC doesn't collect
it.
