How do you deal with scoped allocations?

[Dmitry Olshansky]

08-Dec-2013 02:32, Namespace пишет:
> Since my last thread doesn't get much attention I like to ask here: How
> did you deal with temporary memory? Let's assume that the size is only
> known at runtime.
> I have this situation e.g. in Dgame in the capture method: I get the
> pixel data from my Window with glReadPixel but it is reversed. So I have
> to reverse it again, but I still need at least temporary memory for one
> pixel-line which stores the currently swapped pixels. So how would you
> solve such a situation?
>
> Since D doesn't offer VLA's and alloca is broken (besides the ugly syntax),
> I use a scoped wrapper (since scope doesn't do the job):
>
> ----
> struct scoped(A : T[], T) {
>      T[] arr;
>
>      alias arr this;
>
>      this(T[] arr) {
>          this.arr = arr;
>
>          writefln("Get %d %s's (ptr = %x)", arr.length, T.stringof,
> arr.ptr);
>      }
>
>      ~this() {
>          GC.free(this.arr.ptr);
>          this.arr = null;
>          GC.minimize();

This is slow. Just use malloc & free, why touch GC at all?
>      }
> }
>
> void main() {
>      // need temp memory
>      scoped!(int[]) arr = new int[n];
> }
> ----
>
> And what do you use?


-- 
Dmitry Olshansky