Reuse C memory for D struct?

[Ali Çehreli]

On 11/21/2013 07:22 AM, Lemonfiend wrote:

 > I'm wondering if it's possible to have a struct in D which uses the same
 > pointer and memory as returned by the extern C function.
 > This would allow me to manipulate and use the C struct directly in D 
code.
 >
 > I'm not sure how to better explain this, hopefully the following
 > pseudocode clarifies my question
 >
 > struct Tree
 > {
 >      enum treeSize = 40;
 >
 >      ubyte[treeSize] _this;
 >
 >      this(int apples)
 >      {
 >          // use the C provided pointer somehow?
 >          // neither of the following seem to do the trick
 >          //this = *cppNew(apples);
 >          //_this = *cast(ubyte*)cppNew(apples)

If you instead maintain a slice of Apples and assuming that 'apples' is 
the number of apples, then you can use the following syntax

     Apple[] _this;

// ...

     _this = cppNew[0 .. apples];

I have some information about that syntax under the "Producing a slice 
from a pointer" section here:

   http://ddili.org/ders/d.en/pointers.html

One thing that is not mentioned in there is that you are still 
responsible for the Apples that are returned by the C library.

Ali