On Friday, 30 June 2023 at 16:14:48 UTC, jmh530 wrote:
On Thursday, 29 June 2023 at 23:51:44 UTC, bachmeier wrote:
[snip]
Glad you're continuing to do work on this front. There's a lot
of great material explaining things, which is always good.
It would be cool to have another version of the link below for
using a mir Slice with R.
https://bachmeil.github.io/betterr/setvar.html
I was wrong. They added custom allocators a while back, but
didn't tell anyone.
Actually, what I said before is technically correct. The SEXP
struct itself still has to be allocated by R and managed by the R
garbage collector. It's just that you can use a custom allocator
to send a pointer to the data you've allocated, and once R is
done with the data, it'll call the function you've provide to
free the memory before destroying the SEXP struct that wraps it.
I uploaded [an example
here](https://github.com/bachmeil/betterr/blob/main/testing/testalloc.d).
It's still a bit hackish because you need to adjust the pointer
for a header R inserts when it allocates arrays. Adjusting by
10*double.sizeof works in this example, but "my test didn't
segfault" doesn't exactly inspire confidence. Once I am
comfortable with this solution, I'll do a new release of betterr.
This'll be kind of a big deal if it works. For instance, if you
want to use a database interface and D doesn't have one, you can
use R's interface to that database without having R manage your
project's memory. You could use any of the available R interfaces
(databases, machine learning libraries, Qt, etc.)
