[Cython] Automatic conversion with fixed-size C arrays

[Robert Bradshaw]

On Fri, Jul 18, 2014 at 12:44 PM, Robert Bradshaw <robertwb at gmail.com> wrote:
> On Fri, Jul 18, 2014 at 12:08 PM, Kurt Smith <kwmsmith at gmail.com> wrote:
>> On Wed, Jul 16, 2014 at 1:02 PM, Robert Bradshaw <robertwb at gmail.com> wrote:
>>>
>>>
>>> Yes, this'd be nice to have. One difficulty with arrays is that they
>>> can't be returned by value, and so the ordinary from_py_function
>>> mechanism (which gets called recursively) would need to be adapted.
>>> (Allowing to_py_function to be optinally be called by reference
>>> instead of by value could be nice as well from a performance
>>> standpoint.)
>>
>>
>> OK, thanks for the pointers.  I'll put some time on this over the weekend.
>> Should I just make a PR when things are ready to review, or should I put up
>> an issue first?
>
> I think this thread is sufficient; looking forward to a pull request.

Don't know if you had time to look at this yet, but another possible
hack would be to use the fact that struct { int x[N]; } is bit
compatible with int[N] and can be passed/assigned by value. E.g.

struct wrapped_array {
    int x[3];
};

int main(int argc, char** argv) {
    int src[3];
    int dest[3];
    *((struct wrapped_array *) &dest) = *((struct wrapped_array *) &src);
}

OTOH, it might make sense to simply add array members as a special
case in struct conversion.

- Robert