[Cython] planning for 0.17

[mark florisson]

On 27 June 2012 13:48, Stefan Behnel <stefan_ml at behnel.de> wrote:
> mark florisson, 27.06.2012 14:17:
>> On 27 June 2012 12:59, Stefan Behnel wrote:
>>> mark florisson, 27.06.2012 11:54:
>>>> I can't test it right now, but I don't understand the following in the
>>>> release notes (regarding array.array): "Note that only the buffer
>>>> syntax is supported for these arrays. To use memoryviews with them,
>>>> use the buffer syntax to unpack the buffer first.". Why is that, it
>>>> implements __getbuffer__ right? So it shouldn't matter whether you use
>>>> memoryviews or buffer syntax, both use __Pyx_GetBuffer().
>>>
>>> The problem is that arrayarray.pxd is only used when the exporter is typed.
>>> This means that you can't do this:
>>>
>>>    def func(int[:] arr): pass
>>>
>>>    func(array.array('i', [1,2,3]))
>>
>> That works for me, as long and array is cimported from cpython (as
>> 'array' or some other name). It will patch __Pyx_GetBuffer with a
>> typecheck and a call to its __getbuffer__ method.
>
> Hmm, interesting. I keep learning. I'll add tests for that.
>
> For the memoryview_type and array_type checks, wouldn't a type identity
> test be enough instead of a PyObject_TypeCheck() ?
>
> Stefan
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Well, you want it to work for subclasses as well. I think the only
thing that doesn't work (pre-2.6), is overriding __getbuffer__ in a
subclass outside of the module or pxd. For memoryviews, since each
module has a different memoryview type, I inject a capsule in tp_dict,
which __Pyx_GetBuffer checks for (it's called __pyx_getbuffer and
__pyx_releasebuffer).