Another approach could be too simply pass the labelled indices in a dict as a third/fourth positional argument.  

So for indexing

b = arr[1, 2, a=3, b=4]

Instead of

__getitem__(self, (1, 2), a=3, b=4)

Just do

__getitem__(self, (1, 2), {'a': 3, 'b': 4})

On Mon, Aug 3, 2020, 16:46 Christopher Barker <> wrote:

Yes, that would be correct. However, the function could instead be defined as:

def __getitem__(self, index, /, **kwargs):

and then there'd be no conflict (as "self" and "index" must be passed
positionally). In effect, the naive spelling (which permits self and
index to be passed as keywords) would be a subtle bug that could
easily be corrected.

sure, but it would be a bug in a LOT of existing code!

I wonder, if this were to be introduced, if the interpreter could have a special case that would call __getitem__ in a special way to avoid this bug in old code.


Christopher Barker, PhD

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