Re: [Python-ideas] Adding "Typed" collections/iterators to Python

Nick Coghlan wrote:

What you seem to be asking for is a general purpose typed container factory along the following lines:

def typed_container(container_type, data_type):
    class TypedContainer(container_type):
        def __getattr__(self, attr):
            data_type_attr = getattribute(data_type, attr)
            if callable(data_type_attr):
                _result_type = type(self)
                def _broadcast(*args, **kwds):
                    _result_type(data_type_attr(x, *args, **kwds) for x in self)
                return _broadcast
            return data_type_attr
    return TypedContainer

Seems to me this would be better described as a "broadcasting container" than a "typed container". The only use it makes of the element type is to speed things up a bit by extracting bound methods. So the typed-ness is not an essential feature of its functionality, just something required to support an optimisation.

Extended to handle the various operator methods, this might be a useful thing to have around. In conjunction with array.array, it could provide a kind of "numpy lite" for when depending on full-blown numpy would seem like overkill.