[Python-ideas] collections.Counter should implement __mul__, __rmul__

[Raymond Hettinger]

> On Apr 16, 2018, at 5:43 PM, Tim Peters <tim.peters at gmail.com> wrote:
> 
> BTW, if _`Counter * scalar` is added, we should think more about
> oddball cases.  While everyone knows what _they_ mean by "scalar",
> Python doesn't.

I've started working on an implementation and several choices arise:

1) Reject scalar with a TypeError if scalar is a Counter
2) Reject scalar with a TypeError if scalar is a Mapping
3) Reject scalar with a TypeError if scalar is a Collection
4) Reject scalar with a TypeError if scalar is Sized (has a __len__ method).

I lean toward rejecting all things Sized because _everyone_ knows that scalars aren't sized ;-)


Raymond