On Tue, Aug 25, 2020 at 2:26 AM Christopher Barker <python...@gmail.com>
wrote:

> As for "why not" not being a motivator -- I agree, I posted it that easy
> because this conversation has brought up a number of examples where slice
> syntax is nice to use. And David Mertz pointed out, both numpy and pandas
> have a utility to make easier slices -- yes, that's an argument for why you
> don't need them, but it's also an argument for why there IS a need for
> slice objects outside of the square brackets, and if we need slice objects,
> then slice syntax is nice.
>

Pandas is kinda special though.  It semi-abuses Python syntax in quite a
few places.  For example, here is an example from the Pandas docs:

>>> idx = pd.IndexSlice>>> dfmi.loc[idx[:, 'B0':'B1'], :]

There is a hierarchical index (MultiIndex) where we want to put slices as
some of the "dimensions" of slice items.  It definitely makes sense in the
Pandas world, but I have never once encountered anywhere I would want
"stand-alone" slice objects outside of Pandas.  I know NumPy includes the
same convenience, but it's not even coming to me immediately in what
context you would want that in NumPy.

Personally, I like the single letter `I` even more than the `idx` name in
the example.  But in general, having to use a somewhat special object to do
something that really is rare and special doesn't feel like a big burden.
Moreover, as others have noted, in dictionaries and elsewhere, allowing
slices as generic expressions allows for very confusing looking code (I
won't say it's *definitely* ambiguous, but certainly hard for humans to
make sense of, even if the parser could).

-- 
The dead increasingly dominate and strangle both the living and the
not-yet born.  Vampiric capital and undead corporate persons abuse
the lives and control the thoughts of homo faber. Ideas, once born,
become abortifacients against new conceptions.
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