Harald Husum

Would love to see this merged.

@vdonato Sorry for leaving this hanging. It's been a busy week. I've updated `st.slider` so that it still returns `Any` for now. That should remove the need for casting the...

@failure-to-thrive describes the intended use. To ease the use of this metric one could possibly implement some opportunistic flattening where this does not lead to ambiguity, like in this case....

Wouldn't it be better to just implement support for strings and datetimes? I don't see a good reason to not support these data types in a parcoords plot.

I don't know much javascript, but I did play around with adapting `plotly.express` (the python API) to deal with these data types. That wasn't too hard, but involved the not-so-graceful...

I have yet another use case for `Not`. Making the typing for `Mapping.get` more accurate. If we had `Not`, we could express it like so: ```py class Mapping(Collection[_KT], Generic[_KT, _VT_co]):...

> In addition to the many benefits for styling (mentioned here and in #4975), this is IMO quite handy for automated tests. This! Trying to write good end-to-end tests for...

This right here! Came across [this post](https://lexi-lambda.github.io/blog/2019/11/05/parse-don-t-validate/), and wanted to see if I could do something similar using python`s types, without having to subclass, or similar.

@JelleZijlstra I see your point. Maybe this shouldn't be allowed for a mutable container. But it still makes sense for, say a `str`, or what do you think? EDIT: Realizing...

> An immutable container is easier, but it would still be a huge project. If you do `str.strip()`, does that give you another nonempty string? This is not too different...