Sorry I forgot to add the URL:

On Fri, 22 May 2020 at 20:25, Andrey Cizov <> wrote:

> I have developed a library to introduce tagged unions to python that uses
> dataclasses to define disjoint members of the tagged union (by defining
> them as Optional fields). With some additional validation I make sure that
> only one of the fields is not None.
> I find that it also fits well with the existing analysis tools and IDEs
> (e.g. PyCharm) and doesn’t require any additional work in order to be
> supported.
> I would like to see some criticism and whether that could potentially be a
> good candidate for python standard library in the future.
> --
> Andrey Cizov
Andrey Cizov
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