Serhiy Storchaka <[email protected]> added the comment:
It is a difference with typing.Union which can cause confusion. If the union
type is like a tuple and we leave a 1-type union, why do we bother with
deduplication? Why int | str | int is collapsed into int | str?
Also it complicates the comparison implementation and produces surprising
exceptions:
>>> int | str == {}
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: unhashable type: 'dict'
Also it breaks one of fundamental properties -- equal objects should have equal
hashes.
>>> (int | int) == int
True
>>> hash(int | int) == hash(int)
False
----------
_______________________________________
Python tracker <[email protected]>
<https://bugs.python.org/issue44636>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
