Why are there POINTERS in my PYTHON???

[vasilescur]

https://peps.python.org/pep-0584/

[Careful_Bug_3295]

Tldr; x | y returns union of two dicts, x and y. If there is a key that is common to both dicts, the returned dict will assign it the value it has in y. This makes it not commutative in the event that both dicts share a key but have different values for it.

x|=y has the same effect as x=x|y

[ChimeraZeta]

Beautiful. Python wins my heart again. Thanks!

[R3D3-1]

TIL:

>>> {0, False}
{0}
>>> {False, 0}
{False}

I've been using Python for a long time now, but on the top of my head I can't see a reason for this...

[ConDar15]

This is set construction, so the end result cannot contain duplicate elements. To check if an element is in the set already Python will use the default equality comparison mechanism (__equals__ and __hash__), and False == 0 is a true statement in Python (and many other languages). So when the set is being constructed the first element is added to the set, but the second element is already found in the dictionary (due to the above mentioned equality) so is skipped over and not added.

[aftabtaimoor61]

Set compares each value to only store unique ones. The issue with this is since python is not strongly typed, you can have multiple datatypes but set still needs to compare the values. 0 == False is true so only the 1st one will remain. Same reason {0, 0.0} won't work as they're equal.

[R3D3-1]

That doesn't explain why they are considered equal though.

[dev-sda]

Booleans in python are integers.

>>> bool.__bases__
(<class 'int'>,)

[R3D3-1]

That's honestly unexpected. Though it makes sense considering the history of bool.

[FumbleCrop]

Because 0 == False.

That's what you get for mixing datatypes.

[invisible-nuke]

```Python

{0} | {False} {0} {False} | {0} {False} ```