What does |= (ior) do in Python?

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Chapters
00:00 What Does |= (Ior) Do In Python?
00:12 Answer 1 Score 114
00:36 Answer 2 Score 10
00:50 Answer 3 Score 49
01:09 Answer 4 Score 53
01:16 Thank you

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Full question
https://stackoverflow.com/questions/3929...

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Content licensed under CC BY-SA
https://meta.stackexchange.com/help/lice...

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Tags
#python

#avk47

ANSWER 1

Score 114

In Python, and many other programming languages, | is the bitwise-OR operation. |= is to | as += is to +, i.e. a combination of operation and asignment.

So var |= value is short for var = var | value.

A common use case is to merge two sets:

>>> a = {1,2}; a |= {3,4}; print(a)
{1, 2, 3, 4}

ANSWER 2

Score 53

When used with sets it performs union operation.

ANSWER 3

Score 49

This is just an OR operation between the current variable and the other one. Being T=True and F=False, see the output graphically:

r	s	`r\|=s`
T	T	T
T	F	T
F	T	T
F	F	F

For example:

>>> r=True
>>> r|=False
>>> r
True
>>> r=False
>>> r|=False
>>> r
False
>>> r|=True
>>> r
True

ANSWER 4

Score 10

It performs a binary bitwise OR of the left-hand and right-hand sides of the assignment, then stores the result in the left-hand variable.

http://docs.python.org/reference/expressions.html#binary-bitwise-operations