In Python, 0 == (1 or 0), returns False. Why doesn't it return True?

user_15133080 0
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I'm trying to see if a function returns an integer who's value should be either a 1 or 0.

0 == (1 or 0)

0 is equal to 1 or 0, this sounds like it should be true, but it's not.

Why? And how to do what I'm looking to do correctly?

boolean-logic equals python
3 Answers

0 == (1 or 0) is parsed as this tree:

  ==
 /  \
0    or
    /  \
   1    0

1 or 0 results in 1, because or returns the first truthy value of the two operands (and 1 is truthy).

Afterwards, we're left with 0 == 1, which is obviously False.

What you want to do, is check whether 0 is one of those values which you can do through a sequence check: 0 in (0, 1)

user_10162160

1 or 0 evaluates to 1, and since 0 is not equal to 1, the expression is false.

I suspect what you are trying to do is something like 0 == 0 or 1 == 0

user_24919000

You are using the brackets. Which means you are forcing precedence on it. so python will first evaluate the expression 1 or 0 which is 1. and then it will evaluate the next part, 0 == 1 which is false.

user_103507550
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