Hey everyone! I'm having some trouble understanding the precedence of relational operators in Python. Specifically, I want to know the precedence levels of these operators:
1. (==, !=)
2. (>, =, <=)
The Python documentation mentions that all these operators have the same precedence and associativity, but I ran a little test and got unexpected results:
```python
print(5 < 5 == 5 <= 5)
```
According to the documentation, I thought this expression should return `True`. Here's my reasoning: if we evaluate it left to right, `5 < 5` gives `False` (or `0`), so it seems like the next part of the expression would be `0 == 5 <= 5`. Evaluating `0 == 5` also results in `False`, leaving us with `0 <= 5`, which is `True`. So why did I get `False` instead? Am I missing something? Thanks for any help!
3 Answers
It sounds like you're getting mixed up with how chaining works in Python. Even though these operators have the same precedence, `5 < 5 == 5 <= 5` is evaluated as if it's `5 < 5 and 5 == 5 and 5 <= 5`. To get the specific comparison you want, you need to use parentheses like this: `(5 < 5) == (5 <= 5).` That should clear things up!
Totally agree with you! It’s a common pitfall when learning Python. Glad you pointed that out!
Your expression is actually being interpreted like this: `print((5 < 5) == (5 <= 5))`. So while each side of the `==` has the same precedence, they are being treated as if they were in parentheses. This might seem strange, but it's just how Python handles these chained comparisons. I think it’s perfectly reasonable to be confused, though!
If you find yourself getting tangled up in operator precedence, consider restructuring how you're writing your comparisons. Using clear parentheses can make your intentions clear and avoid these sorts of surprises.
Exactly! Chaining is key here. Your step-by-step breakdown makes sense, but Python will evaluate the chained expressions together instead of separately as you're expecting.