Does Operator Precedence Matter When Comparing Membership and Equality in Python?

Understanding Operator Precedence of 'in' and Comparison Operators in Python

When working with operators in Python, it's important to understand their precedence to avoid unexpected results. The 'in' operator checks for membership, while comparison operators (e.g., ==) check equality.

Consider the following comparisons:

<code class="python">'1' in '11'  # True
('1' in '11') == True  # True</code>

These comparisons produce True, indicating '1' is a member of '11'. However, the order of parentheses can significantly impact the outcome. For instance:

<code class="python">'1' in ('11' == True)  # TypeError</code>

This raises a TypeError because '1' cannot be in a boolean value ('11' == True) since booleans are not iterable.

To obtain False without parentheses, we can use the fact that 'in' and comparison operators have equal precedence by default:

<code class="python">'1' in '11' == True  # False</code>

In this expression, the 'in' operator is not chained with '== True'. Instead, it is evaluated first, returning True. Then, the result (True) is compared to True using the '==' operator, which results in False.

The above is the detailed content of Does Operator Precedence Matter When Comparing Membership and Equality in Python?. For more information, please follow other related articles on the PHP Chinese website!