How Does Logical Operator Precedence Work in Python?

Logical Operator Precedence in Python

When dealing with logical operators in programming languages, understanding their precedence and order of operations is crucial. In Python, the operators NOT, AND, and OR follow a specific hierarchy that governs the order in which they evaluate expressions.

Precedence Order:

Contrary to the precedence sequence in C and C (NOT > AND > OR), Python has its own unique order:

1. NOT
2. AND
3. OR

From highest to lowest precedence, NOT evaluates first, followed by AND, and then OR. This means that NOT operations take precedence over both AND and OR, and AND operations take precedence over OR.

Example:

Consider the following Python expression:

result = not a and b or c

According to the precedence order, the expression will be evaluated as follows:

1. a is checked for truthiness.
2. If a is False, not a is True. Otherwise, it's False.
3. If the result of not a is True, and b evaluates to b. Otherwise, it's False.
4. If the result of and b is True, the entire expression evaluates to True. Otherwise, the result of or c is evaluated.
5. c is checked for truthiness.
6. If c is True, the entire expression evaluates to True. Otherwise, it's False.

Complete Precedence Table:

For a comprehensive list of operator precedence in Python, refer to the following table:

Precedence

Operators

0

Assignment (=)

1

Lambda functions (lambda)

2

Conditional expression (if-else)

Precedence	Operators
0	Assignment (=)
1	Lambda functions (lambda)
2	Conditional expression (if-else)
3	Logical OR (or)
4	Logical AND (and)
5	Logical NOT (not)
6	Comparison operators (, >=, !=, ==)
7	Bitwise OR (	)
8	Bitwise XOR (^), Bitwise AND (&)
9	Shift operators (>)
10	Addition ( ), Subtraction (-)
11	Multiplication (*), Division (/), Floor division (//), Modulo (%)
12	Unary plus ( ), Unary minus (-), Bitwise NOT (~)
13	Exponentiation (**)
14	Coroutine creation (async with)
15	Indexing and slicing ([...], [...]), Function calls, Attribute access
16	Parentheses, Square brackets, Braces, Set literals

3

Logical OR (or)

4

Logical AND (and)

5

Logical NOT (not)

6

Comparison operators (, >=, !=, ==)

7

Bitwise OR (

)

8

Bitwise XOR (^), Bitwise AND (&)

9

Shift operators (>)

10

Addition ( ), Subtraction (-)

11

Multiplication (*), Division (/), Floor division (//), Modulo (%)

12

Unary plus ( ), Unary minus (-), Bitwise NOT (~)

13

Exponentiation (**)

14

Coroutine creation (async with)

15

Indexing and slicing ([...], [...]), Function calls, Attribute access

16

Parentheses, Square brackets, Braces, Set literals

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