Is `left, right = right, left` the Standard Way to Swap Variables in Python?

Swapping Variables in Python: The Standard Approach

In Python, there are various techniques for swapping two variables. Among them, there's a particular syntax that has gained widespread use:

left, right = right, left

So, is this the standard method for swapping variables? Or are there any other established conventions?

The Magic of Python's Evaluation Order

Python follows a specific evaluation order during assignment, with the right-hand side being evaluated before the left-hand side. This unique behavior plays a crucial role in the swapping process:

• The right-hand side (in this case, right, left) is first evaluated. A temporary tuple is created, holding the objects formerly assigned to b and a, respectively.
• The left-hand side (i.e., left, right) is then evaluated, and the tuple is assigned to these variables.
• The unpacking process ensures that the first element of the tuple is assigned to a, while the second element is assigned to b.

This sequence of events effectively swaps the objects assigned to a and b.

The Answer: A Standardized Approach

Therefore, the answer to your question is a resounding yes. The syntax you provided (left, right = right, left) is indeed the standardized way to swap variable values in Python. It leverages the language's evaluation order to perform the swap in a simple and efficient manner.

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