Swap Variables in One Line: Python’s Neat Trick to Simplify Your Code

Have you ever found yourself writing extra lines of code just to swap two variables? Maybe you’ve used a temporary variable like this:

python temp = a a = b b = temp

If so, you’ll love this Python trick. With just one line, you can swap variables effortlessly:

python a, b = b, a

No temporary variable, no extra steps—just clean, efficient code. This simple yet powerful feature is one of Python’s many elegant shortcuts that make coding faster and more enjoyable.

In this article, we’ll explore:

• How this one-liner works under the hood
• Why it’s better than the traditional swap method
• Other handy Python one-liners to boost your productivity

🔄 How Does a, b = b, a Work?

At first glance, a, b = b, a might seem like magic. But Python makes it possible through tuple unpacking. Here’s what happens:

1. Python evaluates the right side first, creating a temporary tuple (b, a).
2. It then unpacks the tuple into the variables on the left side (a and b).

So, internally, it’s similar to:

python tmp = (b, a) a, b = tmp

But since Python handles this automatically, we don’t need to write the extra steps.

💡 Why Is This Better Than Using a Temporary Variable?

✅ Cleaner Code – Fewer lines = easier readability.
✅ Faster Execution – No extra variable assignment means slightly better performance.
✅ Less Room for Errors – No risk of misplacing or forgetting the temp variable.

🚀 Beyond Swapping: Other Python One-Liners You’ll Love

Python is full of shortcuts that make coding faster. Here are a few more favorites:

1️⃣ Reverse a List in Place

Instead of writing a loop, just use:

python my_list = [1, 2, 3] my_list.reverse() # or my_list[::-1] for a new reversed copy

2️⃣ Check if All Elements Meet a Condition

Need to verify if all items in a list satisfy a rule?

python all(x > 0 for x in [1, 2, 3]) # Returns True

3️⃣ Merge Two Dictionaries (Python 3.5+)

Combine dictionaries with a single line:

python dict1 = {'a': 1} dict2 = {'b': 2} merged = {**dict1, **dict2} # {'a': 1, 'b': 2}

4️⃣ Find the Most Frequent Element in a List

No need for manual counting—use max with key:

python numbers = [1, 2, 2, 3, 3, 3] most_frequent = max(set(numbers), key=numbers.count) # Returns 3

🤔 When Should You Avoid One-Liners?

While one-liners are great, they aren’t always the best choice:

❌ If readability suffers – If a one-liner makes the code harder to understand, a multi-line approach may be better.
❌ For complex logic – Some operations need clarity over brevity.
❌ In team projects – If your teammates aren’t familiar with the syntax, it might cause confusion.

🎯 Final Thoughts

Python’s a, b = b, a is a perfect example of how the language prioritizes simplicity and efficiency. Whether you’re swapping variables, reversing lists, or merging dictionaries, one-liners can save time and make your code more elegant.

What’s your favorite Python one-liner? Drop it in the comments—let’s see who knows the coolest shortcut! 👇

Happy coding! 🚀