Hello, checkiomates🐱‍👤!

This week's digest explores the depths of code quality, from detecting performance regressions with Big-O tests to mastering recursive structural pattern matching. We also recap the year with a Django quiz and challenge you to calculate the factorial of a number.

💡TIP

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🏁 MISSION

Number With Exclamation by freeman_lex -

This function should take a non-negative integer as an input and return the factorial of that number.

factorial(1) == 1
factorial(5) == 120
factorial(10) == 3628800

📖 ARTICLES

Unit testing your code’s performance, part 1: Big-O scaling -

Testing your code is important, but not just for correctness also for performance. One approach is to check performance degradation as data sizes go up, also known as Big-O scaling.

Recursive structural pattern matching -

Learn how to use structural pattern matching (the match statement) to work recursively through tree-like structures.

Django Quiz 2025 -

The December quiz is an annual tradition at our meetup, a way of making this final event of the year more relaxed and giving away some nice prizes.

👩‍💻CODE SHOT

What do you think the following code does?

from itertools import groupby


def checkio(a):
    for _, cons in groupby(a):
        yield sum(cons)

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