Clean Code

Author: Robert C. Martin (Uncle Bob)
Finished: November 20, 2024
Rating: ⭐⭐⭐⭐⭐
Genre: Technical

Summary

A handbook of agile software craftsmanship with practical advice on writing clean, maintainable code. The book covers everything from naming conventions to error handling, with lots of real-world examples.

Key Takeaways

1. Meaningful names matter - Names should reveal intent and be searchable
2. Functions should do one thing - Small, focused functions are easier to understand and test
3. Comments are often a code smell - Good code should be self-documenting
4. The Boy Scout Rule - Leave code cleaner than you found it
5. Error handling is important - Don’t return null, use exceptions properly
6. DRY principle - Don’t Repeat Yourself
7. Testing is crucial - Tests enable refactoring with confidence

Favorite Quotes

“Clean code is simple and direct. Clean code reads like well-written prose.”

“Indeed, the ratio of time spent reading versus writing is well over 10 to 1. We are constantly reading old code as part of the effort to write new code.”

“You should name a variable using the same care with which you name a first-born child.”

Personal Notes

This book fundamentally changed how I write code. Started applying:

• Meaningful variable names (no more x, temp, data)
• Breaking down large functions into smaller, focused ones
• Writing tests first (TDD approach)
• Regular refactoring sessions

The “leave it cleaner” mindset has become second nature now.

Code Examples Applied

# Before
def process(d):
    # ... 50 lines of code
    return r
 
# After
def calculate_discount(order):
    base_discount = _get_base_discount(order)
    loyalty_bonus = _calculate_loyalty_bonus(order.customer)
    return base_discount + loyalty_bonus

Related

• designing-data-intensive-applications - System-level clean architecture
• the-pragmatic-programmer - Broader software craftsmanship

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