Practical Zen of Python
- 1. PRACTICAL ZEN OF PYTHON @FEMMERLING - ID-PYTHON JOGJA NOV 2016
- 2. PRACTICAL ZEN OF PYTHON A BIT ABOUT ME ▸Fauzan Erich Emmerling ▸Married, 3 kids all of which will grow up learning python :) ▸Using python since 2010 and still learning more ▸Lives in Jogja after 14 years struggling with massive traffic jam in Jakarta ▸VP of Engineering at Prism, yes we’re hiring! ▸@femmerling on twitter @fauzan on python-id slack fauzan@python.or.id fauzan@prismapp.io
- 3. THE ZEN OF PYTHON IS ALL ABOUT ENGINEERING
- 4. “IN REALITY, PROGRAMMING LANGUAGES ARE HOW PROGRAMMERS EXPRESS AND COMMUNICATE IDEAS — AND THE AUDIENCE FOR THOSE IDEAS IS OTHER PROGRAMMERS, NOT COMPUTERS.” Guido van Rossum PRACTICAL ZEN OF PYTHON
- 5. PRACTICAL ZEN OF PYTHON THE ZEN OF PYTHON>>> import this The Zen of Python, by Tim Peters Beautiful is better than ugly. Explicit is better than implicit. Simple is better than complex. Complex is better than complicated. Flat is better than nested. Sparse is better than dense. Readability counts. Special cases aren't special enough to break the rules. Although practicality beats purity. Errors should never pass silently. Unless explicitly silenced. In the face of ambiguity, refuse the temptation to guess. There should be one-- and preferably only one --obvious way to do it. Although that way may not be obvious at first unless you're Dutch. Now is better than never. Although never is often better than *right* now. If the implementation is hard to explain, it's a bad idea. If the implementation is easy to explain, it may be a good idea. Namespaces are one honking great idea -- let's do more of those!
- 6. PRACTICAL ZEN OF PYTHON BEAUTIFUL IS BETTER THAN UGLY ▸Write codes that is nice to read and understand ▸Simple expression syntax ▸Be consistent ▸I know this is hard: pick meaningful names
- 7. PRACTICAL ZEN OF PYTHON BEAUTIFUL IS BETTER THAN UGLY - CODE EXAMPLE
- 8. PRACTICAL ZEN OF PYTHON EXPLICIT IS BETTER THAN IMPLICIT ▸State what you mean, explicitly ▸The for loop is very explicit ▸Remember, the goal is to exchange ideas ▸Leverage the Booleans ▸Be explicit and revealing when it comes to variable or function naming
- 9. PRACTICAL ZEN OF PYTHON EXPLICIT IS BETTER THAN IMPLICIT - CODE EXAMPLE
- 10. PRACTICAL ZEN OF PYTHON SIMPLE IS BETTER THAN COMPLEX ▸Always aim for simplicity ▸Do not use OOP when it’s not needed ▸Aim for lesser lines of code ▸Less code == less confusion == more clarity
- 11. PRACTICAL ZEN OF PYTHON SIMPLE IS BETTER THAN COMPLEX - CODE EXAMPLE
- 12. PRACTICAL ZEN OF PYTHON COMPLEX IS BETTER THAN COMPLICATED ▸When simple is not possible, be complex ▸Complicated can lead to misunderstanding ▸Complex code increases comprehension
- 13. PRACTICAL ZEN OF PYTHON COMPLEX IS BETTER THAN COMPLICATED - CODE EXAMPLE
- 14. PRACTICAL ZEN OF PYTHON FLAT IS BETTER THAN NESTED ‣ Use modules instead of nested if ‣ Use stdlib, it’s batteries included
- 15. PRACTICAL ZEN OF PYTHON FLAT IS BETTER THAN NESTED - CODE EXAMPLE
- 16. PRACTICAL ZEN OF PYTHON SPARSE IS BETTER THAN DENSE ‣ Be loosely coupled ‣ Do one thing and do it well - - the UNIX philosophy
- 17. PRACTICAL ZEN OF PYTHON SPARSE IS BETTER THAN DENSE - CODE EXAMPLE
- 18. PRACTICAL ZEN OF PYTHON READABLITY COUNTS ‣ Use consistent whitespace (space VS tabs) ‣ Use inline documentation ‣ Code for humans
- 19. PRACTICAL ZEN OF PYTHON READABILITY COUNTS - CODE EXAMPLE
- 20. PRACTICAL ZEN OF PYTHON SPECIAL CASE ARE NOT SPECIAL ENOUGH TO BREAK THE RULES ‣ Everything is an object ‣ The scope rule
- 21. PRACTICAL ZEN OF PYTHON ALTHOUGH PRACTICALITY BEATS PURITY, ERRORS SHOULD NEVER PASS SILENTLY, UNLESS EXPLICITLY SILENCED ‣ Python has a multi-model approach. It is: ‣ Procedural ‣ OOP ‣ Functional ‣ Errors should be handled using exceptions ‣ Graceful handling should be done via try - except
- 22. PRACTICAL ZEN OF PYTHON IN THE FACE OF AMBIGUITY, REFUSE THE TEMPTATION TO GUESS ‣ Type handling is sometimes surprising ‣ You can’t add 2 different types ‣ You can multiply them
- 23. PRACTICAL ZEN OF PYTHON THERE SHOULD BE ONE - - AND PREFERABLY ONLY ONE - - OBVIOUS WAY TO DO IT. ALTHOUGH THAT WAY MAY NOT BE OBVIOUS AT FIRST UNLESS YOU’RE DUTCH ‣ Be DRY ‣ Don’t be redundant ‣ Better learning curve ‣ Easier for distributed teams ‣ When confused, remember that the BDFL is Dutch :)
- 24. PRACTICAL ZEN OF PYTHON NOW IS BETTER THAN NEVER, ALTHOUGH NEVER IS OFTEN BETTER THAN *RIGHT* NOW‣ Ports to other language, i.e: Jython, IronPython ‣ The python 2 VS 3 battle ‣ stdlib has stricter requirements
- 25. PRACTICAL ZEN OF PYTHON IF THE IMPLEMENTATION IS HARD TO EXPLAIN, IT’S A BAD IDEA IF THE IMPLEMENTATION IS EASY TO EXPLAIN, IT MAY BE A GOOD IDEA ‣ Back to Guido’s quote on slide 3 ‣ Explain ideas through your codes ‣ Simplicity is the ultimate sophistication
- 26. PRACTICAL ZEN OF PYTHON NAMESPACES ARE ONE HONKING GREAT IDEA - - LET’S DO MORE OF THOSE ‣ Closures for better module separation ‣ Fun to use
- 27. SO WHAT’S NEXT?
- 28. PRACTICAL ZEN OF PYTHON KEY TAKEAWAYS ▸Make your code understandable ▸Simplicity is the ultimate sophistication ▸When in doubt, “import this” ▸Do it today
- 29. QUESTION S?
- 30. THANKS!!!