Lesson 14 of 55
15 mins readPython Optional, Default, and Rest Parameters
In Plain English
Learn how to mark parameters as optional (?), provide compile-time default initializers, and capture variable arguments using typed rest parameters.
Core Rules to Remember
Optional Parameters: Marked with ?, must appear after all required parameters.
Rest Tuples: Collects variable arguments into a strongly typed array or tuple.
Live Interactive Example
Hit Run Code to see it liveFlexible Function Arity
Python 3.12
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Output Console
Click "Run Code" to view the rendered output.
How it works: channel defaults to email when omitted; urgency is optional; rest numbers collect arguments.
Your Turn: Micro Challenge
No pressure! Edit the starter code below and test your solution with instant feedback.
Micro Exercise
Build a Log Formatter with Rest Tags
- Create a function formatLog(message: string, level: string = "INFO", ...tags: string[]): string.
- Format and return: `[${level}] ${message} | Tags: ${tags.join(", ")}`.
- Call formatLog("DB connected", "READY", "db", "auth") and print the result.
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Sandbox Output
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