Lesson 51 of 55
15 mins readPython Decorators and Metadata Reflection
In Plain English
Decorators provide a declarative way to instrument, log, modify, or observe class definitions and their methods, widely used in modern frameworks.
Core Rules to Remember
Class Decorators: Wraps constructors to add metadata, dependency injection, or telemetry.
Method Decorators: Instruments method execution with logging, authorization, and caching.
Live Interactive Example
Hit Run Code to see it liveApplying Method Instrumentation Decorator Pattern
Python 3.12
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Output Console
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How it works: Decorators wrap class methods or constructors to provide cross-cutting concerns.
Your Turn: Micro Challenge
No pressure! Edit the starter code below and test your solution with instant feedback.
Micro Exercise
Implement a Simple Timing Wrapper
- Write function withTiming<T>(fn: () => T, label: string): T that prints `[Start: ${label}]`, executes fn(), and returns the result.
- Run with fn returning 100 * 2 with label "compute" and print `Returned: ${result}`.
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Sandbox Output
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