Lesson 33 of 55
15 mins readPython Parameter Properties Shorthand
In Plain English
TypeScript allows you to turn constructor parameters into class properties by prefixing them with an access modifier or readonly keyword.
Core Rules to Remember
Boilerplate Reduction: Combines declaration, parameter receipt, and assignment in one keyword.
Cleaner Constructors: Keeps constructor body focused purely on initialization logic.
Live Interactive Example
Hit Run Code to see it liveConcise Class Definitions
Python 3.12
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Output Console
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How it works: Prefixing constructor parameters with public or private automatically declares and assigns instance fields.
Your Turn: Micro Challenge
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Micro Exercise
Refactor to Parameter Properties
- Create class Vehicle with constructor(public readonly brand: string, public speed: number).
- Add method accelerate(amount: number): number that increases speed by amount and returns speed.
- Instantiate with "ZenMotors", 60, call accelerate(20), and print brand and speed.
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Sandbox Output
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