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Kartik Mehta
Kartik Mehta

Posted on • Edited on

Understanding JavaScript Prototypes

Introduction

JavaScript is a popular programming language used for creating dynamic and interactive web pages. One of the key features of JavaScript is prototypes, which play a crucial role in the language. Prototypes are objects that serve as a blueprint for creating other objects and provide functionalities to these objects. In this article, we will dive deeper into understanding JavaScript prototypes and their advantages, disadvantages, and features.

Advantages of JavaScript Prototypes

  1. Efficient Code Reuse: Prototypes make it easier to create and manage objects in JavaScript. They allow for the efficient reuse of code, reducing the amount of code needed to be written.

  2. Flexibility and Dynamic Object Building: Prototypes also provide a flexible and dynamic approach to building objects, allowing for changes to be made easily at runtime.

Disadvantages of JavaScript Prototypes

  1. Potential for Conflicts and Bugs: One of the main drawbacks of prototypes is the potential for conflicts and unintended modifications to objects. If not carefully managed, changes made to a prototype can affect all objects that inherit from it, creating unexpected bugs in the code. This can make debugging and troubleshooting a more challenging task.

Features of JavaScript Prototypes

  1. Prototypal Inheritance: Prototypes have some key features that make them stand out in the JavaScript language. One of the most notable features is prototypal inheritance, which allows objects to inherit properties and methods from their prototypes.

    function Vehicle(make, model) {
        this.make = make;
        this.model = model;
    }
    
    Vehicle.prototype.displayInfo = function() {
        console.log(`Make: ${this.make}, Model: ${this.model}`);
    };
    
    const car = new Vehicle('Toyota', 'Corolla');
    car.displayInfo();  // Output: Make: Toyota, Model: Corolla
    
  2. Dynamic Modifications: Another important feature is the ability to modify and extend a prototype at runtime, providing a more dynamic approach to coding.

    Vehicle.prototype.year = 2020;
    car.year = 2021;
    console.log(car.year);  // Output: 2021
    

Conclusion

In conclusion, understanding JavaScript prototypes is crucial for any developer looking to master the language. While they provide numerous advantages, it is essential to be aware of their potential drawbacks and use them with caution. Prototypes are a powerful feature of JavaScript, and when used correctly, can greatly enhance the efficiency and flexibility of code.

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typescript

1 Think in {Set}

Type is an everyday concept to programmers, but it’s surprisingly difficult to define it succinctly. I find it helpful to use Set as a conceptual model instead.

#2 Understand declared type and narrowed type

One extremely powerful typescript feature is automatic type narrowing based on control flow. This means a variable has two types associated with it at any specific point of code location: a declaration type and a narrowed type.

#3 Use discriminated union instead of optional fields

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