Choosing Between a Class or an Object

Question

Choosing Between a Class or an Object

I was exploring the Angular official tutorial and stumbled upon an intriguing example of a simple class (https://angular.io/tutorial/toh-pt1). In this example, they demonstrated using the class as if it were an object, which left me puzzled.

class Hero{
     id: number;
     name: string

They showcased its usage like this...

const HEROES: Hero[] = [
       { id: 11, name: 'Mr. Nice' },
       { id: 12, name: 'Narco' },
       { id: 13, name: 'Bombasto' },
       { id: 14, name: 'Celeritas' },
    ];

This list was then utilized in the HTML code. (https://angular.io/tutorial/toh-pt2)

As someone new to Typescript, I found myself perplexed by this concept. In languages like Python, classes need to be instantiated to be used. While I am aware that objects can be created and utilized similarly in Javascript, I have never encountered it being done with the class keyword.

I embarked on a search through Google, watched various videos on Typescript, yet failed to find similar examples elsewhere. If anyone could guide me towards relevant documentation or provide a straightforward explanation with examples, I would greatly appreciate it!

typescript

Answer 1

Answer №1

This explanation provides a basic overview of JavaScript concepts. In JavaScript, using {} creates an object, while { id: 5 } creates an object with an 'id' field set to 5.

JavaScript utilizes "duck typing", where matching "type" with a class is based on shared members rather than an explicit type definition. Although TypeScript adds type checking capabilities, the underlying object still lacks intrinsic type.

Additionally, TypeScript includes powerful type inference that can determine the appropriate type for objects based on their member structure, as illustrated by inferring Hero in this context.

Answer 2

This explanation provides a basic overview of JavaScript concepts. In JavaScript, using {} creates an object, while { id: 5 } creates an object with an 'id' field set to 5.

JavaScript utilizes "duck typing", where matching "type" with a class is based on shared members rather than an explicit type definition. Although TypeScript adds type checking capabilities, the underlying object still lacks intrinsic type.

Additionally, TypeScript includes powerful type inference that can determine the appropriate type for objects based on their member structure, as illustrated by inferring Hero in this context.

Answer 3

Answer №2

Dealing with this issue was quite perplexing for me too. Upon utilizing the class keyword, I believe using new to create instances becomes more logical.

It goes beyond being merely 'syntactic sugar'; it pertains to establishing a systematic workflow.

If you lean towards Javascript syntax for handling objects, Typescript offers a method to specify a Type for an object:

type Superhero = { id: number, name: string }

const Superheroes: Superhero[] = [
    {id:3, name:"henk"}
]

Answer 4

Dealing with this issue was quite perplexing for me too. Upon utilizing the class keyword, I believe using new to create instances becomes more logical.

It goes beyond being merely 'syntactic sugar'; it pertains to establishing a systematic workflow.

If you lean towards Javascript syntax for handling objects, Typescript offers a method to specify a Type for an object:

type Superhero = { id: number, name: string }

const Superheroes: Superhero[] = [
    {id:3, name:"henk"}
]

Answer 5

Answer №3

Take a moment to review the documentation.

Create a constant called HEROES with an array containing ten heroes.

Do you grasp the concept here? We are taking an array of identifiers and names, and assigning them to a collection of hero elements. A simplified version would look like this:

const HERO: Hero = { id:21, name: 'myName'};

Although it resembles a structure, experimenting here demonstrates that it simplifies to

var HERO = { id: 50, name: 'test' };

. While there are other methods to achieve immutability for an object, they can be quite cumbersome in syntax. This approach serves as a shorthand way to instantiate objects in one "line" (i.e., before a semicolon).

Answer 6

Take a moment to review the documentation.

Create a constant called HEROES with an array containing ten heroes.

Do you grasp the concept here? We are taking an array of identifiers and names, and assigning them to a collection of hero elements. A simplified version would look like this:

const HERO: Hero = { id:21, name: 'myName'};

Although it resembles a structure, experimenting here demonstrates that it simplifies to

var HERO = { id: 50, name: 'test' };

. While there are other methods to achieve immutability for an object, they can be quite cumbersome in syntax. This approach serves as a shorthand way to instantiate objects in one "line" (i.e., before a semicolon).

Choosing Between a Class or an Object

Answer №1

Answer №2

Answer №3

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