Mastering the language of the web. From basic types to advanced generics and patterns.
During recent developer interviews, I noticed many candidates felt overwhelmed by coding challenges. For junior positions, it's common to be asked about basic JavaScript tasks. Today, I'll share essential data manipulation techniques that junior deve...
When coding in TypeScript or Angular and embracing types, sometimes we don't pay attention to "Circular dependencies". We create types and try to use them everywhere to match with the existing structure, and if we're not careful, it's so easy to crea...
When we create applications in Angular, the any type is our "live-saver" when struggle with complex error messages, want to save time by not writing specific type definitions, or think that TypeScript's type checking limits our coding flexibility and...
Today, I reviewed a piece of code where a variable could be of two types, but to enhance readability, the simple method is to use union and intersection. In this example, we have defined two interfaces, Player and Basket, each representing a specific...
A few days ago, a friend asked how to prevent duplicate keys in an array, and I told him there are other collections to work with, and each one is suited for a specific situation. Because I love the NBA, I tried to find an easy way to explain each da...
Today I was facing a problem where I wanted an object with a list of properties but with specific values like: For example: export type NBATeam = "Lakers" | "Celtics" | "Bulls" | "Warriors"; const nbaChampionships = { Lakers: 17, Celtics: 17...
TypeScript offers powerful features that make code more concise and efficient. Two such features, optional chaining and nullish coalescing, play a vital role in handling data effectively. In this article, we'll explore these features within the conte...
I was assisting a friend in constructing a sorting table with data in Typescript and he ran into some odd behavior along the way. In this lesson, we will explore what occurs in Javascript when the sort method is used with strings and numbers. Sorting...
In Typescript, we have to check for values types like boolean, string, object instance from class, and the values in objects. 馃憠馃徑 Why pay for hosting? Click here to deploy your Angular apps for free on a reliable VPS In Typescript, we have three w...
When we use types or interfaces, the typescript compiler enforces the object fit with them to avoid runtime errors for missing fields. Sometimes we want the flexibility to create an object without breaking the contract with the interface type. For ex...
Typescript is a technology that grows every day. Companies like Slack, Airbnb, or Google are changing their javascript codebase to Typescript. Frameworks like Vue, React, and (Angular) are using Typescript for writing maintainable code. These steps s...
Sometimes we have a long list of imports, with files that come from the same place, it makes our code noisy and a bit longer, something like: import { BeersService } from './services/beers.service'; import { WhiskyService } from './services/whiski....
I'm refactoring an Angular code, and I need to have the same filenames while finishing the refactor. My solution was to rename my imports. It is a great way to use a different name or alias for my classes and modules. For example, you can import a si...
Today, a friend ask about the difference between extends and implements. class Media { format: string; } class Video extends Media {} class Image implements Media {} The short answer for him was: extends: The class get all these methods and proper...
I want to show a small overview of the typescript compiler, and the tsc is responsible for compiling our typescript code, watching changes, code checking, and more. The tsc accept parameters on the execution process can read the configuration from th...
In typescript or Angular apps, we can avoid having ugly paths like the following example. import { BookMark } from 'src/app/models/bookmark'; import { BookmarksState } from './../../../state/bookmarks.state'; import { GetBookMark } from './../../../s...
I was talking about class decorators in Typescript in my previous post; today is time for properties decorators to define and use them for writing clean and elegant code. What is Property Decorator The property decorator is a function applied to the ...
The Decorators are an excellent Typescript feature; maybe you see them all over Angular and other frameworks. It helps to write code clean and declarative, maybe you already use it every day, but do you know when to create your decorators? I will s...
The interface is an excellent Typescript feature and helps to write structured and explicit code. The interface helps you describe a structure like fields without values or methods without implementation and forces objects and classes to have. Interf...
In Typescript, the classes can inherit from another class to share methods and properties between classes. Also, Typescript support abstract class. Let me show you why and when to use it. For example, we have a base class Subscription and create the ...
The encapsulation is an essential part of OOP, and Typescript support gets and sets keywords for members of classes. The encapsulation can be used with the get and set keywords before a function name, then using it. We can encapsulate some logic and ...
If there is one thing I have to admit, it is that Typescript allows us to feel in control in javascript and that is also thanks to the typings (tsd), but some libraries don't have the typings, I have found myself in need of writing the typings of the...
The Typescript language understands the functions return type by default; for example, in the following example, the compiler understands one return boolean and the other is void. function Auth() { return true } function Auth() { console.log("he...
Typescript comes with its types, and each one is part of typescript, not javascript. Typescript will provide these types as part of our development process, notify the compiler of the data type used, and force us to implement them appropriately. Tupl...
I am starting to move to Typescript. I discover how works type annotations in typescript functions. Let start by showing a few things I learned today about Typescript. Typescript allows type annotation in function parameters and returns types. Types ...
I am starting to move to Typescript. I discover how it works and different ways to use them with Typescript. Typescript is a superset running up to Javascript, and it supports all primitive types. Let start by showing a few things I learned today abo...