TypeScript is a superset of JavaScript that introduces static typing and other features. While JavaScript is dynamically typed, TypeScript allows developers to define types, catching errors during the development phase and improving code quality.
How to write a "Hello World" program in TypeScript
Key Takeaways
By adding static types, TypeScript helps in building more reliable and maintainable codebases.
Writing and running a "Hello World" program teaches the basic syntax and structure of TypeScript.
TypeScript's ability to infer types reduces the need for explicit type annotations, resulting in cleaner and more concise code.
The first step to getting familiar with a new language is to write a simple "Hello World" program, and the same goes for TypeScript. TypeScript, a superset of JavaScript, is widely used for adding static typing to JavaScript.
What is TypeScript?
TypeScript is a language on top of JavaScript. Everything possible in JavaScript is available in TypeScript – it is a superset of JavaScript. It builds on JavaScript by adding optional static typing, making it easier to write and maintain code in large applications. With TypeScript, you can write robust, bug-free code and enjoy improved tooling support.
Hello World in TypeScript
Some of the key features of TypeScript are:
Enables type checking at compile time.
Supports modern JavaScript features and compiles down to compatible versions for broader browser support.
Provides features like classes, interfaces, and inheritance.
Want to build a real-world application with TypeScript? Try this project: Genius TypeScript Discord Bot, where we create a basic, functional Discord bot.
There are several ways to write a simple TypeScript program that prints "Hello World" to the console. Let's look at each below.
Explicit type annotation
In the example below, we demonstrate how to write a "Hello World" text in TypeScript by explicitly mentioning the type of the variable.
// Declare and initialize 'message' of type string to 'Hello World'.let message: string = 'Hello World';// Printing the message to console.console.log(message);
In the example above, we declare a variable message of type string, and initialize it to "Hello World", explicitly mentioning the type string. We then print the value of message to the console.
Type inference in TypeScript
TypeScript also supports type inference, which enables it to automatically determine the type of a variable based on the value assigned to it. This capability reduces the requirement for explicit type declarations, resulting in code that is more streamlined and easier to read. Consider the following code:
// Declare and initialize 'message'.let message = 'Hello World';// Printing the message to console.console.log(message);
In the example above, we do not explicitly specify the type of message. TypeScript infers that message is of type string based on the assigned value.
Enhance your understanding of TypeScript and its related concepts with the help of this project, Automate Login-Workflow Testing with Playwright, where we test a web app using the browser automation features provided by the Playwright library in TypeScript.
Writing a "Hello World" program in TypeScript is a simple yet effective way to get acquainted with this language. Leveraging TypeScript's type inference capabilities allows you to write cleaner and more efficient code without sacrificing type safety.
Frequently asked questions
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