What is Anonymous Function in TypeScript?

In TypeScript, anonymous functions are also known as 'nameless functions' or 'lambda functions'. These functions do not have specific names and are commonly used when temporary functions need to be created. Anonymous functions can be implemented as function expressions or arrow functions. They are frequently employed in callback functions, event handling, or any scenarios where the function does not require multiple references.

Function Expression Example:

typescript
let show = function(message: string) {
    console.log(message);
};

show("Hello TypeScript");

In this example, the function is invoked via the variable show, and it lacks a specific name.

Arrow Function Example:

typescript
let greet = (name: string) => console.log(`Hello, ${name}!`);

 greet("Alice");

Arrow functions offer a more concise syntax for defining anonymous functions, resulting in clearer and more readable code.

Application Scenarios:

Suppose we are developing a web application using TypeScript and need to handle user click events with an anonymous function in a button click event:

typescript
document.getElementById("myButton").addEventListener("click", function() {
    console.log("Button clicked!");
});

Here, an anonymous function is directly defined within the addEventListener method to handle the click event. This approach is concise and direct, as no named function needs to be defined elsewhere, especially when the function is not intended for reuse.

Overall, anonymous functions in TypeScript provide a flexible way to handle specific logic that does not require reuse, making the code clearer and more concise.