Throttle

What does throttle do?

It throttles the function 😀👍

/**
 * Throttle in TypeScript
 * @param func Function to be throttled
 * @param delay Number of milliseconds to delay
 * @returns A new function that wraps the given function
 */

const throttle: (func: Function, delay: number) => Function = (func, delay) => {
    let isThrottled: boolean;

    return function() {
        const context = this;
        const args = arguments;

        if (!isThrottled) {
            func.apply(context, args);
            isThrottled = true;

            setTimeout(() => {
                isThrottled = false
            }, delay);
        }
    }
}

How does it work?

1. const throttle: (func: Function, delay: number) => Function = (func, delay): This line declares a constant named throttle that is assigned an anonymous function that takes in two parameters func and delay and returns a Function.

2. let isThrottled: boolean: This line declares a variable named isThrottled that is assigned a value of type boolean.

3. return function(): This line returns an anonymous function.

4. const context = this: This line declares a constant named context that is assigned the value of this.

5. const args = arguments: This line declares a constant named args that is assigned the value of arguments.

6. if (!isThrottled): This line checks if isThrottled is false.

7. func.apply(context, args): This line calls the func function and passes in the context and args as parameters.

8. isThrottled = true: This line assigns the value true to isThrottled.

9. setTimeout(() => { isThrottled = false }, delay): This line calls the setTimeout() function and passes in an anonymous function that assigns the value false to isThrottled and the delay as parameters.

Overall, the throttle function takes in a function and a delay as arguments and returns a throttled version of that function. A throttled function is a function that can only be called once every delay milliseconds.