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Importance of Immutability in JavaScript

What is the good part of the immutability? Why do we need to care about the immutability in the first place? Why even bother?

Immutability gives stricter control over your data immediately making your code safer and more predictable. In other words, immutable objects allow you to control the interface and data flow in a predictable manner, discovering the changes efficiently. It also makes it easier to implement complex features such as undo/redo, time travel debugging, optimistic updates and rollback, and so on.

If we talk about the frontend library React, Vue os state management library Redux then immutability can also help achieve better performance by enabling quick and cheap comparisons between versions of the state before and after changes. Components can take advantage of this and intelligently re-render itself only when needed. This can significantly boost performance.

The main benefits of immutability are predictability, performance, and better mutation

	export const AuthGuard: CanActivateFn = (route: ActivatedRouteSnapshot, state: RouterStateSnapshot) => {
	const store = inject(Store);
	return new Promise<boolean>(resolve => {
	const sub = store.select(getAgeSelector).subscribe(res => {
	if (res && res?.token && res?.token?.length) {
	resolve(true);
	} else {
	window.open(environment.WHATEVER, '_SELF');
	resolve(false);
	}

	function deepCopy(obj) {
	if (typeof obj !== 'object' \|\| obj === null) {
	return obj; // Return primitive values and null as is
	}

	const copy = Array.isArray(obj) ? [] : {};

	for (let key in obj) {
	copy[key] = deepCopy(obj[key]);
	}

	Object.values(this.anyform.controls).filter(control => {
	if (control.invalid) {
	control.patchValue(control?.value?.length === 0 ? ' ' : control?.value);
	control.markAsDirty();
	control.markAsTouched();
	control.setErrors({ incorrect: true });
	control.updateValueAndValidity();
	}
	});

	//use of async, await, futures in dart
	import 'dart:async';

	void main() async {

	var data = await get('hi');
	print(data);
	}

	void main() {
	var to = DateTime(2023, 8, 31, 0, 0);
	DateTime now = DateTime.now();

	var d = now.difference(to);
	print(to);
	print(now);
	var remainingtime = d.abs();
	print('$remainingtime');
	}

	npx @angular/cli@16 new app --directory=./

	npx @angular/cli@8 new app --directory=./

	// Globals

	// DOM elements
	const stringOne = document.querySelector("#string-one");
	const stringTwo = document.querySelector("#string-two");
	const message = document.querySelector("#result");


	// Initialize application
	function isomorphic() {

	searchSubject = new Subject();
	searchResult$: Observable<any>;



	this.searchResult$ = this.searchSubject.pipe(
	debounceTime(1000),
	distinctUntilChanged(),
	switchMap((searchText: string) => {
	return this.service.validateZipCode(searchText)