DEV Community: Sagar Gnawali

All about typeof

Sagar Gnawali — Sun, 17 Jul 2022 10:25:11 +0000

How to Highlight potential problems in React application?

Sagar Gnawali — Sat, 30 Apr 2022 05:48:39 +0000

StrictMode
-> Identifying components with unsafe lifecycles
-> Warning about legacy string ref API usage
-> Warning about deprecated findDOMNode usage
-> Detecting unexpected side effects
-> Detecting legacy context API
-> Detecting unsafe effects

Strict mode checks are run in development mode only; they do not impact the production build.
For More: https://reactjs.org/docs/strict-mode.html

Got some Javascript project

Sagar Gnawali — Mon, 11 Jan 2021 17:03:01 +0000

https://javascript30.com/?ref=java5cript.com

Day 6 -> 40 days of code

Sagar Gnawali — Wed, 25 Nov 2020 16:50:46 +0000

Nothing

Day 5 -> 40 days of code.

Sagar Gnawali — Tue, 24 Nov 2020 15:44:13 +0000

If we defined any variable and don't assign any value to it and if console.log() it then it will show undefined this happened with only var and let keyword.

In JavaScript hoisting is the default behavior of moving all the declaration at the top of the scope before code execution.
Hoisting is only happen with var.
To avoid hoisting always define a variable at the top of the program.

Let's see what does it means in coding part.
eg.
console.log(x);//undefined
var x;

eg.
var a=10;
const print =()=>
{
console.log(a);//undefined
var a;
}
print();

Here we see that a prints undefined because of hoisting.
If we remove the var a from the print function then it will print a as 10.

Day 4 -> 40 days of code.

Sagar Gnawali — Mon, 23 Nov 2020 17:56:48 +0000

Arrow function
It's the shortest function which we can use in the JavaScript.
It's just simple like other function the only difference is it use => that's why we think it's complicated. In real it's the simplest way to declare a function in JavaScript.
Let's see what does it mean
Normal function.
eg.
function printdata(x)
{
console.log(x);
}
printdata('normal function');

On the other hand if we use arrow function it's looks like this
eg.
const printdata = (x)=>
{
console.log(x);
}
printdata('arrow function');

Just do some task using arrow function like factorial of a number , basic calculation by passing parameters eg. Adding, multiplication. Then you will get to know more about this function.

Day 3 -> 40 days of code.

Sagar Gnawali — Sun, 22 Nov 2020 15:49:40 +0000

Anonymous function
In general we can say that the function which haven't any name are known as anonymous function.
Let's see what does it mean
General function have their function name
eg.
function printdata ()
{
console.log('general function');
}
printdata();

On The other hand we have anonymous function which haven't any name.In JavaScript we store function in some variable name which is known as anonymous function.
eg.
const printdata = function()
{
console.log('Anonymous function');
}
printdata();

Usage:

Anonymous function are passed as an argument to other function.

And if you have unconventional output don't be afraid of it.
This is the first step to learn something new.
Sometimes unconventional code/output brings great idea to solve bugs.

Day 2 -> 40 days of code

Sagar Gnawali — Sat, 21 Nov 2020 16:06:08 +0000

Portals provide a first-class way to render children into a DOM node that exists outside the DOM
Hierarchy of the parent component.
A React portals provides a way to render an element outside of its component hierarchy ie in a separate component.

Syntax: ReactDOM.createPortal(child,container)

Usage:
->floating menus
->widgets

Day 1 -> 40 days of code.

Sagar Gnawali — Fri, 20 Nov 2020 18:59:14 +0000

shallow comparison operator.
When it comes to string a(sc)b returns true and in case of array and object it returns false.
ie for primitive data types a(sc)b true and for complex data types a(sc)b false.

Let's check
var a="data";
var b="data";
var a=c;
console.log(a===b,a===c);//true,true

var a=[1,2,3];
var b=[1,2,3];
var a=c;
console.log(a===b,a===c);//false,true