Js | Truthy & Falsy |

Truthy and Falsy Values:

in Javascript, truthy and falsy values are used to determine whether a value evaluate to true or false in a boolean
context.this concept is crucial for controlling the flow of your program using conditions like if statement.

Falsy Values: 0," ",null,NaN,false,undefined 

console.log(Boolean(0)); //false

console.log(Boolean(undefined)); //false

console.log(Boolean(' '));  //empty false

console.log(Boolean(null)); //false

console.log(Boolean(NaN)); //false not a number

console.log(Boolean(false)); //false

Truthy Values: any value that is not Falsy :

console.log(Boolean(1)); //true

console.log(Boolean(1833933)); //true

console.log(Boolean(-1)); //true

console.log(Boolean("hello")); //true

console.log(Boolean(1)); //true

console.log(Boolean([])); //true empty array

console.log(Boolean({})); //true empty object

console.log(function (){}); //true

Example:

           t     f
let cash =255  //0 ; 
    //conditions false  statement block not run
if (cash){
  console.log("you can buy burger with drink"); 
}else{
   console.log("you can buy burger"); 
}else{
   console.log("you don't have money"); 
}

let a;
console.log(a); //false

output:
undefined 

let a = 10;
console.log(a); //true

let a = null;
console.log(a); //false

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