javascript question mark dot code example

Example 1: javascript question mark

//This is what is called a 'Conditional operator'
let result = condition ? value1 : value2
//               ^^        ^^      ^^
let result =  1 == 2   ?  "YES" : "NO!"
console.log(result)  //output: "NO!"

//Basically a short form of an if-else statment

Example 2: optional chain operator

const adventurer = {
  name: 'Alice',
  cat: {
    name: 'Dinah'
  }
};

const dogName = adventurer.dog?.name;
console.log(dogName);
// expected output: undefined

Example 3: optional chaining

const array = [1,2,3,4,5];
let arrItem = array?.[4]; 

console.log(arrItem); /// 5

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Javascript Example

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