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Set and Array in Javascript

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 Set: 

The set object lets you store unique values of any type

const arr1 = [1, 2, 3, 1, 2, 'name']
const set1 = new Set(arr1)
const arr2 = Array.from(set1)
console.log(arr2)
// [ 1, 2, 3, 'name' ]

add object or array to Set, can't use "has" or "delete"

set1.add([1])
console.log(set1.has([1])) // false
set1.delete([1])
// false

convert to Array

const arr2 = Array.from(set1)
const arr3 = [...set1]


Set for string, remove duplicated letters

const text = 'IndiaIndia';
const mySet = new Set(text);
console.log( [...mySet], text.split(''))

[ 'I', 'n', 'd', 'i', 'a' ]
[ 'I', 'n', 'd', 'i', 'a', 'I', 'n', 'd', 'i', 'a' ]



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