JAVASCRIPT

JavaScript find elements in array that matches another array

let haveItList = ['apples', 'milk', 'bread', 'peanutbutter'];
let wishList = ['cookies', 'bread', 'jam', 'peanutbutter', 'bananas', 'cheese'];

let inBothLists = wishList.filter(element => haveItList.includes(element));
// inBothLists = ['apples', 'bread', 'peanutbutter'];

javascript check if elements of one array are in another

const found = arr1.some(r=> arr2.includes(r))

How to check if array includes a value from another array in JavaScript

// How to check if array includes a value from another array in JavaScript
const includesAny = (arr, values) => values.some(v => arr.includes(v));
includesAny([1, 2, 3, 4], [2, 9]); // true
includesAny([1, 2, 3, 4], [8, 9]); // false

how to check all elements in array includes in another array javascript

// how to check all elements in array includes in another array javascript
const includesAll = (arr, values) => values.every(v => arr.includes(v));
includesAll([1, 2, 3, 4], [1, 4]); // true
includesAll([1, 2, 3, 4], [1, 5]); // false

find new values in array based on another array apps script

// elements to filter out.
const keys = [['a','b','c']],
keySet = new Set(keys[0]),

// example data.
data = [['a',1,2],
        ['c',4,3],
        ['d',3,4]],
out = data.filter(([item0])=>!keySet.has(item0));
console.info(out);

if array ontains any item of another array js

const found = arr1.some(r=> arr2.indexOf(r) >= 0)

find items in array not in another array javascript

var arr1 = [
    {
      "prop1": "value1",
      "prop2": "value2",
    },
    {
      "prop1": "value3",
      "prop2": "value4",
    },
    {
      "prop1": "value5",
      "prop2": "value6",
    },
  ];

var arr2 = ['value1','value3', 'newValue'];

// finds all the elements of arr2 that are not in arr1
arr2.filter( 
    val => !arr1.find( arr1Obj => arr1Obj.prop1 === val)
); // outputs "newValue"

find new values in array based on another array apps script

const ObjectOfKeys = keys.reduce((acc,rec)=> {
                        let nextAcc = acc;
                        nextAcc[rec] = true;
                        return nextAcc;
                        },{});

const filteredData = data.filter(rec => !ObjectKeys[rec[0]])

find new values in array based on another array apps script

const ObjectOfKeys = keys.reduce((acc,rec)=> {
                        let nextAcc = acc;
                        nextAcc[rec] = true;
                        return nextAcc;
                        },{}};

const filteredData = data.filter(rec => !ObjectKeys[rec[0]])

find new values in array based on another array apps script

const ObjectOfKeys = keys.reduce((acc,rec)=> {
                        let nextAcc = acc;
                        nextAcc[rec] = true;
                        return nextAcc;
                        },{}};

const filteredData = data.filter(rec => !ObjectOfKeys[rec[0]])

find new values in array based on another array apps script

const ObjectOfKeys = keys.reduce((acc,rec)=> {
                        let nextAcc = acc;
                        nextAcc[rec] = true;
                        return nextAcc;
                        },{});

const filteredData = data.filter(rec => !ObjectOfKeys[rec[0]])