get value in array from another value js code example

Example 1: 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);

Example 2: 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]])