convert matrix string to matrix javascript

var fruits = 'apple, orange, pear, banana, raspberry, peach';
var ar = fruits.split(', '); // split string on comma space
console.log( ar );
// [ "apple", "orange", "pear", "banana", "raspberry", "peach" ]

a=anyElement.all

// console.log(a)
Array.from(a).forEach(function (element){
    console.log(element)
})

string = '[[1, 2], [3, 4], [5, 6]]'

string = JSON.parse(string)