let arr = [[1, 2], [3, 4]]
let list = arr.map(([a, b]) => a + b);
console.log(arr)
console.log(list)
function move({x = 0, y = 0}) {
console.log([x,y])
return [x, y];
}
move({x: 3, y: 8} ); // [3, 8]
move({x: 3}); // [3, 0]
move({}); // [0, 0]
//move(); // [0, 0]