[proxy => { proxy.val += 1; }, proxy => { proxy.val -= 1; }]

{"arr":[1,2,3]}

[proxy => { proxy.arr[0] = 5; proxy.newVal = proxy.arr[0] + proxy.arr[1]; }]

{"obj":{"val":{"x":10,"y":20}}}

[proxy => { let data = proxy.obj.val; let temp = data.x; data.x = data.y; data.y = temp; }]