export default function (obj, keys, val) { keys.split && (keys=keys.split('.')); var i=0, l=keys.length, t=obj, x, k; for (; i < l;) { k = keys[i++]; if (k === '__proto__' || k === 'constructor' || k === 'prototype') continue; t = t[k] = (i === l ? val : ((x=t[k]) != null ? x : (keys[i]*0 !== 0 || !!~keys[i].indexOf('.')) ? {} : [])); } }