【ES5】hideProperty

function hideProperty(host, name, value) {
    Object.defineProperty(host, name, {
        value: value,
        writable: true,
        enumerable: false,
        configurable: true
    })
}

var obj = {
    a: 1,
    b: 2
}

console.log(Object.keys(obj)) //["a", "b"]
for (var p in obj) console.log(p) // a // b
console.log('-------------------------')
hideProperty(obj, "a", obj.a)
console.log(Object.keys(obj)) // ["b"]
for (var p in obj) console.log(p) // b
console.log(obj.a) // 1