Array.prototype.slice.call

Array.prototype.slice.call(obj)

obj继承array的所有原形方法(prototype)；
obj有一下限制

Array.prototype.slice.call({name: 'obj'}) ;  //[]
Array.prototype.slice.call({0: 'zero', 2: 'one', length: 2});  //["zero", empty]
Array.prototype.slice.call({name: 'zero', age: 'one', length: 2});  //[empty × 2]
Array.prototype.slice.call('sss');  //["s", "s", "s"]
Array.prototype.slice.apply('abc123!');  //["a", "b", "c", "1", "2", "3", "!"]
Array.prototype.slice.call({0: 'zero', 1: 'one', name: 'obj', length: 2});   //["zero", "one"]