js中深拷贝代码实现

function copy(original,o){
    if(typeof original != 'object') return original;

    var o = o || (Array.isArray(original) ? [] : {});

    for(var i in original){
       if(typeof original[i] == 'object'){
         copy(original[i],o[i] = (Array.isArray(original[i]) ? [] : {}));
       }else{
         o[i] = original[i];
       }
    }

    return o;
}