js深拷贝

function deepClone(obj){
     if(obj instanceof RegEpx)   return new RegEpx(obj)
     if(obj instanceof Date)  return new Date(obj)
     if(typeof obj !=='object') return obj
     let arr=Array.isArray(obj)?[]:{}
     for(let key in obj){
          if(obj.hasOwnProperty(key)) {
              if(typeof obj[key]==='object'){
                 arr[key]=deepClone(obj[key])  
            }else{
                 arr[key]=obj[key]
             }
        }  
    }
      return arr
}