深拷贝 浅拷贝

var person={    name:'cj',    age:22,    address:{        home:"home address",        office:"office address"    },    school:["xiaoxue","daxue"]};var programer={    language:"javascript"
};
function extend(p,c){    c=c || {};    for(var prop in p){        if(typeof p[prop]==='object'){            c[prop]=(p[prop].constructor===Array?[]:{});            extend(p[prop],c[prop]);        }else{            c[prop]=p[prop];        }    }}