c++ 类名和enum时重复时要在类名前加class::

一些不好的习惯都是用小写，但又没有区分开token，看看代码再说，下面的代码是我在测试polymorphism时写的一部分，怎么也查不出，最后主意到下面红色标志出来的语句，他们（animal）重复了，要区分开来。

重复名的有很多情况，以后遇见再在一起总结，先记录下来。

#include <iostream>
#include <cstring>
#include <string>

using namespace std;

enum zoo_obj_kind{
        null    = 0,
#define zk_null         (zoo_obj_kind(null))
        no      = 0,
#define zk_no           (zoo_obj_kind(no))
        animal  = 1,
#define zk_animal       (zoo_obj_kind(animal))
        plant   = 2,
#define zk_plant        (zoo_obj_kind(plant))
        others  = 3,
#define zk_others       (zoo_obj_kind(others))
        max     = 4
#define zk_max          4

};


static const char * zoo_kind_str [zk_max ] ={
        "null",
        "animal",
        "plant",
        "others"
};


class obj{
        private:
                char    name [40];
        //      void *other_msg;
        public:
                obj() {
                        strcpy(name,"null") ;
                }
                obj(char *nm){
                        strncpy(name,!nm?"null":nm,sizeof(name));
                }
                void say(){
                        cout << "name:" << name  << endl;
                }
                void say(obj *obj){
                        !obj
                                ? cout << "null\n"
                                : cout << "name:" << obj->name << endl;
                }
};
class zoo_obj{
        private:
                zoo_obj_kind z_kind;
                char    name [40];
                void *other_msg;
        public:
                zoo_obj() {
                        z_kind = null;
                        strcpy(name,"null") ;
                }
                zoo_obj(char *nm, zoo_obj_kind k){
                        strncpy(name,!nm?"null":nm,sizeof(name));
                        z_kind = k;
                }
                void say(){
                        cout << "name:" << name << ",kind:"
                                << zoo_kind_str[(int) z_kind] << endl;
                }
                void say(zoo_obj *obj){
                        !obj
                                ? cout << "null\n"
                                : cout << "name:" << obj->name << endl;
                }
};



class animal:public obj{
        private:
                int lags;
        public:

                animal(char *nm, int l) :lags(l), obj(nm){ }

                void say(){
                        obj::say();
                        cout << "lag:" << lags << endl;
                }
};

int main(void){

        zoo_obj obj = zoo_obj( "cat", zoo_obj_kind(animal));
        obj.say();

        class::animal dog ("joel's dog",4);
        dog.say();


}