是否可以使用静态构造函数初始化式

考虑以下类。(从一个游戏，但大大简化)

combat.h:

class Combat {
public:
    Combat();
    Combat(int health, int offense, int defense);
    virtual ~Combat();
    int  attack();
    int  defend();
    int  health() const;
    void setHealth(int health);
private:
   struct CombatImpl;
   std::unique_ptr<CombatImpl> _impl;
};

combat.cc:

struct Combat::CombatImpl {
CombatImpl();
    CombatImpl(int health, int offense, int defense);
    ~CombatImpl()=default;
    int         _health;
    int         _offense;
    int         _defense;
};
Combat::Combat(int health, int offense, int defense) :
    _impl { new Combat::CombatImpl(health, offense, defense) } {
}
Combat::~Combat()=default;
int Combat::attack() {
    int hits = 0;
    for(int i = 0; i < _impl->_offense; i++ ) {
        if (rand() % 6 == 5) {
            hits++;
        }
    }
    return hits;
}
int Combat::defend() {
    int parries = 0;
    for(int i = 0; i < _impl->_defense; i++ ) {
        if (rand() % 6 == 5) {
            parries++;
        }
    }
    return parries;
}
int Combat::health() const {
    return _impl->_health;
}
void Combat::setHealth(int health) {
    _impl->_health += health;
}
Combat::CombatImpl::CombatImpl(int health, int offense, int defense) {
    _health  = health;
    _offense = offense;
    _defense = defense;
}

monster.h:

class Monster: public Combat {
public:
    Monster(int health, int offense, int defense);
    virtual ~Monster();
}

monster.cc:

Monster::Monster(int health, int offense, int defense)
    : Combat(health, offense, defense) {}
Monster::~Monster()=default;

player.h:

class Player : public Combat {
public:
    Player();
    virtual ~Player();
private:
    struct PlayerImpl;
    static PlayerImpl _impl;
};

player.cc:

struct Player::PlayerImpl {
    PlayerImpl()=default;
    ~PlayerImpl()=default;
} Player::_impl;
Player::Player() : Combat(17, 1, 1) {
}
Player::~Player()=default;

…最后，一个使用它们的测试程序:

#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <memory>
using namespace std;
#include "monster.h"
#include "player.h"
static Monster monster(3, 1, 1);
void fight() {
    Player player;
    int damage = monster.attack();
    damage -= player.defend();
    if ( damage > 0 ) {
        player.setHealth(-damage);
    }
    if ( player.health() < 1 ) {
        return;
    }
    damage = player.attack();
    damage -= monster.defend();
    if ( damage > 0 ) {
       monster.setHealth(-damage);
    }
    if ( monster.health() < 1 ) {
        return;
    }
}
int main() {
    Player player;
    srand(time(NULL));
    while (player.health() > 0 && monster.health() > 0) {
        fight();
        printf("player health = %d    monster health = %dn", player.health(),
            monster.health());
    }
}

如果你运行这个程序，你会发现它不起作用。怪物的生命值减少了，但玩家的生命值却停留在初始值上。我认为发生这种情况的原因是这样的;玩家只有静态数据(封装在PlayerImpl _impl)这是这样的，我可以有一个全局播放器对象，我可以从不同的函数在我的代码调用。(单态模式)但它的基类Combat是动态的。每次我创建playerplayer;在fight()中，我实际上得到了一个新的Combat，其中Combat::_health是默认值。当玩家离开范围时，任何对生命值的改变都会丢失。在monster中，这不是问题，因为monster对象也有动态数据。理想情况下我可以说

 class Player : public static Combat {

表示只在这个特定的战斗中设置static，但这是一个语法错误。还有别的方法吗?还是我把自己逼入了死角?