Misconception about classes?

[cpudaman]

I was under the impression that all the functions in a class shared the variables that were defined in the class. Was I mistaken? My compiler keeps telling me that the variables in the class haven't been declared in the functions within the class that I use them in. So I guess I was wrong. If I am wrong, is there an easy way to solve this?

[XSquared]

Could you post some minimal code that reproduces the issue, please?

[cpudaman]

class creature {
	public:
	creature () {}
	~creature () {}
	int attack () {
		power = basic_dmg + mod_dmg;
		return power;
	}
	void takedmg ( int dmg ) {
		dmg = dmg - armor;
		health = health - dmg;
	}
	private:
	int basic_dmg, mod_dmg, power, dmg, armor, health;
};

error: 'power' undeclared. first use this function.
error: 'basic_dmg' undeclared. first use this function.

and so on for all the other variables, except for the ones within the arguments

[robwhit]

class creature {
    private:
    int basic_dmg, mod_dmg, power, dmg, armor, health;
    public:
    creature () {}
    ~creature () {}
    int attack () {
        power = basic_dmg + mod_dmg;
        return power;
    }
    void takedmg ( int dmg ) {
        dmg = dmg - armor;
        health = health - dmg;
    }
};

[laserlight]

That's rather strange. Your code looks correct, and compiles without errors on the MinGW port of g++ 3.4.5, MSVC8, and the online Comeau compiler. There should be no need to change it to robwhit's example. What compiler are you using?

[cpudaman]

for writing purposes, i use codeblocks.

[cpudaman]

my example compiles fine...hmmm, I thought I included the problem, here is the full class

class player {
    public:
        player (int health, int intelligence, int strength, int agility,
                int stamina, int armormin, int armormax, string weap1name,
                string weap1descr, string weap1shrtdescr, int weap1dmg,
                int weap1moddmg, int weap1modtype, string weap2name,
                string weap2descr, string weap2shrtdescr, int weap2dmg,
                int weap2moddmg, int weap2modtype, string weap3name,
                string weap3descr, string weap3shrtdescr, int weap3dmg,
                int weap3moddmg, int weap3modtype ) {
        }
        ~player () {}

        int getagility ( void ) {
            return agility;
        }

        int attack ( void ) {
            cout << "Select you weapon of destruction\n\n";
            cout << "1. " << weap1name << "\n";
            cout << "2. " << weap2name << "\n";
            cout << "3. " << weap3name << "\n";
            cin >> choice;
            cin.ignore();
            switch ( choice ) {
                case 1:
                weap1dmg = dmg;
                break;
                case 2:
                weap2dmg = dmg;
                break;
                case 3:
                weap3dmg = dmg;
                break;
                default:
                cout << "Don't be an idiot\n" << "You need to make a choice\nNow no attack for you!\n";
                cin.get();
                clrscrn();
                break;
            }
            return dmg;

        }
        void takedmg( int dmg, int enemyagility) {
            if (agility > enemyagility) {
                agilitydif = agility - enemyagility;
            }
            if (agilitydif < 10) {
                dmg = (dmg * ( 1 - ( agilitydif / 10 ) ) );
                def = rand() &#37; (armormax - armormin + 1) + armormin;
                dmg = dmg - def;
                if (dmg < 0) {
                    dmg = 0;
                }
                if (dmg != 0) {
                    cout << "Your armor blocked " << def << "DMG.\n";
                    cout << "\nYou took " << dmg << " DMG.\n:";
                    health = health - dmg;
                    cout << "\nYour health is down to " << health << " HP.\n";
                    cin.get();
                    clrscrn();
                }
                if (dmg == 0) {
                    cout << "No Damage Taken\n\n";
                    cout << "HP remains at " << health;
                    cin.get();
                    clrscrn();
                }
            }
            if ( enemyagility <= agility ) {
                cout << "You dodged the attack";
                cin.get();
                clrscrn();
            }
        }

    private:
        int health, intelligence, strength, agility, stamina, armormin, armormax;
        int choice, enemyagility, agilitydif, dmg, def;

};

[XSquared]

In your example, things such as weap1name are only declared as parameters in your class constructor, not as actual instance variables. You'll need to add declarations for them within the class itself.

[laserlight]

for writing purposes, i use codeblocks.

Good for you, but I asked about compiler, not IDE. CodeBlocks might use g++, or perhaps a Microsoft compiler, or yet other compilers.

my example compiles fine...hmmm, I thought I included the problem, here is the full class

It is a good idea to test your examples before posting them
Anyway, I believe XSquared got it right.

That said, you may want to improve your class design a little. Trying to store everything about the player directly in the player class can be a little cumbersome. It may make sense to create other classes, e.g., armor and weapon classes.

[cpjust]

my example compiles fine...hmmm, I thought I included the problem, here is the full class

class player {
    public:
        player (int health, int intelligence, int strength, int agility,
                int stamina, int armormin, int armormax, string weap1name,
                string weap1descr, string weap1shrtdescr, int weap1dmg,
                int weap1moddmg, int weap1modtype, string weap2name,
                string weap2descr, string weap2shrtdescr, int weap2dmg,
                int weap2moddmg, int weap2modtype, string weap3name,
                string weap3descr, string weap3shrtdescr, int weap3dmg,
                int weap3moddmg, int weap3modtype ) {
        }
        ~player () {}

        int getagility ( void ) {
            return agility;
        }

        int attack ( void ) {
            cout << "Select you weapon of destruction\n\n";
            cout << "1. " << weap1name << "\n";
            cout << "2. " << weap2name << "\n";
            cout << "3. " << weap3name << "\n";
            cin >> choice;
            cin.ignore();
            switch ( choice ) {
                case 1:
                weap1dmg = dmg;
                break;
                case 2:
                weap2dmg = dmg;
                break;
                case 3:
                weap3dmg = dmg;
                break;
                default:
                cout << "Don't be an idiot\n" << "You need to make a choice\nNow no attack for you!\n";
                cin.get();
                clrscrn();
                break;
            }
            return dmg;

        }
        void takedmg( int dmg, int enemyagility) {
            if (agility > enemyagility) {
                agilitydif = agility - enemyagility;
            }
            if (agilitydif < 10) {
                dmg = (dmg * ( 1 - ( agilitydif / 10 ) ) );
                def = rand() % (armormax - armormin + 1) + armormin;
                dmg = dmg - def;
                if (dmg < 0) {
                    dmg = 0;
                }
                if (dmg != 0) {
                    cout << "Your armor blocked " << def << "DMG.\n";
                    cout << "\nYou took " << dmg << " DMG.\n:";
                    health = health - dmg;
                    cout << "\nYour health is down to " << health << " HP.\n";
                    cin.get();
                    clrscrn();
                }
                if (dmg == 0) {
                    cout << "No Damage Taken\n\n";
                    cout << "HP remains at " << health;
                    cin.get();
                    clrscrn();
                }
            }
            if ( enemyagility <= agility ) {
                cout << "You dodged the attack";
                cin.get();
                clrscrn();
            }
        }

    private:
        int health, intelligence, strength, agility, stamina, armormin, armormax;
        int choice, enemyagility, agilitydif, dmg, def;

};

I see a bunch of undeclared variables.

[cpudaman]

Thanks for all the help, I got the problem fixed and understand what I did wrong.

]
That said, you may want to improve your class design a little. Trying to store everything about the player directly in the player class can be a little cumbersome. It may make sense to create other classes, e.g., armor and weapon classes.

I'll try to improve the organization, but I wanted there to be a separate function for the fighting, than there was for the scenario stuff.

[Salem]

All those variables with 1,2,3 in them are screaming to be arrays, or better yet, std::vector's

[King Mir]

They also scream of being put into a single weapon struct.