A Lil Help With Inheritance...

Ok I Got a lil project and am seeking a bit of help with my header files (interfaces). I just want some help to clear up the headers before i jump on the implementation...Thanks in advance for your help and here is the code.

Code:

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#ifndef Insurance_header
#define Insurance_header
//Parent Class
class MainIns{
        int pol_num;//policy number
        string pol_hol;//policy holder
        int eff_date;//effective date of policy
        int exp_date;//expiry date of policy
        float ins_prem;//premimum for the policy
public:
        MainIns();//default constructor, used to instantiate the object
        ~MainIns();//Destructor
                //Accessors
                int getPolNum();
                string getPolHol();
                int getEffDate();
                int getExpDate();
                float getInsPrem();
               
                        //Mutators
                        void setPolNum(int);
                        void setPolHol(string);
                        void setEffDate(int);
                        void setExpDate(int);
                        void setInsPrem(float);
};

#endif

---

Code:

---

#ifndef Life_Insurance_Header
#define Life_Insurance_Header
#include "Life_Insurance_Header.h"

class LifeIns{
        string per_name;
        int per_age;
        string fl_address;
        string sl_address;
        string occupation;
        friend MainIns insurance(MainIns &);

public:
        LifeIns();//constructor
        ~LifeIns();//destructor
                //Accessors
                string getPerName();
                int getPerAge();
                string getFLAdress();
                string getSLAdress();
                string getOccupation();
               
                //Function to initialize attributes of MainIns for LifeIns
                MainIns insurance (MainIns ins);
                       
                        //Mutators
                        setPerName(string);
                        setPerAge(int);
                        setFLAdress(string);
                        setSLAdress(string);
                        setOccupation(string);
       




#endif

---

Hmm, inheritance is there to share and extend interfaces between objects. So instead of a Life Insurance type containing a Insurance type, you would borrow from and extend your Insurance type's interface. In that way, you are implementing Life Insurance in terms of the more general type.

So say I had:

Code:

---

class Insurance {
  protected:
    int dateExpired;
    int dateEffective;
    string policyNumber;
    string policyHolder;

  public:
    Insurance();
    vitual ~Insurance();
    // etc...
};

---

With piblic inheritence we can take this general object, it's methods and it's data members, and make it something more useful.

Code:

---

class LifeInsurance: public Insurance {
  // Life Insurance only stuff here...
  public:
    LifeInsurance(); // build an Insurance object first, Life insurance specific stuff built on top of that
  // the interface here...
};

---

That's the basic idea. Life insurance would inherit from the base class the methods you implemented earlier and in Life Insurance, we could add data, like their occupation, and methods to use or expose that data to the rest of the program.

Quote:

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Originally Posted by whiteflags

Code:

---

class LifeInsurance: public Insurance {
  // Life Insurance only stuff here...
  public:
    LifeInsurance(); // build an Insurance object first, Life insurance specific stuff built on top of that
  // the interface here...
};

---

That's the basic idea. Life insurance would inherit from the base class the methods you implemented earlier and in Life Insurance, we could add data, like their occupation, and methods to use or expose that data to the rest of the program.

---

ok that code there was giving me a thinking but i kinda understand it now. The question asked for like a type of policy so i thought the different polices would be the general class and inherit everything from the main insurance class, but what u put up awhile ago put my idea on the back bench....Thanks. When i start having problems with the implementation I post here too ok.

Code:

---

int pol_num;//policy number
string pol_hol;//policy holder
int eff_date;//effective date of policy
int exp_date;//expiry date of policy
float ins_prem;//premimum for the policy

---

Code:

---

string per_name;
int per_age;
string fl_address;
string sl_address;
string occupation;

---

may be you can put them into struct.... so it will be much more elegant...
:)

Code:

---

#ifndef Life_Insurance_Header
#define Life_Insurance_Header
#include "Life_Insurance_Header.h"

---

This looks a bit wrong. Either the include-guards are wrong, or you meant to include something else? Because to me, it looks like you are including the very same header file you were just in...

--
Mats

Quote:

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Originally Posted by matsp

Code:

---

#ifndef Life_Insurance_Header
#define Life_Insurance_Header
#include "Life_Insurance_Header.h"

---

This looks a bit wrong. Either the include-guards are wrong, or you meant to include something else? Because to me, it looks like you are including the very same header file you were just in...

--
Mats

---

i fixed that, but this what am doing is a work in progress for an oop class am doing at school. Here is the update to what i have now.

Code:

---

#ifndef Life_Insurance_Header
#define Life_Insurance_Header
#include "Insurance_header.h"
class LifeInsurance: public MainIns{
private:
        string per_name;
        int per_age;
        string fl_address;
        string sl_address;
        string occupation;
        int val_per;// estimate value of an object

public:
        LifeIns();//constructor
        ~LifeIns();//destructor
                //Accessors
                string getPerName();
                int getPerAge();
                string getFLAdress();
                string getSLAdress();
                string getOccupation();
                float getValPer();

                //Mutators
                void setPerName(string);
                void setPerAge(int);
                void setFLAdress(string);
                void setSLAdress(string);
                void setOccupation(string);
                void setValPer(float);
                //bool DoYouSmoke (LifeInsurance &);//Accepts an object and returns true or false if the policy holder is a smoker or not
                //void AccDeathDismenCov (LifeInsurance &);//Accepts an object checks if the client needs accidental death and dismenberment coverage
                float calPremium(float);//Function that accepts the value of the person to be insured to calculate the premium of the person



};
               

#endif

---

Code:

---

#ifndef MotorVehicle_Insurance_header
#define MotorVehicle_Insurance_header
#include "Insurance_Header.h"


class MotVehicle_Ins: public MainIns {
private:
        string veh_mod;
        string veh_make;
        int year;
        int license_num;
        int chasis_num;
        float est_veh_val;
        string fuel_type;
        string body_type;
        int cc_rating;
        int seat_cap;
        string owner;
       

public:
                MotVehicle_Ins();
                ~MotVehicle_Ins();       
       
                //Accessors
                string getVehMod();
                string getVehMake();
                int getYear();
                int getChasisNum();
                int getLicenseNum();
                float getEstVehVal();
                string getFuelType();
                string getBodyType();
                int getCCRating();
                int getSeatCap();
                string getOwner();

                //Mutators
                void setVehMod(string);
                void setVehMake(string);
                void setYear(int);
                void setChasisNum(int);
                void setLicenseNum(int);
                void setEstVehVal(float);
                void setFuelType(string);
                void setBodyType(string);
                void setCCRating(int);
                void setSeatCap(int);
                void setOwner(string);

               

                //bool AccidentPrevYear(MotVehicle_Ins &);
                //bool BurgularAlarm(MotVehicle_Ins &);
                float CalculatePrem (float);//Accepts the value of the car then calculates the premium depending on certain criteria then returns a float



};
#endif

---

Code:

---

#ifndef Insurance_header
#define Insurance_header
#include "Date.h"
#include <string>
//Parent Class
class MainIns: public Date {
private:
        int pol_num;//policy number
        //string pol_hol;//policy holder
        int eff_date;//effective date of policy
        int exp_date;//expiry date of policy
        float ins_prem;//premimum for the policy
public:
        MainIns();//default constructor, used to instantiate the object
        ~MainIns();//Destructor
                //Accessors
                int getPolNum();
                //string getPolHol();
                int getEffDate();
                int getExpDate();
                float getInsPrem();
               
                        //Mutators
                        void setPolNum(int);
                        //void setPolHol(string);
                        void setEffDate(int);
                        void setExpDate(int);
                        void setInsPrem(float);
};

#endif

---

Code:

---

#ifndef Insurance_header
#define Insurance_header
#include "Date.h"
#include <string>
//Parent Class
class MainIns: public Date {
private:
        int pol_num;//policy number
        //string pol_hol;//policy holder
        int eff_date;//effective date of policy
        int exp_date;//expiry date of policy
        float ins_prem;//premimum for the policy
public:
        MainIns();//default constructor, used to instantiate the object
        ~MainIns();//Destructor
                //Accessors
                int getPolNum();
                //string getPolHol();
                int getEffDate();
                int getExpDate();
                float getInsPrem();
               
                        //Mutators
                        void setPolNum(int);
                        //void setPolHol(string);
                        void setEffDate(int);
                        void setExpDate(int);
                        void setInsPrem(float);
};

#endif

---

Code:

---

#include "Date.h"
#include<iostream>
using namespace std;
Date :: Date()
{
        day=1;
        month=1;
        year=1;
}
Date :: Date(int d, int m, int y)
{
                day= d;
                month= m;
                year= y;
       
}

void Date:: setDate1(int d, int m, int y)
{
        day= d;
        month= m;
        year= y;
}

int Date :: getDay()const
{
        if (day>=1 && day<=31){
        return day;
        }//end if
}// ends fucntion

int Date :: getMonth() const
{
        if(month>=1 && month<=12)
        {
                return month;
        }//end if
}//ends function

int Date :: getYear() const
{
        return year;
}

---

Remember in the main insurance i had effect date attributes and expiry date, instead of using those i inserted a date interface where i can use that to intialize those dates. I cant wait to finish this so i can feel pleased within my self as a beginner programmer.

in header file you should not use using directive - so you should use fullyqualified types like

std::string instead of just string

Quote:

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Originally Posted by vart

in header file you should not use using directive - so you should use fullyqualified types like

std::string instead of just string

---

the code that i used the directive in was an implentation file for the date class. thanks for the string advice, thats why i was getting an error while debugging, thats y i also placed comments and any code segment with "string" going or returning from a function thanks.
why is it when declaring a string this has to be used before you put the variable name ";"?

Ok, once more I have come to a buck with some syntax and i think i have tried everything i kno to correct it so here goes the code and thanks for the help you guys been giving me so far.

Code:

---

#include<iostream>
#include"Vehicle_Header.h"
using std::string;
using namespace std;

Vehicle:: Vehicle(){

}
Vehicle:: Vehicle(Vehicle&){

}
Vehicle:: ~Vehicle(){

}
string Vehicle:: getVehMod(){
               
        return veh_mod;

}

string Vehicle:: getVehMake(){

        return veh_make;

}

int Vehicle:: getYear(){

        return  year;

}
         

int Vehicle:: getChassisNum(){

        return chassis_num;

}


int Vehicle:: getLicenseNum(){

                return license_num;

}
float Vehicle:: getEstVehVal(){

        return veh_val;

}


string Vehicle:: getFuelType(){

        return fuel_type;

}
       
string Vehicle:: getBodyType(){

        return body_type;

}

int Vehicle:: getCCRating(){

        return cc_rating;
       
}

int Vehicle:: getSeatCap(){

        return seat_cap;

}

string Vehicle:: getOwner(){

        return  owner;

}

void Vehicle:: setVehMod(string model){
               
        string veh_mod= model;

}
       
       
       
       

       
       
       

        void Vehicle:: setVehMake(string make){

       
                string veh_make= make;

        }
        void Vehicle:: setYear(int veh_year){
               
                int year= veh_year;

        }
        void Vehicle:: setChassisNum(int chassis){

                int chassis_num= chassis;

        }
                  void Vehicle:: setLicenseNum(int license){

                          int license_num= license;

          }
                  void Vehicle:: setEstVehVal(float value){

                          veh_val= value;

                  }

                  void Vehicle:: setFuelType(string fuel){

                          string fuel_type= fuel;

                  }


                  void Vehicle:: setBodyType(string body){

                          string body_type= body;

                  }
                  void Vehicle:: setCCRating(int rating){
                         
                                int cc_rating= rating;

                  }
                  void Vehicle:: setSeatCap(int capacity){

                          int seat_cap= capacity;

                  }


                  void Vehicle:: setOwner(string own){

                          string owner= own;

                  }

          //void Vehicle:: ShowClientDetails(Client&)
                  bool Vehicle:: Burlar_Alarm(void){
                       
                                 
        bool bur_alarm;
       
                  }
       
       
bool Vehicle:: Any_Accident(void){
                string accident;
                string no_accident;
                cout<<"\nHas The Vehicle Been through any accidents?"<<"\nYes/No:";
                cin>> accident;
                        if (accident= "yes" && "Yes"){
                                return 1;
                        }
                        else
                                return 0;
                       

               
}

---

here are the errors: vehicle_implimentation.cpp(163) : error C2451: conditional expression of type 'std::basic_string<_Elem,_Traits,_Ax>' is illegal
2. binary '>>' : no operator found which takes a right-hand operand of type 'std::string' (or there is no acceptable conversion)

Is there an include for <string> somewhere?

--
Mats

ok i got rid of 2 of the problems , i only have a condional error now. i think its my if statement that is the problem. gonna continue fishing around it to see if i can get rid of the problem...

Code:

---

if (accident= "yes" && "Yes"){

---

Is definitely not right (I thought I edited that into the previous post, but apparently not). I'm not sure that is what the "conditional" is about, quite possibly.

--
Mats

error C2677: binary '||' : no global operator found which takes type 'std::string' (or there is no acceptable conversion)

when i get this error what am i facing?

Quote:

---

Originally Posted by frassunit

error C2677: binary '||' : no global operator found which takes type 'std::string' (or there is no acceptable conversion)

when i get this error what am i facing?

---

Can you post a line or three around that?

It sounds like you are doing || with one side as a string - which would be a rather strangt thing to do.

--
Mats

Code:

---

bool Vehicle:: Any_Accident(void){
                string accident;
               
                cout<<"\nHas The Vehicle Been through any accidents?"<<"\nYes/No:";
                cin>> accident;
                        if (accident== "yes" || accident== "Yes"){


                                return 1;
                        }
                        else
                                return 0;
                       

               
}

---

OK the error was gone when i used two equal signs cuz i forgot that what am doing is something similar to strcmp...

Code:

---

                        if (accident== "yes" || accident== "Yes"){


                                return 1;
                        }
                        else
                                return 0;

---

Why is there braces around the return in the if-side, but not braces in the else-side?

--
Mats

Quote:

---

Originally Posted by matsp

Why is there braces around the return in the if-side, but not braces in the else-side?

---

Glad I'm not the only one who gets annoyed by dangling else statements! Personally I always use braces, even if it's a one-liner, but at the very least be consistent for both if and else case!

QuantumPete