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Derivative class does not work.

pische (2)
Hi all, I'm trying to write a little program that makes use of derived classes but it doesn't work and I don't know why. It's not very meaningful, it just does some monitor printing. Just to figure out how to connect the various .h and .cpp files.
Can you help me? Thanks

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ifndef ROBOT_H_INCLUDED
#define ROBOT_H_INCLUDED

class Robot{  // Class base
public:
void MoveForward(); //Procedure
};

#endif // ROBOT_H_INCLUDED

************************************
#include <iostream>  
#include "Robot.h"

using namespace std;

void Robot::MoveForward()
{
    cout << "MoveForward" << endl;
}
*************************************
#ifndef SENSOR_H_INCLUDED
#define SENSOR_H_INCLUDED


class Sensor : public Robot //Sensor is derived from Robot
{
public:
    void MPU6050(); //Procedure
    Robot.MoveForward(); //Class base ERROR!
};
#endif // SENSOR_H_INCLUDED

**********************************
#include <iostream>
#include "Sensor.h"

using namespace std;

void Sensor::MPU6050()
{
    cout << "MPU6050" << endl;
}
***********************************

#include <iostream>
#include "Robot.h"
#include "Sensor.h"
using namespace std;

int main()
{
    Sensor s;
    s.MPU6050();
//  s.MoveForward(); Shouldn't he inherit from Robot? He won't let me.
    return 0;
}
Last edited on
mbozzi (3911)
Remove line 30.
Uncomment line 55. (But comment the English text on that line)

This program is tiny. Except for the purposes of teaching, there's not a pressing need to split everything up into files.
Last edited on
Repeater (3046)
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class Sensor : public Robot //Sensor is derived from Robot
{
public:
    void MPU6050(); //Procedure
    Robot.MoveForward(); //Class base ERROR!
};


That line in bold. It makes no sense at all.

Here is working code:
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#include <iostream>

using namespace std;

class Robot{  // Class base
public:
void MoveForward(); //Procedure
};

void Robot::MoveForward()
{
    std::cout << "MoveForward" << endl;
}

class Sensor : public Robot //Sensor is derived from Robot
{
public:
    void MPU6050(); //Procedure
};

void Sensor::MPU6050()
{
    cout << "MPU6050" << endl;
}

int main()
{
    Sensor s;
    s.MPU6050();
    s.MoveForward();
    return 0;
}
ne555 (10692)
> Sensor is derived from Robot
that makes no sense.

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    Sensor s;
    s.MoveForward();

that makes no sense.
dictionary wrote:
sensor
<hardware> An electronic device used to measure a physical quantity such as temperature, pressure or loudness and convert it into an electronic signal of some kind (e.g a voltage).
againtry (2313)
Some sensor units encapsulate/report/modify their position and direction independent of the robot they might be mounted on.
mbozzi (3911)
Public inheritance models specialization. As such, publicly deriving Sensor from Robot indicates that a Sensor is a specialized kind of Robot, which is probably nonsense in a typical model

Instead it is more likely that a Robot is associated with or contains one or more Sensors.
Last edited on
againtry (2313)
Yawn!
pische (2)
Thank you! You're right, the program is tiny because I have to learn. Splitting the file into several files was how I needed to figure out how to connect them. In the future I could have many classes each with its own .h and a .cpp.I wrote this example program that doesn't make much sense, of course, just to understand how to connect the various files because around the network I have not found anything like that.
Thanks again and Happy New Year! :)
pische
againtry (2313)
:)
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