Question

Just learning Classes in C++, I thought I had a fairly good grip on it but for some reason this code won’t even compile.

#include <iostream>
#include <cstdlib>

using namespace std;

class Position
{
    int row;
    int column;
public:
    Position();         //constructor
    ~Position();        //destructor
    void setPos(int, int);  //set the position
    int getRow();       //return the current row
    int getColumn();    //return the current column
    void getPos();      //print the pos
    bool compare(int, int); //compare a row and column with the one in the class
};

Position::Position()
{}
Position::~Position()
{}
void Position::setPos(int x, int y)
{
    Position.row = x;
    Position.column = y;
}
int Position::getRow()
{
    return Position.row;
}
int Position::getColumn()
{
    return Position.column;
}
void Position::getPos()
{
    cout << "Row: " << Position.row << "Column: " << Position.column;
}
bool Position::compare(int x, int y)
{
    if(x == Position.row && y == Position.column)
        return true;
    else
        return false;
}

Running this code straight in MS Visual Studio 2010 yields these compiling problems:

...prob2.cpp(30): error C2143: syntax error : missing ';' before '.'
Line 30 is: Position.row = x;
I don’t see why or where there should be a ; anywhere there.

I get this error on several other lines including the one right under it.

I should note that I don’t have a main function although I don’t think this is needed.

Answer 1

You don’t need to prefix instance variables using the class name, instead use row or this->row

EDIT:

Eventually you will want to move the class declaration to a header file ie. position.h and keep the implementation in the position.cpp file with #include "position.h" at the top. This will make your Position class usable in other files.