Invalid arguments when calling getter member

Question

The error happen when I try to use one of my get function on parameter inside member functions. The error is:

Invalid arguments '. Candidates are : int getTotalArea() .

here is an example from my code :

        class Apartment{
    public : // ...
enum SquareType {EMPTY, WALL, NUM_SQUARE_TYPES};

        bool operator<(const Apartment& apartment); // done - need help

        int getTotalArea(); // done

        private:
        int price;
        int length;
        int width;
        SquareType** squares;

    };


    int Apartment::getTotalArea()
    {
        int count=0;
        for(int i=0;i<width;i++)
        {
            for(int j=0;j<length;j++)
            {
                if(squares[i][j]==EMPTY)
                {
                        count++;
                }
            }
        }
        return count;
    }

    bool Apartment::operator<(const Apartment& apartment)
    {
        int thisArea=this->getTotalArea();
        int paramArea=apartment.getTotalArea(); // the error line is here !!!
//the error is Invalid arguments '. Candidates are : int getTotalArea() .
        double thisRatio=((double)price)/thisArea;
        double paramRatio=((double)apartment.price)/paramArea;
        if(thisRatio==paramRatio)
        {
            return price < apartment.price;
        }
        return thisRatio<paramRatio;

    }

Have I done something wrong ?

It's the first time I'm using c++ ... by the way - any comments for the rest of the code are fine as well.

If you have errors you should share them. It is not nice to horde the errors. — NathanOliver, Jun 09 '16 at 12:15
tell us the error so we can help and post just the code where the errors happens. We cant read your whole code. — kemis, Jun 09 '16 at 12:16
Please consider posting a [Minimal, Complete, and Verifiable example](http://stackoverflow.com/help/mcve). — MikeCAT, Jun 09 '16 at 12:17
I edited the comment - the error happen when i try to use one of my get function on parameter inside member functions. the error is Invalid arguments ' . — Omer Eliyahu, Jun 09 '16 at 12:19
@OmerEliyahu copy and paste the actual error message into the question. — NathanOliver, Jun 09 '16 at 12:20
Your example is not *Complete* because `SquareType` and `EMPTY` aren't defined. — MikeCAT, Jun 09 '16 at 12:23
Just comment "for the rest of code": do not use `if(thisRatio==paramRatio)` when `thisRatio` and/or `paramRatio` are `float` or `double`, use `<=` or `<` and consider applying some delta to compare difference between `thisRatio` and `paramRatio` — VolAnd, Jun 09 '16 at 12:23
I have edited the whole post , the problem is to use getTotalArea() in member functions. — Omer Eliyahu, Jun 09 '16 at 12:27
@OmerEliyahu `int getTotalArea();` is missing a `const`: `int getTotalArea() const;` — πάντα ῥεῖ, Jun 09 '16 at 12:43

score 2 · Answer 1 · edited May 23 '17 at 11:58

2

From the answer of PcAF seems you've heavily changed your initial post without modifying your question. Very bad!

However, the problem you're facing now with getTotalArea is that it isn't declared const.

See https://stackoverflow.com/a/751690/781933 for explanation.

edited May 23 '17 at 11:58

Community

1
1

answered Jun 09 '16 at 12:37

rfb

1,107
1
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14

Still i can't understand why my code cannot go through compilation. the compiler know if I dont change anything and force me to declare it as const ? – Omer Eliyahu Jun 09 '16 at 12:59

PcAF · Answer 2 · 2016-06-09T12:26:15.773

1

Seems like you misunderstood operator overloading (as members)

When overloading some operator as member, then first operand of that operator is object on which member operator overload is called and second operand is parameter to that function (in case of binary operators).

operator + can be used as binary(2 operands) or unary operator(1 operand).

Here it seems like you want to overload binary version as member:

Apartment operator+(const Apartment& apartment1,const Apartment& apartment2);

but since first operand is object on which that member "function" is called it must take only 1 parameter (which is second operand).

Apartment operator+(const Apartment& apartment2);

Here is the second mistake:

Apartment& operator=(SquareType** squares, int length, int width, int price);

operator = is binary operator (2 operands), therefore if you want to overload it as member function it has to take exactly one parameter (which is second operand of =), not 4 parameters.

edited Jun 09 '16 at 12:26

answered Jun 09 '16 at 12:23

PcAF

1,975
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i know that , I removed it from the class . It's non member operand anymore. – Omer Eliyahu Jun 09 '16 at 12:26
1

I've updated my answer, also I recommend you to learn something about *operator overloading*, because it seems that you don't quite understand it. – PcAF Jun 09 '16 at 12:31
Thank you for your help . do you have any idea about the error that I got ? – Omer Eliyahu Jun 09 '16 at 12:38

Invalid arguments when calling getter member

2 Answers2