Error - Call to non-static member function...

[PaulP308]

I was able to find and resolve most of my errors in this program. But I have 4 bugs left, all the same error message "Call to non-static member function without argument". What am I missing or doing wrong?

These are the lines effected:
string getMonthName()
{
return monthName[ Date::getMonth() + 1 ];
} // end of getMonthName function

void displayNumericDate()
{
cout << setfill( '0') << setw( 2 ) << Date::getDay() << "/"
<< setfill( '0') << setw( 2 ) << Date::getMonth()<< "/" << setw( 4 ) << Date::getYear()
} // end of displayNumericDate function

void displayLongDate()
{
cout << Date::getDay() << " " << getMonthName() << ", " <<Date::getYear()
} // end of displayLongDate

Thank you for your assistance

[laserlight]

You might want to post the Date class definition. I'm assuming that these function definitions are within the Date class definition, but with what you posted we have to guess as to what really is a member, what isn't; what really is a static member, what isn't.

Also, please post code in [code][/code] bbcode tags.

[PaulP308]

Thank you, I was looking for that.

Header file

//
//  Date.h
//  Date class with constructor with default arguments
//  Member functions defined in Date.cpp
//  C++ Programming
//  Fall 2014
//  Paul Peterson
//
//

#ifndef ____Date__
#define ____Date__

#include <iostream>
#include <iomanip>
#include <string>
using namespace std;

class Date
{
public:

    // default constructor setting date to January 1, 2000
    explicit Date ( int = 1, int = 1, int=2000 );
    
    // set functions
    // function to set date
    void setDate( int, int, int ); //set date DD/MM/YYYY
    
    // function to set day
    void setDay( int );  //set day
    
    // function to set month
    void setMonth( int ); // set month
    
    // function to set month name
    void setMonthName(string);  // set month name
    
    // function to set year
    void setYear( int); // set year
    
    // get functions
    
    // function to return the day value of the class Date
    int getDay() const; // return day value

    // function to return the month value of the class Date
    int getMonth() const; //return month value
    
    // function to get month Name
    string getMonthName() const; // return the name of the month
    
    // function to return the year value of the class Date
    int getYear() const; // return year value

    // function to display Date in DD/MM/YYYY format including leading 0 where needed
     void displayNumericDate() const;
   
    // function to display date in long date eg. 1 January, 1900
    void displayLongDate() const;
    
private:
    
    int month;
    int day;
    int year;

};  // end of class Date

#endif /* defined(____Date__) */

___________________________________________________

Member Functions:

// Date.cpp
//
// C++ Programming
// Fall 2014
// Paul Peterson

#include <iostream>
#include <iomanip>
#include <string>
#include <array>

using std::cout;
using std::endl;
using std::setfill;
using std::setw;
using std::string;
using namespace std;

#include "Date.h"

array < int, 12> numberOfDays = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
array < string, 12> monthName = { "January", "February", "March", "April", "May",
    "June", "July", "August", "September", "October", "November", "December"};

// Date constructor with arguments and validation
Date::Date( int day, int month, int year)
{
    setDate( day, month, year ); //validate and set date
}  // end Date constructor

// set date value
void Date::setDate( int d, int m, int y)
{
    setDay( d ); // get private field day
    setMonth( m ); //get private field month
    setYear( y ); // get private field year
}  // end function setDate

void Date::setDay ( int d)
{
    if ( d >= 1 && d <= numberOfDays[ month - 1] )
        day = d;
    else
        day = 1;
} // end of setDay function

void Date::setMonth (int m)
{
    if ( m >=1 && m <= 12 )
        month = m;
        else
            month = 1;
            }  // end of setMonth function

void Date::setYear(int y)
{
    if ( y >= 1900 )
        year = y;
    else
        year = 1900;
}  // end of setYear function

// return day value
int Date::getDay() const
{
    return day;
} // end of getDay function

// return month value
int Date::getMonth() const
{
    return month;
} // end of getMonth function

// return the month name
string getMonthName()
{
    return monthName[ Date::getMonth() + 1 ];
} //

// return year value
int Date::getYear() const
{
    return year;
} // end of getYear function

// print date in DD/MM/YYYY format
void displayNumericDate()
{
    cout << setfill( '0') << setw( 2 ) << Date::getDay() << "/"
    << setfill( '0') << setw( 2 ) << Date::getMonth()<< "/" << setw( 4 ) << Date::getYear()
}  // end of displayNumericDate function

// print date in long date format eg. 1 January, 1900
void displayLongDate()
{
    cout << Date::getDay() << " " << getMonthName() << ", " <<Date::getYear()
}  // end of displayLongDate

[laserlight]

Ah. You forgot to prefix the member function definitions will the class name, e.g.,

string getMonthName()
{
    return monthName[ Date::getMonth() + 1 ];
}

should have been:

string Date::getMonthName()
{
    return monthName[ Date::getMonth() + 1 ];
}

Note that within this member function definition, you don't have to write Date::getMonth() since there is no ambiguity to resolve. You can just write getMonth().

[laserlight]

A few other things to note:

• Change your header inclusion guard macro name too, e.g., use PaulP308_DATE_H instead of ____Date__.
• Do not use using directives like using namespace std; or using declarations like using std::string at file scope in header files. Rather, fully qualify those names in the header file.
• Do not #include files after using directives or using declarations. I noticed that you did this in the source file.
• Your Date class definition only depends on std::string, so you only need to #include <string>. Move #include <iostream> and #include <iomanip> to the source file.
• numberOfDays and monthName in the source file should be declared const. Furthermore, you should declare them within an unnamed namespace because they are implementation details specific to that source file.
• If you declare a member function as const in the class definition, then you should declare it as const when you define the member function. An example of such a discrepancy is your displayNumericDate member function.
• Personally, I would remove the "end of foo function" comments. The indentation should already give a visual indication of where the function starts and ends, and if it doesn't, then the function is probably too long and should be broken up into smaller functions that do one thing and do it well.

[PaulP308]

Thank you for that. That did clear the initial error code, but now I'm getting the an error stating "Out-of-line definition of 'getMonthName' does not match any declaration in 'Date'.

[laserlight]

That is because getMonthName is yet another example of the const member function discrepancy that I mentioned in post #5.

[2kaud]

numberOfDays and monthName in the source file should be declared const. Furthermore, you should declare them within an unnamed namespace because they are implementation details specific to that source file.

As numberOfDays and monthName are used only by Date class functions, I would consider having them as private static const members of the date class.

You can also shorten some of your code. eg

void Date::setMonth (int m)
{
    if ( m >=1 && m <= 12 )
        month = m;
        else
            month = 1;
            }  // end of setMonth function

can be replaced by

void Date::setMonth(int m)
{
     month = (m >=1 && m <= 12) ? m : 1;
}

return monthName[ Date::getMonth() + 1 ];

Are you sure this should be +1 ?

[PaulP308]

Thank you for both suggestions, and no, that should be Date::getMonth() - 1

[PaulP308]

Thank you again.

Please bear with me, as you can tell, I am a student and a little overwhelmed at the moment, working full time, have a second part time job, a family of 5 who keep me very busy and taking three programming classes this semester. This is the first assignment and I am a little lost with your comments.

Change your header inclusion guard macro name too, e.g., use PaulP308_DATE_H instead of ____Date__.

is the actual format of the "PaulP308..." important or can I use something that fits with the course or my name?

Do not use using directives like using namespace std; or using declarations like using std::string at file scope in header files. Rather, fully qualify those names in the header file.

sorry for being a bit obtuse, can you dumb that down a little please.

[PaulP308]

Do not #include files after using directives or using declarations. I noticed that you did this in the source file.

talking about the "#include "Date.h"? I should move that up with the other #include statements, right?

numberOfDays and monthName in the source file should be declared const. Furthermore, you should declare them within an unnamed namespace because they are implementation details specific to that source file.

Not sure what you mean by "unnamed namespace". I originally had all of the functions declared as const, but was getting error messages saying to delete the const.

If you declare a member function as const in the class definition, then you should declare it as const when you define the member function. An example of such a discrepancy is your displayNumericDate member function.

add const to the function prototype in the class file as well as the source file, right?

As for the end of foo function comments, following the format of the text book. I thought it was a little excessive too, but until I see how the instructor grades I will probably leave them, for now. I thought it was a little much to put an end of function with only one or two lines in the function.

Please forgive me for asking so many questions today. Just trying to make it through the next week, hopefully things will calm down a little after the race Saturday ("running" my first 1/2 marathon). After Saturday I won't heve quite the sense of urgency to make as much time for running.

[PaulP308]

This what you had in mind?

// print date in DD/MM/YYYY format
void Date::displayNumericDate()
{
    cout << setfill( '0' ) << setw( 2 ) << getDay() << "/"
    << setfill( '0') << setw( 2 ) << getMonth()<< "/" << setw( 4 ) << getYear();
}  // end of displayNumericDate function

// print date in long date format eg. 1 January, 1900
void Date::displayLongDate()
{
    cout << getDay() << " " << getMonthName() << ", " << getYear();
}  // end of displayLongDate

[laserlight]

is the actual format of the "PaulP308..." important or can I use something that fits with the course or my name?

It has to be a valid identifier. ____Date__ is a valid identifier, but it is reserved to the implementation (compiler/standard library) since names that begin with an underscore followed by another underscore or an uppercase letter, or names that contain consecutive underscores, are reserved to the implementation. You could just use DATE_H, but since these names must be unique, using a special prefix or having a timestamp suffix are some of the approaches to ensure that the name is unique.

sorry for being a bit obtuse, can you dumb that down a little please.

In other words, instead of having this in the header file:

using namespace std;

// ...

    string getMonthName() const;

Just write:

    std::string getMonthName() const;

talking about the "#include "Date.h"? I should move that up with the other #include statements, right?

Yes.

add const to the function prototype in the class file as well as the source file, right?

Yes.

As for the end of foo function comments, following the format of the text book. I thought it was a little excessive too, but until I see how the instructor grades I will probably leave them, for now. I thought it was a little much to put an end of function with only one or two lines in the function.

I certainly find them excessive. A problem with comments is that they must be updated otherwise they will cause confusion instead of help in understanding the code, but because the compiler and testing tools ignore them, they are less likely to be correctly updated than the code itself. Therefore, it makes sense not to write comments that state things that should be obvious even to a reader who is not expert and/or familiar with the code base (but who knows how to program).

This what you had in mind?

Close, but you still need the const-ness of the member functions to match what you declared in the class definition.

[2kaud]

Please bear with me, as you can tell, I am a student and a little overwhelmed at the moment, working full time, have a second part time job, a family of 5 who keep me very busy and taking three programming classes this semester. This is the first assignment and I am a little lost with your comments.

Welcome! We are a friendly bunch who'll provide advice and guidance. Have you read
http://forums.codeguru.com/showthrea...ork-assignment

A comment re your header files. You have statements like

explicit Date ( int = 1, int = 1, int=2000 );

which whilst valid (only the definition needs to have the parameter names) do very little to inform the user of the header file regarding the purpose of the parameters. I know some textbooks show it like this (and some teachers also show it this way) but IMO I would specify meaningful parameter names in the declaration so that someone looking only at the header gets some idea as for what the parameters are used. eg

explicit Date (int day = 1, int month = 1, int year = 2000);