Can you initialize arrays in the class declaration

**Calef13** · 02-23-2008

Hi,

I am writing a simple chat program using Qt4. I decided to convert all text which is sent over the network into morse code as a side task to better understand string manipulation. I am having problems compiling now though. This is my first OO program and I decided to put the two arrays I use for conversion in the class header as private. I have other variables in the header file, but I had to make them const static to stop the compiler complaining. However the compiler still gives me errors with the arrays, they are below

Code:

In file included from kether.cpp:6:
kether.h:40: error: a brace-enclosed initializer is not allowed here before ‘{’ token
kether.h:66: error: invalid in-class initialization of static data member of non-integral type ‘const char [26][6]’
kether.h:67: error: a brace-enclosed initializer is not allowed here before ‘{’ token
kether.h:68: error: invalid in-class initialization of static data member of non-integral type ‘const char [26]

Here is the relevant section from the header file

Code:

public slots:
        QString morseToText(QString morseCode);
        QString textToMorse(QString message);
        void on_ipConnect_clicked();
        void on_ipDisconnect_clicked();
        void on_ipAddress_textEdited();
        void on_sendMessage_clicked();
        void on_messageEntry_textEdited(QString message);
        void on_listen_clicked();
        void readData();
        void reportDisconnect();
        void connectedToHost();
        void handleNewConnection();
    private:
        Ui::kether ui;

        QTcpSocket *tcpSocket;
        QTcpServer *tcpServer;

        const static quint16 port = 9001;
        qint64 oneByte;
        char endOfCharacter;
        const static char morse[26][6] = {{'.','-','\0'}, //a
                            {'-','.','.','.','\0'}, //b
                            {'-','.','-','.','\0'}, //c
                            {'-','.','.','\0'}, //d
                            {'.','\0'}, //e
                            {'.','.','-','.','\0'}, //f
                            {'-','-','.','\0'}, //g
                            {'.','.','.','.','\0'}, //h
                            {'.','.','\0'}, //i
                            {'.','-','-','-','\0'}, //j
                            {'-','.','-','\0'}, //k
                            {'.','-','.','.','\0'}, //l
                            {'-','-','\0'}, //m
                            {'-','.','\0'}, //n
                            {'-','-','-','\0'}, //o
                            {'.','-','-','.','\0'}, //p
                            {'-','-','.','-','\0'}, //q
                            {'.','-','.','\0'}, //r
                            {'.','.','.','\0'}, //s
                            {'-','\0'}, //t
                            {'.','.','-','\0'}, //u
                            {'.','.','.','-','\0'}, //v
                            {'.','-','-','\0'}, //w
                            {'-','.','.','-','\0'}, //x
                            {'-','.','-','-','\0'}, //y
                            {'-','-','.','.','\0'} //z
        };
        const static char lookup[26] = {'a','b','c','d','e','f','g','h','i','j','k','l','m'
                          ,'n','o','p','q','r','s','t','u','v','w','x','y','z'};

Additionally, the compiler claims none of the variables used in the two morseCode functions have been declared even though some of them are used elsewhere in the program without problems (Ui::kether ui). This is pretty confusing as the functions are members of the class as seen above. The errors and the functions are below

Code:

kether.cpp: In function ‘QString morseToText(QString)’:
kether.cpp:147: error: ‘endOfCharacter’ was not declared in this scope
kether.cpp:158: error: ‘ui’ was not declared in this scope
kether.cpp:160: error: ‘morse’ was not declared in this scope
kether.cpp:167: error: ‘lookup’ was not declared in this scope
kether.cpp: In function ‘QString textToMorse(QString)’:
kether.cpp:183: error: ‘lookup’ was not declared in this scope
kether.cpp:186: error: ‘morse’ was not declared in this scope
kether.cpp:191: error: ‘endOfCharacter’ was not declared in this scope

Code:

QString morseToText(QString morseCode)
{
    QString message;
    int k,lastmarker,counter = 0;
    for(int j = 0;j < morseCode.size();j++)
    {
        while((k = morseCode.indexOf(endOfCharacter, k)) != -1)
        {
            QString character;
            for(int l = lastmarker;l < k; l++)
            {
                character = morseCode[l];
            }
            for(int m = 0; m < character.size();m++)
            {
                if(counter > 25)
                {
                    ui.chatWindow->append("Decoding of message failed, this should never happen.");
                }
                else if(character[m] != morse[counter][m])
                {
                    counter++;
                    m = 0;
                }
                else if(morse[counter][m] == NULL)
                {
                    message.append(lookup[counter]);
                }

            }
            k++;
        }
    }
}

QString textToMorse(QString message)
{
    QString morseCode;
    for(int j = 0;j < message.size();j++)
    {
        for(int i = 0; i < 26; i++)
        {
            if(message[j] == lookup[i])
            {
                int k = 0;
                while(morse[i][k] != NULL)
                {
                    morseCode.append(morse[i][k]);
                    k++;
                }
                morseCode.append(endOfCharacter);
            }
        }
    }
}

I'm sorry for the length of this post, I tried to cut out as much irrelevant code as possible. I figure this is probably a very simple problem, but after reading through some websites about OO I can't see anything obvious. Any ideas?

**laserlight** · 02-23-2008

I believe the solution is:

In the class definition, declare:

Code:

const char lookup[26];

Then in the source file, implement:

Code:

const char Kether::lookup[26] = {'a','b','c','d','e','f','g','h','i','j','k','l','m'
                          ,'n','o','p','q','r','s','t','u','v','w','x','y','z'};

The same goes for the other static const array.

Additionally, the compiler claims none of the variables used in the two morseCode functions have been declared even though some of them are used elsewhere in the program without problems (Ui::kether ui). This is pretty confusing as the functions are members of the class as seen above. The errors and the functions are below

It looks like you did not qualify the member functions with the class name when implementing them, e.g.,

Code:

QString Kether::textToMorse(QString message)
{

**dwks** · 02-23-2008

Code:

                            {'.','\0'}, //e
                            {'.','.','-','.','\0'}, //f
                            {'-','-','.','\0'}, //g

There's really a much easier way to do that . . . .

Code:

                            ".", //e
                            "..-.", //f
                            "--.", //g

It's exactly the same thing.

String literals automatically add in a NULL terminator.

**Calef13** · 02-24-2008

Thanks for the replies. I'm still getting errors compiling after making the changes however

Code:

kether.cpp: In constructor ‘Kether::Kether(QWidget*)’:
kether.cpp:8: error: uninitialized member ‘Kether::morse’ with ‘const’ type ‘const char [26][6]’
kether.cpp:8: error: uninitialized member ‘Kether::lookup’ with ‘const’ type ‘const char [26]’
kether.cpp:14: error: invalid use of qualified-name ‘Kether::lookup’
kether.cpp:16: error: invalid use of qualified-name ‘Kether::morse’

I managed to get the 'uninitialized member' errors away by removing the const in the declarations in the header file, but even if I remove the ones in the source file as well the 'invalid' errors still persist. Thanks.

**vart** · 02-24-2008

Maybe I do not undestand your problem. Here is what I did:

test.h:

Code:

class test
{
	static const char arr[3][4] ;
public:
	test(void);
public:
	~test(void);
};

const char test::arr[3][4] = {"a", "bb", "ccc"};

test.cpp:

Code:

#include "test.h"
#include <iostream>

int main()
{
	test t;
}

test::test(void)
{
	std::cout << this->arr[0][0];
}

test::~test(void)
{
}

**Calef13** · 02-24-2008

Well, your test example above works fine for me. But when I declare the two arrays outside the class like yours I still get errors, and member functions apparently can't see them

Code:

In file included from kether.cpp:6:
kether.h:43: error: ‘const char Kether::morse [26][6]’ is not a static member of ‘class Kether’
kether.h:70: error: ‘const char Kether::lookup [26]’ is not a static member of ‘class Kether’
kether.cpp: In member function ‘QString Kether::morseToText(QString)’:
kether.cpp:202: error: ‘morse’ was not declared in this scope
kether.cpp:209: error: ‘lookup’ was not declared in this scope
kether.cpp: In member function ‘QString Kether::textToMorse(QString)’:
kether.cpp:226: error: ‘lookup’ was not declared in this scope
kether.cpp:229: error: ‘morse’ was not declared in this scope

I am using a few other programs when compiling my chat program(moc etc..) whereas I just used g++ for your test example could this be the problem?

Code:

#ifndef KETHER_H
#define KETHER_H
#include <QTcpSocket>
#include <QTcpServer>
#include <QString>
#include <QDate>

#include "ui_kether.h"

class QTcpSocket;
class QTcpServer;

class Kether : public QWidget
{
    Q_OBJECT

    public:
        Kether(QWidget *parent = 0);
    public slots:
        QString morseToText(QString morseCode);
        QString textToMorse(QString message);
        void on_ipConnect_clicked();
        void on_ipDisconnect_clicked();
        void on_ipAddress_textEdited();
        void on_sendMessage_clicked();
        void on_messageEntry_textEdited(QString message);
        void on_listen_clicked();
        void readData();
        void reportDisconnect();
        void connectedToHost();
        void handleNewConnection();
    private:
        Ui::kether ui;

        QTcpSocket *tcpSocket;
        QTcpServer *tcpServer;
        QDate todaysDate;
        QString dateFormat, logFileName;
        const static quint16 port = 9001;
        qint64 oneByte;
        char endOfCharacter;
};
    const char Kether::morse[26][6] = {{'.','-','\0'}, //a
                            {'-','.','.','.','\0'}, //b
                            {'-','.','-','.','\0'}, //c
                            {'-','.','.','\0'}, //d
                            {'.','\0'}, //e
                            {'.','.','-','.','\0'}, //f
                            {'-','-','.','\0'}, //g
                            {'.','.','.','.','\0'}, //h
                            {'.','.','\0'}, //i
                            {'.','-','-','-','\0'}, //j
                            {'-','.','-','\0'}, //k
                            {'.','-','.','.','\0'}, //l
                            {'-','-','\0'}, //m
                            {'-','.','\0'}, //n
                            {'-','-','-','\0'}, //o
                            {'.','-','-','.','\0'}, //p
                            {'-','-','.','-','\0'}, //q
                            {'.','-','.','\0'}, //r
                            {'.','.','.','\0'}, //s
                            {'-','\0'}, //t
                            {'.','.','-','\0'}, //u
                            {'.','.','.','-','\0'}, //v
                            {'.','-','-','\0'}, //w
                            {'-','.','.','-','\0'}, //x
                            {'-','.','-','-','\0'}, //y
                            {'-','-','.','.','\0'} //z
    };
    const char Kether::lookup[26] = {'a','b','c','d','e','f','g','h','i','j','k','l','m'
    ,'n','o','p','q','r','s','t','u','v','w','x','y','z'};
#endif

**vart** · 02-24-2008

AS error says - I do not see these two lines inside your class definition

Code:

static const char morse[26][6];
static const char lookup[26];

Do I miss them or you?

**Calef13** · 02-24-2008

Yeah sorry forgot those lines. I added them but then I get errors during linking as far as I can tell.

Code:

main.o:(.rodata+0x0): multiple definition of `Kether::morse'
kether.o:(.rodata+0x0): first defined here
main.o:(.rodata+0x9c): multiple definition of `Kether::lookup'
kether.o:(.rodata+0x9c): first defined here
moc_kether.o:(.rodata+0x40): multiple definition of `Kether::morse'
kether.o:(.rodata+0x0): first defined here
moc_kether.o:(.rodata+0xdc): multiple definition of `Kether::lookup'
kether.o:(.rodata+0x9c): first defined here

**vart** · 02-24-2008

you are missing /code in the closing tag

try to move array initialization into one of cpp files

**Calef13** · 02-24-2008

I moved it into the source file but then I get these errors

Code:

kether.cpp: In constructor ‘Kether::Kether(QWidget*)’:
kether.cpp:14: error: invalid use of qualified-name ‘Kether::lookup’
kether.cpp:16: error: invalid use of qualified-name ‘Kether::morse’

If I remove the 'Kether::' part from the initialization in the source file I get errors about undefined references.

**vart** · 02-24-2008

could you show the last code, because once again - just moving array initialization into cpp file - works fine for me

**Calef13** · 02-24-2008

Here is the header file and some of the source file, if you want to see more code just ask.

Code:

#ifndef KETHER_H
#define KETHER_H
#include <QTcpSocket>
#include <QTcpServer>
#include <QString>
#include <QDate>

#include "ui_kether.h"

class QTcpSocket;
class QTcpServer;

class Kether : public QWidget
{
    Q_OBJECT

    public:
        Kether(QWidget *parent = 0);
    public slots:
        QString morseToText(QString morseCode);
        QString textToMorse(QString message);
        void on_ipConnect_clicked();
        void on_ipDisconnect_clicked();
        void on_ipAddress_textEdited();
        void on_sendMessage_clicked();
        void on_messageEntry_textEdited(QString message);
        void on_listen_clicked();
        void readData();
        void reportDisconnect();
        void connectedToHost();
        void handleNewConnection();
    private:
        Ui::kether ui;

        QTcpSocket *tcpSocket;
        QTcpServer *tcpServer;
        QDate todaysDate;
        QString dateFormat, logFileName;
        const static quint16 port = 9001;
        qint64 oneByte;
        char endOfCharacter;
        static const char morse[26][6];
        static const char lookup[26];
};
 /*   const char Kether::morse[26][6] = {{'.','-','\0'}, //a
                            {'-','.','.','.','\0'}, //b
                            {'-','.','-','.','\0'}, //c
                            {'-','.','.','\0'}, //d
                            {'.','\0'}, //e
                            {'.','.','-','.','\0'}, //f
                            {'-','-','.','\0'}, //g
                            {'.','.','.','.','\0'}, //h
                            {'.','.','\0'}, //i
                            {'.','-','-','-','\0'}, //j
                            {'-','.','-','\0'}, //k
                            {'.','-','.','.','\0'}, //l
                            {'-','-','\0'}, //m
                            {'-','.','\0'}, //n
                            {'-','-','-','\0'}, //o
                            {'.','-','-','.','\0'}, //p
                            {'-','-','.','-','\0'}, //q
                            {'.','-','.','\0'}, //r
                            {'.','.','.','\0'}, //s
                            {'-','\0'}, //t
                            {'.','.','-','\0'}, //u
                            {'.','.','.','-','\0'}, //v
                            {'.','-','-','\0'}, //w
                            {'-','.','.','-','\0'}, //x
                            {'-','.','-','-','\0'}, //y
                            {'-','-','.','.','\0'} //z
    };
    const char Kether::lookup[26] = {'a','b','c','d','e','f','g','h','i','j','k','l','m'
    ,'n','o','p','q','r','s','t','u','v','w','x','y','z'};*/
#endif

Relevant part of the constructor:

Code:

    const char Kether::lookup[26] = {'a','b','c','d','e','f','g','h','i','j','k','l','m'
    ,'n','o','p','q','r','s','t','u','v','w','x','y','z'};
    const char Kether::morse[26][6] = {{'.','-','\0'}, //a
                            {'-','.','.','.','\0'}, //b
                            {'-','.','-','.','\0'}, //c
                            {'-','.','.','\0'}, //d
                            {'.','\0'}, //e
                            {'.','.','-','.','\0'}, //f
                            {'-','-','.','\0'}, //g
                            {'.','.','.','.','\0'}, //h
                            {'.','.','\0'}, //i
                            {'.','-','-','-','\0'}, //j
                            {'-','.','-','\0'}, //k
                            {'.','-','.','.','\0'}, //l
                            {'-','-','\0'}, //m
                            {'-','.','\0'}, //n
                            {'-','-','-','\0'}, //o
                            {'.','-','-','.','\0'}, //p
                            {'-','-','.','-','\0'}, //q
                            {'.','-','.','\0'}, //r
                            {'.','.','.','\0'}, //s
                            {'-','\0'}, //t
                            {'.','.','-','\0'}, //u
                            {'.','.','.','-','\0'}, //v
                            {'.','-','-','\0'}, //w
                            {'-','.','.','-','\0'}, //x
                            {'-','.','-','-','\0'}, //y
                            {'-','-','.','.','\0'} //z
    };

**laserlight** · 02-24-2008

Those are static const arrays. They are initialised outside of the constructor, in this case in the source file (without the static keyword). So it looks like you just need to take them out of the constructor.

Thread: Can you initialize arrays in the class declaration

Thread Tools

Search Thread

Display

Can you initialize arrays in the class declaration

Similar Threads

Problem with friend class declaration in a namespace

Forward Declaration of Class Members?

Screwy Linker Error - VC2005

C++ Class to add two boolean arrays or 1 boolean array with a int

Warnings, warnings, warnings?