Can`t overload the operator << for a my own class

-2

I am trying to reduce code redundancy using the overload of an output operator to a stream instead of print functions.

//***.h

class MainWind : public QWidget

{

    Q_OBJECT



public:

    explicit MainWind(QWidget *parent = nullptr);

    ~MainWind();

    MainWind *operator<<(const QString &str);

private:

    Ui::MainWind *ui;

};



//***.cpp

MainWind *MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return this;

}

At this moment everything compiles successfully.

But when I try to use:

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind << QString("str");

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'QString')
qstring.h:1410: candidate function not viable: no known conversion from >'MainWind *' to 'QDataStream &' for 1st argument

...

And there are a lot of candidates for this position)

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'const char [4]') ServerSocket.cpp:39: error:
invalid operands of types 'MainWind*' and 'const char [4]' to binary
'operator<<'
CurrentSession::inst().mainWind() << "str";
                                                  ^

What could be the problem?

ADDITION TO THIS QUESTION:

Attempt to use:

//*.h

friend MainWind *operator<<(MainWind *out,QString &str);



//***.cpp

MainWind * operator<<(MainWind *out, QString &str)

{

    out->ui->serverConsole->insertPlainText(str);

    return out;

}

Compilation of previous code is successful.

According to the idea, if the first operand could not be a pointer, this code would not compile...

But when using this:

//other.cpp

MainWind *mW = new MainWind;

mW << "str";

Compilation go to error:

ServerSocket.cpp:37: error: invalid operands of types 'MainWind*' and 'const char [4]' to binary 'operator<<'
mW << "str";
                ^

edited Jan 2 at 2:46

asked Jan 2 at 1:05

Vlad

The problem is that you defined the << overload an a MainWind, and the left-hand operand of this << operator is not a MainWind. It is a MainWind *.

– Sam Varshavchik
Jan 2 at 1:08

add a comment |

-2

I am trying to reduce code redundancy using the overload of an output operator to a stream instead of print functions.

//***.h

class MainWind : public QWidget

{

    Q_OBJECT



public:

    explicit MainWind(QWidget *parent = nullptr);

    ~MainWind();

    MainWind *operator<<(const QString &str);

private:

    Ui::MainWind *ui;

};



//***.cpp

MainWind *MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return this;

}

At this moment everything compiles successfully.

But when I try to use:

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind << QString("str");

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'QString')
qstring.h:1410: candidate function not viable: no known conversion from >'MainWind *' to 'QDataStream &' for 1st argument

...

And there are a lot of candidates for this position)

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'const char [4]') ServerSocket.cpp:39: error:
invalid operands of types 'MainWind*' and 'const char [4]' to binary
'operator<<'
CurrentSession::inst().mainWind() << "str";
                                                  ^

What could be the problem?

ADDITION TO THIS QUESTION:

Attempt to use:

//*.h

friend MainWind *operator<<(MainWind *out,QString &str);



//***.cpp

MainWind * operator<<(MainWind *out, QString &str)

{

    out->ui->serverConsole->insertPlainText(str);

    return out;

}

Compilation of previous code is successful.

According to the idea, if the first operand could not be a pointer, this code would not compile...

But when using this:

//other.cpp

MainWind *mW = new MainWind;

mW << "str";

Compilation go to error:

ServerSocket.cpp:37: error: invalid operands of types 'MainWind*' and 'const char [4]' to binary 'operator<<'
mW << "str";
                ^

edited Jan 2 at 2:46

asked Jan 2 at 1:05

Vlad

The problem is that you defined the << overload an a MainWind, and the left-hand operand of this << operator is not a MainWind. It is a MainWind *.

– Sam Varshavchik
Jan 2 at 1:08

add a comment |

-2

I am trying to reduce code redundancy using the overload of an output operator to a stream instead of print functions.

//***.h

class MainWind : public QWidget

{

    Q_OBJECT



public:

    explicit MainWind(QWidget *parent = nullptr);

    ~MainWind();

    MainWind *operator<<(const QString &str);

private:

    Ui::MainWind *ui;

};



//***.cpp

MainWind *MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return this;

}

At this moment everything compiles successfully.

But when I try to use:

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind << QString("str");

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'QString')
qstring.h:1410: candidate function not viable: no known conversion from >'MainWind *' to 'QDataStream &' for 1st argument

...

And there are a lot of candidates for this position)

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'const char [4]') ServerSocket.cpp:39: error:
invalid operands of types 'MainWind*' and 'const char [4]' to binary
'operator<<'
CurrentSession::inst().mainWind() << "str";
                                                  ^

What could be the problem?

ADDITION TO THIS QUESTION:

Attempt to use:

//*.h

friend MainWind *operator<<(MainWind *out,QString &str);



//***.cpp

MainWind * operator<<(MainWind *out, QString &str)

{

    out->ui->serverConsole->insertPlainText(str);

    return out;

}

Compilation of previous code is successful.

According to the idea, if the first operand could not be a pointer, this code would not compile...

But when using this:

//other.cpp

MainWind *mW = new MainWind;

mW << "str";

Compilation go to error:

ServerSocket.cpp:37: error: invalid operands of types 'MainWind*' and 'const char [4]' to binary 'operator<<'
mW << "str";
                ^

edited Jan 2 at 2:46

asked Jan 2 at 1:05

Vlad

I am trying to reduce code redundancy using the overload of an output operator to a stream instead of print functions.

//***.h

class MainWind : public QWidget

{

    Q_OBJECT



public:

    explicit MainWind(QWidget *parent = nullptr);

    ~MainWind();

    MainWind *operator<<(const QString &str);

private:

    Ui::MainWind *ui;

};



//***.cpp

MainWind *MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return this;

}

At this moment everything compiles successfully.

But when I try to use:

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind << QString("str");

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'QString')
qstring.h:1410: candidate function not viable: no known conversion from >'MainWind *' to 'QDataStream &' for 1st argument

...

And there are a lot of candidates for this position)

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

I got this error:

ServerSocket.cpp:39: error: invalid operands to binary expression
('MainWind *' and 'const char [4]') ServerSocket.cpp:39: error:
invalid operands of types 'MainWind*' and 'const char [4]' to binary
'operator<<'
CurrentSession::inst().mainWind() << "str";
                                                  ^

What could be the problem?

ADDITION TO THIS QUESTION:

Attempt to use:

//*.h

friend MainWind *operator<<(MainWind *out,QString &str);



//***.cpp

MainWind * operator<<(MainWind *out, QString &str)

{

    out->ui->serverConsole->insertPlainText(str);

    return out;

}

Compilation of previous code is successful.

According to the idea, if the first operand could not be a pointer, this code would not compile...

But when using this:

//other.cpp

MainWind *mW = new MainWind;

mW << "str";

Compilation go to error:

ServerSocket.cpp:37: error: invalid operands of types 'MainWind*' and 'const char [4]' to binary 'operator<<'
mW << "str";
                ^

c++ qt

edited Jan 2 at 2:46

asked Jan 2 at 1:05

Vlad

edited Jan 2 at 2:46

asked Jan 2 at 1:05

Vlad

edited Jan 2 at 2:46

asked Jan 2 at 1:05

Vlad

asked Jan 2 at 1:05

Vlad

asked Jan 2 at 1:05

Vlad

The problem is that you defined the << overload an a MainWind, and the left-hand operand of this << operator is not a MainWind. It is a MainWind *.

– Sam Varshavchik
Jan 2 at 1:08

add a comment |

The problem is that you defined the << overload an a MainWind, and the left-hand operand of this << operator is not a MainWind. It is a MainWind *.

– Sam Varshavchik
Jan 2 at 1:08

The problem is that you defined the << overload an a MainWind, and the left-hand operand of this << operator is not a MainWind. It is a MainWind *.

– Sam Varshavchik
Jan 2 at 1:08

add a comment |

3 Answers
3

active

oldest

votes

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

The reason is that mainWind << "str" looks for an operator<<() that accepts two arguments, the first of which is a MainWind *.

Whereas, you have defined a MainWind::operator<<() which is called with the first argument a MainWind &. There is no direct conversion from a MainWind * to a MainWind & (or to a MainWind). Hence the error message.

One way to get the code to compile is to change mainWind <<"str" to *mainWind << "str". The * dereferences the pointer, and produces a reference, which is what your operator<<() expects.

The catch is then that

*mainWind << "str" << "another str";

will not compile, since it is equivalent to

(*mainWind).operator<<("str") << "another str";

where (*mainWind).operator<<("str") returns a MainWind *. This causes the same problem (again) when trying to stream "another str".

The real fix is to change operator<<() so it returns a reference

//  within the class definition of MainWind



MainWind &operator<<(const QString &str);



// definition of the operator<<()



MainWind &MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

and change the calling code to either

//other.cpp version 2



MainWind *mainWind  = new MainWind;

*mainWind <<"str";



// this will work too



*mainWind << "str" << "another str";  



//   note reliance on cleaning up mainWind to avoid a memory leak



delete mainWind;

There is no other fix that would allow you to use mainWind << "str" since overloading non-member operator<<() is only permitted on class or enumerated types, not on pointers.

edited Jan 2 at 2:12

answered Jan 2 at 1:52

Peter

27.9k32157

A lot of text makes little sense ... How do I overload the function as in addition to my question?

– Vlad
Jan 2 at 1:59

@Vlad - I've edited to address that.

– Peter
Jan 2 at 2:00

I would like to using the pointer without the "*". Therefore, I want to overload the function.

– Vlad
Jan 2 at 2:00

@Vlad - my edit addresses that too.

– Peter
Jan 2 at 2:03

Your example of function overload still result error: MainWind *mW = new MainWind; mW << "str"; This is for your last insight? Maybe I do not use it correctly?

– Vlad
Jan 2 at 2:09

|
show 3 more comments

You need to use *mainWind << QString("str");. The LHS has to be an object, not a pointer.

While at it, I strongly recommend changing the operator<< function to return a reference to the object, not a pointer.

MainWind& operator<<(const QString &str);

and the implementation to

MainWind& MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

That will allow you to chain the operator.

*mainWind << QString("str") << QString("Second string");

edited Jan 2 at 1:46

answered Jan 2 at 1:10

R Sahu

168k1292191

This is fine, but I need to work with exactly the pointer, but the function overloading given above gives to me a result similar to the past.

– Vlad
Jan 2 at 1:51

@Vlad, using pointers instead of objects is a choice. I am sure it is not a requirement. Morever, using pointers with the << operators is not idiomatic. Just something to think about.

– R Sahu
Jan 2 at 3:30

add a comment |

You overloaded << on MainWnd not MainWnd*.

*mainWind << QString("str");

Also you want QString const&

edited Jan 2 at 3:08

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

And if I want to use the pointer yet? without the "*" at the beginning. Is it possible? How should I change the overload?

– Vlad
Jan 2 at 1:13

@Vlad, you can use mainWind->operator<<(QString("str"));

– R Sahu
Jan 2 at 1:17

@RSahu , This is code redundancy. Nobody does it

– Vlad
Jan 2 at 1:30

@Vlad, that's why you should use *mainWind << ...

– R Sahu
Jan 2 at 1:32

1

@Vlad, try making the second argument QString const& str.

– R Sahu
Jan 2 at 1:43

|
show 2 more comments

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3 Answers
3

active

oldest

votes

3 Answers
3

active

oldest

votes

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

The reason is that mainWind << "str" looks for an operator<<() that accepts two arguments, the first of which is a MainWind *.

One way to get the code to compile is to change mainWind <<"str" to *mainWind << "str". The * dereferences the pointer, and produces a reference, which is what your operator<<() expects.

The catch is then that

*mainWind << "str" << "another str";

will not compile, since it is equivalent to

(*mainWind).operator<<("str") << "another str";

where (*mainWind).operator<<("str") returns a MainWind *. This causes the same problem (again) when trying to stream "another str".

The real fix is to change operator<<() so it returns a reference

//  within the class definition of MainWind



MainWind &operator<<(const QString &str);



// definition of the operator<<()



MainWind &MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

and change the calling code to either

//other.cpp version 2



MainWind *mainWind  = new MainWind;

*mainWind <<"str";



// this will work too



*mainWind << "str" << "another str";  



//   note reliance on cleaning up mainWind to avoid a memory leak



delete mainWind;

There is no other fix that would allow you to use mainWind << "str" since overloading non-member operator<<() is only permitted on class or enumerated types, not on pointers.

edited Jan 2 at 2:12

answered Jan 2 at 1:52

Peter

27.9k32157

A lot of text makes little sense ... How do I overload the function as in addition to my question?

– Vlad
Jan 2 at 1:59

@Vlad - I've edited to address that.

– Peter
Jan 2 at 2:00

I would like to using the pointer without the "*". Therefore, I want to overload the function.

– Vlad
Jan 2 at 2:00

@Vlad - my edit addresses that too.

– Peter
Jan 2 at 2:03

Your example of function overload still result error: MainWind *mW = new MainWind; mW << "str"; This is for your last insight? Maybe I do not use it correctly?

– Vlad
Jan 2 at 2:09

|
show 3 more comments

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

The reason is that mainWind << "str" looks for an operator<<() that accepts two arguments, the first of which is a MainWind *.

One way to get the code to compile is to change mainWind <<"str" to *mainWind << "str". The * dereferences the pointer, and produces a reference, which is what your operator<<() expects.

The catch is then that

*mainWind << "str" << "another str";

will not compile, since it is equivalent to

(*mainWind).operator<<("str") << "another str";

where (*mainWind).operator<<("str") returns a MainWind *. This causes the same problem (again) when trying to stream "another str".

The real fix is to change operator<<() so it returns a reference

//  within the class definition of MainWind



MainWind &operator<<(const QString &str);



// definition of the operator<<()



MainWind &MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

and change the calling code to either

//other.cpp version 2



MainWind *mainWind  = new MainWind;

*mainWind <<"str";



// this will work too



*mainWind << "str" << "another str";  



//   note reliance on cleaning up mainWind to avoid a memory leak



delete mainWind;

There is no other fix that would allow you to use mainWind << "str" since overloading non-member operator<<() is only permitted on class or enumerated types, not on pointers.

edited Jan 2 at 2:12

answered Jan 2 at 1:52

Peter

27.9k32157

A lot of text makes little sense ... How do I overload the function as in addition to my question?

– Vlad
Jan 2 at 1:59

@Vlad - I've edited to address that.

– Peter
Jan 2 at 2:00

I would like to using the pointer without the "*". Therefore, I want to overload the function.

– Vlad
Jan 2 at 2:00

@Vlad - my edit addresses that too.

– Peter
Jan 2 at 2:03

Your example of function overload still result error: MainWind *mW = new MainWind; mW << "str"; This is for your last insight? Maybe I do not use it correctly?

– Vlad
Jan 2 at 2:09

|
show 3 more comments

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

The reason is that mainWind << "str" looks for an operator<<() that accepts two arguments, the first of which is a MainWind *.

One way to get the code to compile is to change mainWind <<"str" to *mainWind << "str". The * dereferences the pointer, and produces a reference, which is what your operator<<() expects.

The catch is then that

*mainWind << "str" << "another str";

will not compile, since it is equivalent to

(*mainWind).operator<<("str") << "another str";

where (*mainWind).operator<<("str") returns a MainWind *. This causes the same problem (again) when trying to stream "another str".

The real fix is to change operator<<() so it returns a reference

//  within the class definition of MainWind



MainWind &operator<<(const QString &str);



// definition of the operator<<()



MainWind &MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

and change the calling code to either

//other.cpp version 2



MainWind *mainWind  = new MainWind;

*mainWind <<"str";



// this will work too



*mainWind << "str" << "another str";  



//   note reliance on cleaning up mainWind to avoid a memory leak



delete mainWind;

There is no other fix that would allow you to use mainWind << "str" since overloading non-member operator<<() is only permitted on class or enumerated types, not on pointers.

edited Jan 2 at 2:12

answered Jan 2 at 1:52

Peter

27.9k32157

//other.cpp

MainWind *mainWind  = new MainWind;

mainWind <<"str";

The reason is that mainWind << "str" looks for an operator<<() that accepts two arguments, the first of which is a MainWind *.

One way to get the code to compile is to change mainWind <<"str" to *mainWind << "str". The * dereferences the pointer, and produces a reference, which is what your operator<<() expects.

The catch is then that

*mainWind << "str" << "another str";

will not compile, since it is equivalent to

(*mainWind).operator<<("str") << "another str";

where (*mainWind).operator<<("str") returns a MainWind *. This causes the same problem (again) when trying to stream "another str".

The real fix is to change operator<<() so it returns a reference

//  within the class definition of MainWind



MainWind &operator<<(const QString &str);



// definition of the operator<<()



MainWind &MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

and change the calling code to either

//other.cpp version 2



MainWind *mainWind  = new MainWind;

*mainWind <<"str";



// this will work too



*mainWind << "str" << "another str";  



//   note reliance on cleaning up mainWind to avoid a memory leak



delete mainWind;

There is no other fix that would allow you to use mainWind << "str" since overloading non-member operator<<() is only permitted on class or enumerated types, not on pointers.

edited Jan 2 at 2:12

answered Jan 2 at 1:52

Peter

27.9k32157

edited Jan 2 at 2:12

answered Jan 2 at 1:52

Peter

27.9k32157

answered Jan 2 at 1:52

Peter

27.9k32157

answered Jan 2 at 1:52

Peter

27.9k32157

A lot of text makes little sense ... How do I overload the function as in addition to my question?

– Vlad
Jan 2 at 1:59

@Vlad - I've edited to address that.

– Peter
Jan 2 at 2:00

I would like to using the pointer without the "*". Therefore, I want to overload the function.

– Vlad
Jan 2 at 2:00

@Vlad - my edit addresses that too.

– Peter
Jan 2 at 2:03

Your example of function overload still result error: MainWind *mW = new MainWind; mW << "str"; This is for your last insight? Maybe I do not use it correctly?

– Vlad
Jan 2 at 2:09

|
show 3 more comments

A lot of text makes little sense ... How do I overload the function as in addition to my question?

– Vlad
Jan 2 at 1:59

@Vlad - I've edited to address that.

– Peter
Jan 2 at 2:00

I would like to using the pointer without the "*". Therefore, I want to overload the function.

– Vlad
Jan 2 at 2:00

@Vlad - my edit addresses that too.

– Peter
Jan 2 at 2:03

Your example of function overload still result error: MainWind *mW = new MainWind; mW << "str"; This is for your last insight? Maybe I do not use it correctly?

– Vlad
Jan 2 at 2:09

A lot of text makes little sense ... How do I overload the function as in addition to my question?

– Vlad
Jan 2 at 1:59

@Vlad - I've edited to address that.

– Peter
Jan 2 at 2:00

I would like to using the pointer without the "*". Therefore, I want to overload the function.

– Vlad
Jan 2 at 2:00

@Vlad - my edit addresses that too.

– Peter
Jan 2 at 2:03

Your example of function overload still result error: MainWind *mW = new MainWind; mW << "str"; This is for your last insight? Maybe I do not use it correctly?

– Vlad
Jan 2 at 2:09

|
show 3 more comments

You need to use *mainWind << QString("str");. The LHS has to be an object, not a pointer.

While at it, I strongly recommend changing the operator<< function to return a reference to the object, not a pointer.

MainWind& operator<<(const QString &str);

and the implementation to

MainWind& MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

That will allow you to chain the operator.

*mainWind << QString("str") << QString("Second string");

edited Jan 2 at 1:46

answered Jan 2 at 1:10

R Sahu

168k1292191

This is fine, but I need to work with exactly the pointer, but the function overloading given above gives to me a result similar to the past.

– Vlad
Jan 2 at 1:51

@Vlad, using pointers instead of objects is a choice. I am sure it is not a requirement. Morever, using pointers with the << operators is not idiomatic. Just something to think about.

– R Sahu
Jan 2 at 3:30

add a comment |

You need to use *mainWind << QString("str");. The LHS has to be an object, not a pointer.

While at it, I strongly recommend changing the operator<< function to return a reference to the object, not a pointer.

MainWind& operator<<(const QString &str);

and the implementation to

MainWind& MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

That will allow you to chain the operator.

*mainWind << QString("str") << QString("Second string");

edited Jan 2 at 1:46

answered Jan 2 at 1:10

R Sahu

168k1292191

This is fine, but I need to work with exactly the pointer, but the function overloading given above gives to me a result similar to the past.

– Vlad
Jan 2 at 1:51

@Vlad, using pointers instead of objects is a choice. I am sure it is not a requirement. Morever, using pointers with the << operators is not idiomatic. Just something to think about.

– R Sahu
Jan 2 at 3:30

add a comment |

You need to use *mainWind << QString("str");. The LHS has to be an object, not a pointer.

While at it, I strongly recommend changing the operator<< function to return a reference to the object, not a pointer.

MainWind& operator<<(const QString &str);

and the implementation to

MainWind& MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

That will allow you to chain the operator.

*mainWind << QString("str") << QString("Second string");

edited Jan 2 at 1:46

answered Jan 2 at 1:10

R Sahu

168k1292191

You need to use *mainWind << QString("str");. The LHS has to be an object, not a pointer.

While at it, I strongly recommend changing the operator<< function to return a reference to the object, not a pointer.

MainWind& operator<<(const QString &str);

and the implementation to

MainWind& MainWind::operator<<(const QString &str)

{

    ui->serverConsole->insertPlainText(str);

    return *this;

}

That will allow you to chain the operator.

*mainWind << QString("str") << QString("Second string");

edited Jan 2 at 1:46

answered Jan 2 at 1:10

R Sahu

168k1292191

edited Jan 2 at 1:46

answered Jan 2 at 1:10

R Sahu

168k1292191

answered Jan 2 at 1:10

R Sahu

168k1292191

answered Jan 2 at 1:10

R Sahu

168k1292191

This is fine, but I need to work with exactly the pointer, but the function overloading given above gives to me a result similar to the past.

– Vlad
Jan 2 at 1:51

@Vlad, using pointers instead of objects is a choice. I am sure it is not a requirement. Morever, using pointers with the << operators is not idiomatic. Just something to think about.

– R Sahu
Jan 2 at 3:30

add a comment |

This is fine, but I need to work with exactly the pointer, but the function overloading given above gives to me a result similar to the past.

– Vlad
Jan 2 at 1:51

@Vlad, using pointers instead of objects is a choice. I am sure it is not a requirement. Morever, using pointers with the << operators is not idiomatic. Just something to think about.

– R Sahu
Jan 2 at 3:30

This is fine, but I need to work with exactly the pointer, but the function overloading given above gives to me a result similar to the past.

– Vlad
Jan 2 at 1:51

@Vlad, using pointers instead of objects is a choice. I am sure it is not a requirement. Morever, using pointers with the << operators is not idiomatic. Just something to think about.

– R Sahu
Jan 2 at 3:30

add a comment |

You overloaded << on MainWnd not MainWnd*.

*mainWind << QString("str");

Also you want QString const&

edited Jan 2 at 3:08

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

And if I want to use the pointer yet? without the "*" at the beginning. Is it possible? How should I change the overload?

– Vlad
Jan 2 at 1:13

@Vlad, you can use mainWind->operator<<(QString("str"));

– R Sahu
Jan 2 at 1:17

@RSahu , This is code redundancy. Nobody does it

– Vlad
Jan 2 at 1:30

@Vlad, that's why you should use *mainWind << ...

– R Sahu
Jan 2 at 1:32

1

@Vlad, try making the second argument QString const& str.

– R Sahu
Jan 2 at 1:43

|
show 2 more comments

You overloaded << on MainWnd not MainWnd*.

*mainWind << QString("str");

Also you want QString const&

edited Jan 2 at 3:08

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

And if I want to use the pointer yet? without the "*" at the beginning. Is it possible? How should I change the overload?

– Vlad
Jan 2 at 1:13

@Vlad, you can use mainWind->operator<<(QString("str"));

– R Sahu
Jan 2 at 1:17

@RSahu , This is code redundancy. Nobody does it

– Vlad
Jan 2 at 1:30

@Vlad, that's why you should use *mainWind << ...

– R Sahu
Jan 2 at 1:32

1

@Vlad, try making the second argument QString const& str.

– R Sahu
Jan 2 at 1:43

|
show 2 more comments

You overloaded << on MainWnd not MainWnd*.

*mainWind << QString("str");

Also you want QString const&

edited Jan 2 at 3:08

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

You overloaded << on MainWnd not MainWnd*.

*mainWind << QString("str");

Also you want QString const&

edited Jan 2 at 3:08

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

edited Jan 2 at 3:08

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

answered Jan 2 at 1:08

Yakk - Adam Nevraumont

187k21199384

And if I want to use the pointer yet? without the "*" at the beginning. Is it possible? How should I change the overload?

– Vlad
Jan 2 at 1:13

@Vlad, you can use mainWind->operator<<(QString("str"));

– R Sahu
Jan 2 at 1:17

@RSahu , This is code redundancy. Nobody does it

– Vlad
Jan 2 at 1:30

@Vlad, that's why you should use *mainWind << ...

– R Sahu
Jan 2 at 1:32

1

@Vlad, try making the second argument QString const& str.

– R Sahu
Jan 2 at 1:43

|
show 2 more comments

And if I want to use the pointer yet? without the "*" at the beginning. Is it possible? How should I change the overload?

– Vlad
Jan 2 at 1:13

@Vlad, you can use mainWind->operator<<(QString("str"));

– R Sahu
Jan 2 at 1:17

@RSahu , This is code redundancy. Nobody does it

– Vlad
Jan 2 at 1:30

@Vlad, that's why you should use *mainWind << ...

– R Sahu
Jan 2 at 1:32

1

@Vlad, try making the second argument QString const& str.

– R Sahu
Jan 2 at 1:43

And if I want to use the pointer yet? without the "*" at the beginning. Is it possible? How should I change the overload?

– Vlad
Jan 2 at 1:13

@Vlad, you can use mainWind->operator<<(QString("str"));

– R Sahu
Jan 2 at 1:17

@RSahu , This is code redundancy. Nobody does it

– Vlad
Jan 2 at 1:30

@Vlad, that's why you should use *mainWind << ...

– R Sahu
Jan 2 at 1:32

@Vlad, try making the second argument QString const& str.

– R Sahu
Jan 2 at 1:43

|
show 2 more comments

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