Memberwise copy

Pages: 12
hooshdar3 (257)
Hello.What's wrong with the following code snippet?
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  for( list<Conference>::iterator it = conferences.begin();it != conferences.end();++it )
           if( strcmp(it->getTitle(),t) == 0 )
	          cf = *it;


thank you in advance
helios (17607)
What are you looking for?
hooshdar3 (257)
A specific Conference in the list of conferences whoe title matches a certain value.then copying it in an object of type Conference(cf).

This is the function in which the error occures:
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void User::modifyConference(){
	
  Arbiter   objArbiter;
   Article   objArticle;

   char t[100];
   
   Conference cf;
 
   if( strcmp(session->getUserType(), "manager") )
   {
   	   cout << "enter Conference\'s title you want to modify:[80 characters]" <<endl;
	   cin.getline( t, 80 );
        
 	   for( list<Conference>::iterator it = conferences.begin();it != conferences.end();++it )
           if( strcmp(it->getTitle(),t) == 0 )
	          cf = *it;	//This line errs!!!!!
            
           cf.update();
   }//end if
   
}
Last edited on
helios (17607)
No, I mean, what's not working for you? It's hard if not impossible to tell what could be going wrong here without some more information.
hooshdar3 (257)
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for( list<Conference>::iterator it = conferences.begin();it != conferences.end();++it )
           if( strcmp(it->getTitle(),t) == 0 )
	          cf = *it;	//This line errs!!!!!
helios (17607)
Okay, what's the error?
hooshdar3 (257)
The error is:

91 Z:\media\g_\fff\implementation.cpp instantiated from here


very descriptive an error indeed!

I am using dev-cpp
Last edited on
helios (17607)
Post all the error messages.
closed account (EzwRko23)
Welcome to the Template Paradise of Informative Error Messages! :D
Sorry, guys, I couldn't resist.

Change your IDE. Dev-Cpp is ancient and broken, and does not print all the messages.
Use Eclipse CDT or IntelliJ IDEA with a proper plugin. Works great for me.
You can also use Code::Blocks but it is not as feature rich.
Last edited on
hooshdar3 (257)
Post all the error messages.


ok.
91 Z:\media\g_\fff\implementation.cpp instantiated from here

129 Z:\media\g_\Dev-Cpp\include\c++\3.4.2\bits\list.tcc ISO C++ forbids assignment of arrays 
 
 
436 Z:\media\g_\Dev-Cpp\include\c++\3.4.2\bits\stl_list.h   instantiated from `std::_List_node<_Tp>* std::list<_Tp, _Alloc>::_M_create_node(const _Tp&) [with _Tp = char[101], _Alloc = std::allocator<char[101]>]'  

 
 
1161 Z:\media\g_\Dev-Cpp\include\c++\3.4.2\bits\stl_list.h   instantiated from `void std::list<_Tp, _Alloc>::_M_insert(std::_List_iterator<_Tp>, const _Tp&) [with _Tp = char[101], _Alloc = std::allocator<char[101]>]'  

 
 
783 Z:\media\g_\Dev-Cpp\include\c++\3.4.2\bits\stl_list.h   instantiated from `void std::list<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = char[101], _Alloc = std::allocator<char[101]>]'


764 Z:\media\g_\fff\implementation.cpp instantiated from here

81 Z:\media\g_\Dev-Cpp\include\c++\3.4.2\bits\stl_construct.h ISO C++ forbids initialization in array new
helios (17607)
The error is saying that you can't copy arrays this way:
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char a[10],b[10];
b=a;
I assume Conference::operator=() does something like that in its body to copy the title member. I recommend using an std::string instead.
Alternatively, you could use strncpy().
hooshdar3 (257)
strncpy, where?
helios (17607)
In the operator=() overload, but I strongly recommend using an std::string.
hooshdar3 (257)
I should first study how to overload a function again!!

thhen, I will have difficulty Serializing a String.
helios (17607)
Maybe I assumed something wrong about your code. Why don't you post the complete implementation of Conference?
Last edited on
hooshdar3 (257)
this is Conference's defiinintion:
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class  Conference   //implemented
{
   public: 
	Conference(User *);
  	void 		setTitle( char* t ){strcpy(title, t);} 		      		//implemented
	char* 		getTitle(){return title;}                	      		//implemented
  	void 		callForPapers();              		      				//implemented
  	char* 		getConferenceHall(){return hall;}	      				//implemented
 	void 		setConferenceHall( char* avenue){strcpy(hall, avenue);} //implemented
  	void 		createWebsiite(){website = new Website( this);}  		//implemented
  	void  	    addTheme();			                          		    //implemented         
	void 	    showInfo();		 	      					  		    //implemented
    void 	    update();				      				  		    //implemented
    void    	setFee();				                      		    //implemented
    int 	    getFee(){return fee;}                         		    //implemented
	void        setManagerID(char id[11]){strcpy(managerID,id);}        //implemented
	char*       getManagerID(){return managerID;}
	void 		showThemes();
  	Time 	     submissionDeadline;
  	list<char[101]> themes;
  	char         anouncement[100];
  	Website*     website;
	User		 manager;	
        
   private:
   	       char      title[100];
   	       char      hall[100];
		   char		 managerID[11];
           int 		 fee;


and here, the implementation:

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Conference::Conference(User *oManager)

{

   cout << "******************conference c-tor******************************" << endl;

	manager = *oManager;

}

/************************************************************/

void Conference::setFee()

{

  int f;



  cout << "enter the fee" << endl;

  cin >> f;



fee = f>0?f:0;

}

/***************************************************************/

void Conference::update()

{

  char h[100]="";



  cout << "\thall is:\t"<< hall << "\nenter new hall(Enter for no change)" << endl;

  cin >> h;



  if( !strcmp(h, "") )

    strcpy(hall, h );



     strcpy(h, "");  



   cout << "\tTitle is:\t"<< title << "\nenter new Title(Enter for no change)" << endl;

   cin >> h;



     strcpy(h, "");  



  if( !strcmp(h, "") )

    strcpy(title,  h );  



   strcpy(h,"");



   cout << "\tanouncement is:\t"<< anouncement << "\nenter new Title(Enter for no change)" << endl;

  cin >> h;



  if( !strcmp(h, "") )

  {

     strcpy(anouncement, h );

     callForPapers();

  }



  cout << "\tparticipation fee is:\t"<< fee << "\nenter new paticipation fee(Enter for no change)" << endl;

  cin >> fee;



}//end Conference::update()

/*******************************************************/

void   Conference::showInfo()

{

  cout << "\thall:\t"<< hall << "\n\ttitle:\t" << title << endl;

  cout << "themes:" << endl;

  cout << "       ";



  for( list<char[101]>::iterator it = themes.begin();it != themes.end();++it )



     cout << "\t" << *it;

   

}

/****************************************************/

void Conference::callForPapers()

{

   cout << anouncement;

} 

/*************************************************/

void Conference::addTheme()

{

   char theme[101];



   cout << "Enter the theme" << endl;

   cin.getline( theme, 100 );

   

   themes.push_back( theme );

}

/***********************************************/

void Conference::showThemes()

{

	list<char[101]>::iterator it = themes.begin();

	for( ;it!= themes.end();++it )

	{

		cout << *it << endl;

	}

	  

}

hooshdar3 (257)
hello?!
helios (17607)
I got nothing.
hooshdar3 (257)
ok I changed the
list<char[101]> themes

to
 
 
char themes [100][100]


and I changed the related code accoedingly

the error disappeared
but now I get linker error.could u plz help me with the link error?
Last edited on
hooshdar3 (257)
hello?!
Pages: 12