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copy constructor issues HELP

mdeeza (11)
Hello. I'm currently wrapping up on a project which uses a doubly linked list toolkit to work with a sequence class. During which I can't get my copy constructor to function with my given driver (can't change driver)

I get this code
error C2274: 'function-style cast' : illegal as right side of '.' operator

Below i will include both my driver and my sequence implementation. However also in this program is my dnode.h and dnode.cpp(implement) files with the following functions to aid
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size_t list_length(const dnode* head_ptr);
	void display(const dnode* head_ptr);
    void list_head_insert(dnode*& head_ptr, const value_type& entry); 
    void list_insert(dnode* previous_ptr, const value_type& entry);  
    dnode* list_search(dnode* head_ptr, const value_type& target);
    const dnode* list_search (const dnode* head_ptr, const value_type& target);
    dnode* list_locate(dnode* head_ptr, size_t position);
    const dnode* list_locate(const dnode* head_ptr, size_t position);
    void list_head_remove(dnode*& head_ptr);
    void list_remove(dnode* remove_ptr);
    void list_clear(dnode*& head_ptr);
    void list_copy(const dnode* source_ptr, dnode*& head_ptr, dnode*& tail_ptr);

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#include <cassert>    // Provides assert
#include <cstdlib>    // Provides NULL and size_t
#include <iostream>
#include"sequence2.h"

//Constructor
sequence::sequence( )
{
	head_ptr = NULL;
	current_ptr = NULL;
}

//Copy Constructor
sequence::sequence(const sequence & source)
{		
        dnode * tail_ptr;
	list_copy(source.head_ptr, head_ptr, tail_ptr);
	if(source.current_ptr != NULL)
	   current_ptr = list_search(head_ptr, source.current_ptr->data());
	else
		current_ptr = NULL;
        
       
	

}

//Destructor
sequence::~sequence()
{
	list_clear(head_ptr);
	current_ptr = NULL;
}

//Has the current pointer equal the start
void sequence::start()
{
	current_ptr = head_ptr;
	
}

//Displays the list
void sequence::show_sequence()
{
	display(head_ptr);
}

}


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#include<iostream>
#include <cctype>       // Provides toupper
#include <cstdlib>      // Provides EXIT_SUCCESS
#include"sequence2.h"

using namespace std;

// PROTOTYPES for functions used by this test program:
void print_menu( );
// Postcondition: A menu of choices for this program has been written to cout.

char get_user_command( );
// Postcondition: The user has been prompted to enter a one character command.
// The next character has been read (skipping blanks and newline characters), 
// and this character has been returned.

double get_number( );
// Postcondition: The user has been prompted to enter a real number. The
// number has been read, echoed to the screen, and returned by the function.

sequence cctest(const sequence & source);

int main( )
{
    sequence test, test2; // A sequence that we'll perform tests on
    char choice;   // A command character entered by the user
    dnode * head = NULL;

    cout << "I have initialized an empty sequence of real numbers." << endl;

    do
    {
        print_menu( );
        choice = toupper(get_user_command( ));
        switch (choice)
        {
            case '!': test.start( );
                      break;
		    case '+': test.advance( );
                      break;
			case '-': test.moveback();
				      break;
			case '=': test2 = test;
				      test2.show_sequence();
				      break;
            case '?': if (test.is_item( ))
                          cout << "There is an item." << endl;
                     else 
                          cout << "There is no current item." << endl;
                      break;
            case 'C': if (test.is_item( ))
                           cout << "Current item is: " << test.current( ) << endl;
                     else
                          cout << "There is no current item." << endl;
                      break;
			case 'X': test.sequence( ); // ERROR ON THIS LINE
				cout << "Testing the copy function" << endl;
				     break;
            case 'P': test.show_sequence();
                      break;
            case 'S': cout << "Size is " << test.size( ) << '.' << endl;
                      break;
            case 'I': test.insert(get_number());
                      break;
            case 'A': test.attach(get_number());
                      break;
			case 'T': test.tail();
				      break;
			case 'R': test.remove_current( );
                      cout << "The current item has been removed." << endl;
                      break;
			case 'D': test.~sequence();
				      break;     
            case 'Q': cout << "Ridicule is the best test of truth." << endl;
                      break;
			
            default:  cout << choice << " is invalid." << endl;
        }
    }
    while ((choice != 'Q'));

    return EXIT_SUCCESS;
}

void print_menu( )
{
    cout << endl; // Print blank line before the menu
    cout << "The following choices are available: " << endl;
    cout << " !   Activate the start( ) function" << endl;
    cout << " +   Activate the advance( ) function" << endl;
	cout << " -   Activate the moveBack() function" << endl;
	cout << " =   Activate the operator= function" << endl;
    cout << " ?   Print the result from the is_item( ) function" << endl;
    cout << " C   Print the result from the current( ) function" << endl;
	cout << " X   Activate the Copy Constructor" << endl;
    cout << " P   Print the entire sequence" << endl;
    cout << " S   Print the result from the size( ) function" << endl;
    cout << " I   Insert a new number with the insert(...) function" << endl;
    cout << " A   Attach a new number with the attach(...) function" << endl;
	cout << " T   Activate the tail() function" << endl;
    cout << " R   Activate the remove_current( ) function" << endl;
	cout << " D   To destory the list(destructor)" << endl;
    cout << " Q   Quit this test program" << endl;
}

char get_user_command( )
{
    char command;

    cout << "Enter choice: ";
    cin >> command; // Input of characters skips blanks and newline character

    return command;
}


double get_number( )
{
    double result;
    
    cout << "Please enter a real number for the sequence: ";
    cin  >> result;
    cout << result << " has been read." << endl;
    return result;
}

sequence cctest(const sequence & source)
{
	sequence test(source);

	return test;
}
ne555 (10692)
> test.sequence( ); // ERROR ON THIS LINE
¿what do you think you are doing there?

> case 'D': test.~sequence();
bad idea
the destructor is invoked automagically when the variable goes out of scope, so you'll end calling it twice
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