Error Checking

[jodytj]

// My error checking is not working and I have been unable to figure out why?
//driver.cpp 

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

using namespace std;

int main(int argc, char const *argv[])
{
	List Test;
	Test.insert("AAA", 0);
	Test.insert("BBB", 1);
	Test.insert("CCC", 2);
	Test.display(cout);
	cout << Test.getSize() << endl;


	List Test_Second;
	
	Test_Second = Test;

	Test_Second.display(cout);
	cout << Test_Second.getSize() << endl;

	Test_Second.insert("DDD", 3);

	List Test_Third(Test_Second);

	Test_Third.display(cout);
	cout << Test_Third.getSize() << endl;

    system ("pause");
	return 0;
}
//------------------------------------------------------------------------
//List.cpp

#include "List.h"

//Construct empty List
List::List()
{
	first = NULL;

	mySize = 0;
}

//Construct copy of source List
List::List( const List &source )
{
	first = NULL;

	mySize = -1;

	int index = 0;

	NodePointer current = source.first;

	while(current != NULL)
	{
		insert(current->data, index++);
		current = current->next;
	}
}

List::~List( )
{
	for(int i = 0; i <= mySize; i++)
		erase(i);
}

const List & List::operator=( const List &rightSide )
{
	int index = 0;

	NodePointer current = rightSide.first;

	while(current != NULL)
	{
		insert(current->data, index++);
		current = current->next;
	}

	return *this;
}

int List::getSize( ) const
{
	return mySize;
}

bool List::empty( ) const
{
	if(mySize == -1)
		return true;

	return false;
}

void List::insert( ElementType dataVal, int index )
{

	if(index == 0)
	{
		NodePointer NewNode =  new Node;

		NewNode->data = dataVal;
		NewNode->next = first;

		first = NewNode;

		mySize++;
	}
	else if(index > 0 && index <= (mySize + 1)) 
	{
		NodePointer current = first;

		for(int i = 0; i < index - 1; i++)
			current = current->next;

		NodePointer NewNode = new Node;

		NewNode->data = dataVal;
		NewNode->next = current->next;

		current->next = NewNode;

		mySize++;
	}

}

void List::erase( int index )
{
	if(first != NULL)
	{
		if(index == 0)
		{
			NodePointer temp = first;

			first = temp->next;

			delete temp;

			mySize--;
		}
		else if(index > 0 && index <= (mySize + 1))
		{
			NodePointer current = first;

			for(int i = 0; i < index -1; i++)
				current = current->next;

			NodePointer temp = current->next;

			current->next = temp->next;

			delete temp;

			mySize--;
		}
	}
}

void List::display( ostream &out ) const
{
	NodePointer current = first;

	while(current != NULL)
	{
		out << current->data << endl;
		current = current->next;
	}
}

int List::find( ElementType value) const
{
	NodePointer current = first;
	int index = 0;

	while(current != NULL)
	{
		if(current->data == value)
			return index;
		else
		{
			current = current->next;
			index++;
		}
	}

	return -1;
}
//----------------------------------------------------------------------------
// List.h

#ifndef LIST
	#define LIST

#include <iostream>
#include <cstdlib>
#include <string>

using namespace std;

typedef string ElementType;

class List
{
	private:

		class Node
		{
			public:

				ElementType data;

				Node * next;

				Node( ): data( ElementType( ) ), next( NULL )
				{ }

				Node( ElementType initData ): data( initData ), next( NULL )
				{ }
		}; // end of Node class

	typedef Node * NodePointer;

	public:

		List( );
		/* Construct a List object

		Precondition: none.
		Postcondition: An empty List object has been constructed.
		*/

		List( const List &source );
		/* Construct a copy of a List object.

		Precondition: None.
		Postcondition: A copy of source has been constructed.
		*/

		~List( );
		/* Destroys a List object.

		Precondition: None.
		Postcondition: Any memory allocated to the List object has been freed.
		*/

		const List & operator=( const List &rightSide );
		/* Assign a copy of a List object to the current object.

		Precondition: none
		Postcondition: A copy of rightside has been assigned to this
		object. A constant reference to this list is returned.
		*/

		int getSize( ) const;
		/* Returns the size of the list (number of items in the list)

		Precondition: none
		Postcondition: The return value is the number of items in the list.
		*/

		bool empty( ) const;
		/* Check if this List is empty

		Precondition: none
		Postcondition: The return value is true if this List object is empty;
		otherwise the return value is false.
		*/

		void insert( ElementType dataVal, int index );
		/* Insert a value into this List at a given index

		Precondition: The index is valid (0 <= index <= the list size).
		The first position is index 0, the second position is index 1, etc.
		Postcondition: dataval has been inserted into the list at the position
		determined by index (provided there is room and index is a legal
		position).
		*/

		void erase( int index );
		/* Remove the value from this List at a given index.

		Precondition: The list is not empty and index is valid
		(0 <= index < the list size).
		Postcondition: the element at position index has been
		removed (provided index is a legal position).
		*/

		void display( ostream &out ) const;
		/* Display the contents of this List

		Precondition: ostream out is open
		Postcondition: the items in this List have been output to stream out
		*/


		int find( ElementType value) const;
		/* Find the first occurrence of a value in this List

		Preconditions: None
		Postconditions: The return value is the index of the first List item
		that matches value. The first list item has index 0, the second has
		index 1, etc. The return value is -1 if value is not found in the list.
		*/


	private:

		NodePointer first;
		
		int mySize;

}; // end of List class

#endif