[Linux dev] Re: STL and pointers

["Izak Smit (ZA Cont)" <Izak.Smit@xxxxxxxxxxxxx>]

Hi Pieter.

Well the answer to your problem is:

1. YOU MUST LOOP THROUGHT THE STL VECTOR AND CALL THE delete on each pointer

Here's some code to show the result if you call call_back, and if you call
the delete on the vector.

ALWAYS remember.

The compiler will not see anything wrong if you call a delete on a NULL
POINTER!!!!! It's good practice :)...

Hope this helps.

#include <vector>
#include <iostream>

using namespace std;

vector<int *> myINT;
vector<int *>::iterator myINT_itr;

int main(int argc, char* argv[])
{
	int* i2;

	i2 = new int;
	*i2 = 100;

	cout << "ADDING NEW POINTER VALUE of 100 into vecotr" << endl;
	myINT.push_back( i2 );
	cout << "CALLING pop_back" << endl;
	myINT.back( );

	myINT.pop_back( );
	cout << "VALUE IN STL VECTOR: " << *myINT[0] << endl;

	cout << "Calling delete" << endl;
	delete myINT[0];
	
	cout << "VALUE AFTER DELETE: " << *myINT[0] << endl;

	return 0;
}





 -----Original Message-----
From: 	Pieter Louw [mailto:pieter@xxxxxxxxxx] 
Sent:	03 March 2003 01:31 PM
To:	dev@xxxxxxxxxxxx
Subject:	[Linux dev] STL and pointers

Hi there,

When you have a STL container with pointers, do you still need to delete the
pointers when you erase an item, or does the container handle the memory
management?

Example:

vector <Item*> items;

items->push_back(new Item());

//do stuff

items->pop_back();

/*does this delete the pointer, or do you have to delete it yourself like:
		delete items.back();
		items->pop_back();
*/

Thanks in advance

Pieter



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