I am having problems overloading operator<< on my doublylinkedList program

[Bopaki]

The code is too long so I posted the sections that I have problems with:
Here is the error message that I get on the build log:
In file included from C:\Martin\MalikDownloads\Chapter 5 Source Code\myDoublyLinkedList\main.cpp:2:0:
C:\Martin\MalikDownloads\Chapter 5 Source Code\myDoublyLinkedList\doublyLinkedList.h:22:12: error: 'ostream' does not name a type
C:\Martin\MalikDownloads\Chapter 5 Source Code\myDoublyLinkedList\doublyLinkedList.h:155:1: error: 'ostream' does not name a type

here is the code:

 template <class Type>
class doublyLinkedList
{
    friend ostream& operator<<(ostream&,
                           const doublyLinkedList<Type>&);
       //Overload the stream insertion operator 

The above code is from the header file: doublyLinkedList

Here is the definition:

template<class Type>
ostream& operator<<(ostream& osObject,
					const doublyLinkedList<Type>& list)
{
    nodeType<Type> *current; //pointer to traverse the list

	current = list.first;  //set current to point to
	                       //the first node

	while(current != NULL)
	{
	   cout<<current->info<<"  ";  //output info
	   current = current->next;
	}//end while

	return osObject;
}

What frustrates me is that this code is exact as it is in the textbook (Data Structures using C++) written by DS Makil

[nuderobmonkey]

Have you forgotten to include <iostream> ? Or 'using namespace std;' ?

[Bopaki]

I got it to work eventually
Thank you all