forward_list::operator= in C++ STL

Forward list in STL implements singly linked list. Introduced from C++11, forward lists are useful than other containers for insertion, removal and moving operations (like sort) and allows time constant insertion and removal of elements.It differs from the list by the fact that forward list keeps track of the location of only next element while list keeps track to both next and previous elements.


This operator is used to assign new contents to the container by replacing the existing contents.
It also modifies the size according to the new contents.

Syntax :

forwardlistname1 = (forwardlistname2)
Parameters :
Another container of the same type.
Result :
Assign the contents of the container passed as the 
parameter to the container written on left side of the operator.


Input  :  myflist1 = 1, 2, 3
          myflist2 = 3, 2, 1, 4
          myflist1 = myflist2;
Output :  myflist1 = 3, 2, 1, 4

Input  :  myflist1 = 2, 6, 1, 5
          myflist2 = 3, 2
          myflist1 = myflist2;
Output :  myflist1 = 3, 2

Errors and Exceptions

1. If the containers are of different types, an error is thrown.
2. It has a basic no exception throw guarantee otherwise.





// CPP program to illustrate
// Implementation of = operator
#include <forward_list>
#include <iostream>
using namespace std;
int main()
    forward_list<int> myflist1{ 1, 2, 3 };
    forward_list<int> myflist2{ 3, 2, 1, 4 };
    myflist1 = myflist2;
    cout << "myflist1 = ";
    for (auto it = myflist1.begin(); it != myflist1.end(); ++it)
        cout << ' ' << *it;
    return 0;



myflist1 = 3 2 1 4

GeeksforGeeks has prepared a complete interview preparation course with premium videos, theory, practice problems, TA support and many more features. Please refer Placement 100 for details

My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using or mail your article to See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Article Tags :
Practice Tags :

Be the First to upvote.

Please write to us at to report any issue with the above content.