Question

I have a function that is to be called if a list has changed since it was last called, what would be the best way of implementing this?

ex:

List<A> OurList = new List<A>();
private void Update()
{
    Boolean Changed = //?    
    if(Changed) CheckList(OurList);
}

I would have assumed make a variable to store the old list and compare, but how would I update the old list to the new list without copying it all out? (If I do an assign, it will update the “old list” too)

Answer 1

The most efficient way would be to wrap the List<> in your own class and have all the mutating methods (Add, Remove) set a boolean flag.

Your Method can then just look at that flag and reset it.