Elegantly refactoring code like this (to avoid a flag)

Question

I have a function running over an enumerable, but the function should be a little bit different for the first item, for example:

void start() { 
    List<string> a = ...
    a.ForEach(DoWork);
}

bool isFirst = true;

private void DoWork(string s) {
   // do something

   if(isFirst)
     isFirst = false;
   else
     print("first stuff");

   // do something
}

How would you refactor this to avoid that ugly flag?

Answer 1

Expounding on Jimmy Hoffa's answer if you actually want to do something with the first item you could do this.

DoFirstWork(a[0])

a.Skip(1).ForEach(DoWork)

If the point is that it is separate in logic from the rest of the list then you should use a separate function.