735: Mainline

You also need a function for adding an element to a list. In the simple implementation described here, all additions are made to the front of the list using the add member function. When you use add, you instantiate the following pattern:

A header variable 
  | 
  |   Name of the element-adding function 
  |    | 
  v    v  
train.add (pointer to a railroad_car object);