Editing Reference (computer science) (section)

=== Lisp ===

One of the earliest opaque references was that of the [[Lisp (programming language)|Lisp]] language [[cons|cons cell]], which is simply a [[object composition|record]] containing two references to other Lisp objects, including possibly other cons cells. This simple structure is most commonly used to build singly [[linked list]]s, but can also be used to build simple [[binary tree]]s and so-called "dotted lists", which terminate not with a null reference but a value.