Chapter 1, Toys

Laws

Car

The primitive car is defined only for non-empty lists.

Cdr

The primitive cdr is defined only for non-empty lists. The cdr of any non-empty list is always another list.

Cons

The primitive cons takes two arguments. The second argument to cons must be a list. The result is a list.

Null?

The primitive null? is defined only for list.

Eq?

The primitive eq? takes two arguments. Each must be non-numeric atom.