(atom)

(atoms-family)

(atom item)

Determine whether or not an item is an atom.

Generally, an atom is considered a number or a variable. More specifically, it is anything other than a list. The atom function tests item to see if it is an atom. If item is a list, a nil is returned. If it is not a list, a T is returned.

Examples

Code	Returns
(atom '(1 2 3))	nil
(atom 5)	T
(atom '5)	T

Tell me about...

(atoms-family format [symbol1 symbol2 ...])

Programming Overview of LISP (LISt Processing) Language