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Atom

Recognizer for atoms

(atom x) is true if and only if x is an atom, i.e., not a cons pair.

Atom has a guard of t, and is a Common Lisp function. See any Common Lisp documentation for more information.

Function: atom

(defun atom (x)
       (declare (xargs :guard t))
       (not (consp x)))

Subtopics

Atom-listp
Recognizer for a true list of atoms
Good-atom-listp
Recognizer for a true list of ``good'' atoms