lispdoc - results for functionp

(functionp object)
Function: Return true if OBJECT is a FUNCTION, and NIL otherwise.
Example:
(defun tainted-p (value) (functionp value))
Mentioned in:
CLtL2 - 5.2. Functions
CLtL2 - 6.2.2. Specific Data Type Predicates
HyperSpec - Function FUNCTIONP
On Lisp - Recursion on Cdrs
On Lisp - Recursion on Subtrees